New dental remains of Hispanopithecus laietanus (Primates: Hominidae) from Can Llobateres 1 and the taxonomy of Late Miocene hominoids from the Vallès-Penedès Basin (NE Iberian Peninsula)

Journal of Human Evolution 63 (2012) 231e246

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New dental remains of Hispanopithecus laietanus (Primates: Hominidae) from Can Llobateres 1 and the taxonomy of Late Miocene hominoids from the Vallès-Penedès Basin (NE Iberian Peninsula) David M. Alba a, *, Isaac Casanovas-Vilar a, Sergio Almécija a, b, Josep M. Robles a, c, Júlia Arias-Martorell d, Salvador Moyà-Solà e a

Institut Català de Paleontologia Miquel Crusafont, Universitat Autònoma de Barcelona, Edifici ICP, Campus de la UAB s/n, 08193 Cerdanyola del Vallès, Barcelona, Spain Department of Vertebrate Paleontology, American Museum of Natural History & NYCEP, 79 Street and Central Park West, New York, NY 10024, USA FOSSILIA Serveis Paleontològics i Geològics, S.L. Jaume I 87, 1er 5a, 08470 Sant Celoni, Barcelona, Spain d Unitat d’Antropologia, Departament de Biologia Animal, Universitat de Barcelona, Diagonal 645, 08028 Barcelona, Spain e ICREA at Institut Català de Paleontologia Miquel Crusafont & Unitat d’Antropologia Biològica (Dept. BABVE), Universitat Autònoma de Barcelona, Edifici ICP, Campus de la UAB s/n, 08193 Cerdanyola del Vallès, Barcelona, Spain b c

a r t i c l e i n f o

a b s t r a c t

Article history: Received 19 December 2011 Accepted 23 May 2012 Available online 25 June 2012

Here we report 12 teeth of the fossil great ape Hispanopithecus (Hominidae: Dryopithecinae: Hispanopithecini), recovered in 2011 from the locality of Can Llobateres 1 (MN9, early Vallesian, Late Miocene, ca. 9.7 Ma [millions of years ago]) in the Vallès-Penedès Basin (Catalonia, Spain). Besides an isolated dP3 from layer CLL1.1b in the eastern (classical) sector of the site, all of the remaining teeth come from facies CLL1.0 (roughly equivalent to CLL1.2 and CLL1.1b), located in the newly excavated western sector, and representing at least two different individuals. Based on facet congruence and degree of wear, all of the upper cheek teeth, a central incisor and a lateral incisor most likely correspond to a single young adult individual of unknown sex, whereas a very worn I2 and a female C1 represent one or two additional individual(s). Morphological and metrical comparisons allow us to attribute these remains to Hispanopithecus laietanus, which is the single hominoid species recognized at CLL1. The newly described teeth represent a significant addition to the hypodigm of this taxon, enabling us to more completely assess the degree of variation displayed by several teeth. In light of the new specimens, the previous tooth position assignment of several upper molars from Can Llobateres and Can Poncic is revised, and the criteria employed to distinguish Hispanopithecus crusafonti from H. laietanus are critically evaluated. On the basis of the available upper cheek teeth from these localities, a distinction at the species level between both samples is tentatively favored, mainly on the basis of P3, M1 and M2 proportions as well as I1 lingual morphology and proportions. The results of the 2011 field season unambiguously confirm that hominoidbearing fossiliferous layers from CLL1 are not exhausted. Additional excavations at this site are promising for the discovery of additional remains of H. laietanus in the near future. Ó 2012 Elsevier Ltd. All rights reserved.

Keywords: Dryopithecinae Hispanopithecini Early Vallesian Hispanopithecus crusafonti Fossil great apes

Introduction The last systematic excavation of the Late Miocene locality of Can Llobateres 1 (CLL1; Vallès-Penedès Basin, Catalonia, Spain; see reviews in Alba et al. (2011c, d) was carried out in 1981, leading to the recovery of nine dental specimens of the fossil great ape

* Corresponding author. E-mail addresses: [email protected] (D.M. Alba), [email protected] (I. Casanovas-Vilar), [email protected] (S. Almécija), [email protected] (J.M. Robles), [email protected] (J. Arias-Martorell), [email protected] (S. Moyà-Solà). 0047-2484/$ e see front matter Ó 2012 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.jhevol.2012.05.009

Hispanopithecus laietanus (Hominidae: Dryopithecinae: Hispanopithecini) (Begun et al., 1990; Golpe Posse, 1993). During the 1990s, excavations were carried out on the slightly younger levels of Can Llobateres 2 (CLL2), leading to the recovery of a partial face and skeleton of the same taxon (Moyà-Solà and Köhler, 1993, 1995, 1996). Excavations at CLL1 were not resumed until 2010 (Alba et al., 2011b,d; Marmi et al., 2012), by focusing on the removal of sterile sediments overlying the potentially hominoid-bearing levels with the aid of an excavator machine. These works provided additional surface to be manually excavated in the new western (W) sector of the site, as opposed to the classical, eastern (E) sector. Paleontological control of excavations by the diggers further led to the

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D.M. Alba et al. / Journal of Human Evolution 63 (2012) 231e246

recovery of plant remains, enabling a paleoenvironmental reconstruction for the site (Marmi et al., 2012), which is of greatest significance because it represents one of the latest occurrences of hominoids in mainland Western Europe (Casanovas-Vilar et al., 2011). Systematic manual excavations were recently carried out at CLL1 in 2011 (Alba et al., 2012), both in the E and in the W sectors, leading to the recovery of additional hominoid teeth (Alba et al., 2012 reported 11 teeth, but an upper central incisor was subsequently recovered during the preparation of the CLL1 specimens not catalogued as primate in the field). The aim of this paper is threefold: (1) to update the available information on the stratigraphy of the site, (2) report the newly recovered teeth, further updating the catalogue of available hominoid remains from CLL1, and (3) justify their taxonomic attribution to H. laietanus, by briefly comparing the new teeth with previously available remains from Can Llobateres and Can Poncic, and by further evaluating the taxonomic distinction of Hispanopithecus crusafonti in light of the newly reported teeth. Materials and methods The studied sample The new remains from CLL1 described in this paper (see Table 1) include an isolated dP3 (IPS58330) from CLL1.1b (spot 1), as well as 11 upper teeth including incisors, a canine and several cheek teeth (IPS58331 to IPS58340, and IPS61398) from CLL1.0 (spot 2; see next section for further details on the stratigraphic provenance). These teeth cannot be directly compared with the holotype of H. laietanus from La Tarumba 1, which includes only lower teeth (see Villalta Comella and Crusafont Pairó, 1944). The studied remains were thus compared with the previously known dental sample from CLL1 (Table 2) and CLL2, as well as other Vallès-Penedès localities (Begun et al., 1990; Harrison, 1991; Golpe Posse, 1993), which given the tooth positions described in this paper merely include the holotype and topotypes of H. crusafonti from Can Poncic (CP; Begun, 1992; see also Harrison, 1991; Golpe Posse, 1993). Both the newly recovered teeth and those included in the comparative sample are currently housed at the Institut Català de Paleontologia Miquel Crusafont (ICP).

Table 1 List of the dental remains of Hispanopithecus laietanus from CLL1 recovered during the 2011 field season. ICP no.

Provenancea

Brief description

Figures

IPS58330 IPS61398 IPS58331 IPS58332 IPS58333 IPS58334

CLL1.1b-P11 CLL1.0-L15 CLL1.0-M14* CLL1.0-K15* CLL1.0-M15* CLL1.0-L15

3A, 4A 3C, 4D 3B, 4L 3E, 5A 3D 3F, 5F

IPS58335 IPS58336 IPS58337 IPS58338 IPS58339 IPS58340

CLL1.0-K15 CLL1.0-L15* CLL1.0-L15 CLL1.0-L15 CLL1.0-M15 CLL1.0-L15*

Left dP3 crown Right I1 partial crown and root Left I2 crown Right C1 (\) crown and partial root Right I2 crown and root Left P3 buccal fragment of crown and roots Right P4 crown and partial roots Left P4 crown and partial roots Right M1 crown and partial roots Left M1 crown and partial roots Left M2 crown and partial roots Left M3 crown and partial roots

3H, 5M 3G, 5N 3J 3I, 7A 3K, 7A 3L, 7A

a See Fig. 1 for a stratigraphy of CLL1. The alphanumeric portion after the hyphen indicates the square of provenance within the planimetry (Fig. 2A) of spots 1 (in the case of IPS58330) and 2 (in the case of the remaining teeth; see also Fig. 2B). Asterisks indicate that these teeth were recovered during screen-washing instead of manual excavation. Abbreviations: CLL1, Can Llobateres 1; IPS, ‘Institut de Paleontologia de Sabadell’, acronym of the collections of the Institut Català de Paleontologia Miquel Crusafont (ICP), Universitat Autònoma de Barcelona, Spain.

Table 2 Updated catalogue of dentognathic specimens of Hispanopithecus laietanus from CLL1, including the specimens recovered during the 2011 field season (in bold type). ICP no.a

Old. no.a

Brief description

IPS1762 IPS1763 IPS1764 IPS1765 IPS1767 IPS1768 IPS1769 IPS1770 IPS1771 IPS1772 IPS1773 IPS1774 IPS1775 IPS1776 IPS1777 IPS1778 IPS1779 IPS1780 IPS1781 IPS1782 IPS1783 IPS1784 IPS1785 IPS1786 IPS1787 IPS1788 IPS1789 IPS1790 IPS1791 IPS1792 IPS1793 IPS1794 IPS1796 IPS1797

[IPS15]b [IPS15a]b [IPS7] [IPS41] [IPS18] [IPS19] [IPS20] [IPS12] [IPS13] [IPS14] [IPS16] [IPS17] [IPS21] [IPS22] [IPS23] [IPS24] [IPS25] [IPS48] [IPS37] [IPS38] [IPS39] [IPS42] [IPS43] [IPS44] [IPS45] [IPS46] [IPS53] [IPS54] [IPS55] [IPS56] [IPS69] [IPS10] [IPS6] [IPS9]

IPS1800 IPS1802 IPS1822 IPS1835 IPS1836 IPS1837 IPS1838 IPS1839 IPS1840 IPS1841 IPS1842 IPS1843 IPS1844 IPS1846 IPS7657 IPS9001 IPS34564 e IPS58330y IPS58331y IPS58332y IPS58333y IPS58334y IPS58335y IPS58336y IPS58337y IPS58338y IPS58339y IPS58340y IPS61398y

[IPS47] [IPS8] [IPS11] [IPS63] [IPS65] [IPS61] [IPS58] [IPS57] [IPS62] [IPS59] [IPS64] [IPS60] [IPS67] [IPS66] e [IPS70] e [IPS68] e e e e e e e e e e e e

Right P3 crown with partial roots Right M1 crown with partial roots Right mandibular fragment with C1eP4 (_) Right C1 (_) crown and partial rootc Left C1 (\) crown with partial root Left C1 (\) crown with root Left C1 (\) crown with root Right I1 crown with root Left M2? crown with partial rootsd Left M3 crown with partial rootse Left C1 (\) crown with rootf Right C1 (\) crown with rootg Left P4 crown with partial roots Right P4 crown with partial roots Left P3 crown with partial roots Right I1 crown with root Edentulous right mandibular fragment Right mandibular fragment with M2h Left M1 crown with partial rootsi Left M2 unerupted germj Right dC1 crown with root Right mandibular fragment with dP3 Left dC1 crown with root Left C1 (\) Right P4 unerupted germ Left M1 crown Left dC1 crown with partial rootk Right I2 crown with almost complete root Left P3 Right P3 crown with partial roots Edentulous right mandibular fragment Left M2 unerupted germl Left mandibular fragment with M1eM2 Right mandibular fragment with M2 and associated M1 Left M3 crown with partial rootsm Right mandibular fragment with M1eM3 Left M3 unerupted germ Left C1 (_) unerupted germn,o Right dC1 crown with rootn Left dC1 crown with partial rootn Left I2 crown with rootn,p Left dP3 crown with partial rootsn Right dC1 crown with rootn Right I1 crown with rootn Right dC1 crown with partial rootn,q Right I2 crown with rootn,r Right M1 unerupted germn,s Left dP4 crownn,t Left dC1 crown and partial rootu Left mandibular fragment with M1eM2v Right C1 (_) R crown fragmentw Right M1 unerupted germn,x Left dP3 crown Left I2 crown Right C1 (\) crown and partial root Right I2 crown and root Left P3 buccal fragment of crown and roots Right P4 crown and partial roots Left P4 crown and partial roots Right M1 crown and partial roots Left M1 crown and partial roots Left M2 crown and partial roots Left M3 crown and partial roots Right I1 partial crown and root

a ‘ICP no.’ refers to the current catalogue number of the specimen at the collections of the Institut Català de Paleontologia Miquel Crusafont, whereas ‘Old no.’ refers to those employed by Golpe Posse (1993), indicated in this paper within brackets. Harrison (1991) first published their equivalences, but as explained in some of the following notes, with some minor mistakes that are emended here. b Contrary to Harrison’s (1991) assertion, IPS1762 corresponds to [IPS15] and IPS1763 to [IPS15a], instead of the reverse.

D.M. Alba et al. / Journal of Human Evolution 63 (2012) 231e246 c This upper male canine, formerly termed [IPS41], and previously attributed to ‘Dryopithecus’ or Sivapithecus indicus (e.g., Crusafont-Pairó and Golpe-Posse, 1973; Golpe Posse, 1993), was labeled as IPS1801 for more than a decade, so that Ribot et al. (1996) and Pickford (2012) referred to it as IPS1801, and Alba et al. (2001) referred to it as CLL1801. Harrison (1991) did not provide a modern number for this specimen, but asserted that IPS1801 corresponded to a ‘deciduous incisor of a ruminant’, [IPS40], to which another new number, IPS34536, was given a few years ago. Golpe Posse (1993) not only asserted that this incisor was non-primate, but further explained that the old number [IPS40] was subsequently applied to another specimen, which Golpe Posse (1993) considered to be a P4. In the same page, Golpe Posse (1993) asserted this specimen to be either a right P4 from Can Llobateres or a left P4 from Can Poncic, although apparently the former locality was the correct one (see Golpe Posse, 1993). Harrison (1991) attributed to this premolar the numbers IPS1795 [IPS40] and further concluded that it was possibly a premolar germ of a suid. This was implicitly recognized by Ribot et al. (1996), who did not comment on this particular specimen. Like in the preceding case, this specimen was given yet another number, IPS34562. Both IPS1801 (¼IPS34536) [IPS40] and IPS1795 (¼IPS34562) are here considered non-primate, and hence excluded from this catalogue. The reasons why [IPS41] was subsequently designated as IPS1801 are obscure and might stem from the same objectionable practice that old numbers were reassigned when their primate affinities were disproved. The fact is that, according to the ICP records, the canine [IPS41] would correspond in fact to IPS1765 (Alba and Moyà-Solà, 2012). d Begun et al. (1990) and Golpe Posse (1993) identified this tooth as an M3, but as noted by Harrison (1991), this is contrary to the presence of a distal contact facet. Consequently, the latter author identified this specimen as an M2, which is the attribution tentatively followed here, although it is at odds with its short mesiodistal length (resulting in a high breadth/length index). Alternatively, this tooth might be attributed to an M1 (which is however counter-indicated by the tapering of the distal lobe), or to an M3 with a distal contact facet due to the presence of a supernumerary molar (see main text for further discussion). e Incorrectly attributed to the number IPS1778 by Harrison (1991). f Harrison (1991) attributed the left C1 (\) [IPS16] to IPS1765, but according to the label and ICP records the correct number for this specimen is IPS1773, whereas IPS1765 corresponds to the C1 of ‘Dryopithecus cf. indicus’ that in the old nomenclature was termed [IPS41]. g Harrison (1991, his Table 1) incorrectly attributed [IPS17] to IPS1766 instead of IPS1774, but IPS1766 does in fact correspond to the C1 (\) [IPS49] from Can Mata I (Crusafont-Pairó and Golpe-Posse, 1973), as stated by Harrison himself (1991, his Table 3). h Although both Begun et al. (1990) and (tentatively) Harrison (1991) identified this tooth to an M1, we concur with Golpe Posse (1993) that it corresponds to an M2. i Although Golpe Posse (1993) identified this tooth to an M2, we concur with Begun et al. (1990), Harrison (1991) and Kelley et al. (2001) that it corresponds to an M1. This tooth was sectioned for paleohistological study (see Kelley et al., 2001). j Although Golpe Posse (1993) identified this tooth to an M3, we concur with Harrison (1991), Ribot et al. (1996) and Kelley et al. (2001) that it corresponds to an M2. This tooth was sectioned for paleohistological study (see Kelley et al., 2001). k Crusafont Pairó and Golpe Posse (1993) incorrectly applied [IPS53] to an upper molar germ from Can Poncic (currently, IPS1814), previously referred as [IPS47] by Golpe Posse (1993) and also as [IPS74] by Harrison (1991); see further comments below. l Although Harrison (1991) identified this tooth to an M1, we concur with Begun et al. (1990), Golpe Posse (1993), Ribot et al. (1996) and Kelley et al. (2001) that it corresponds to an M2, given the marked distal tapering. This tooth was sectioned for paleohistological study (see Kelley et al., 2001). m This specimen was listed as [IPS47] by Begun et al. (1990) and as IPS1800 [IPS47] by Harrison (1991). However, according to Golpe Posse (1993), this M3 initially labeled as [IPS47] was not primate. As a result, an upper molar germ from Can Poncic, previously referred to as [IPS53] by Crusafont-Pairó and Golpe-Posse (1973) and [IPS74] by Golpe Posse (1982), was transferred to [IPS47]. Harrison (1991) still referred to the Can Poncic specimen as IPS1814 [IPS74], and identified it as an M3 germ, although we consider it more likely to be an M1. In any case, given that we consider IPS1800 to be primate, the result is that the old number [IPS47] currently applies to both this specimen from CLL1 and IPS1814 from Can Poncic. n Excavated in 1981 according to Golpe Posse (1993). This author reported up to 12 teeth of H. laietanus recovered that season, whereas Begun et al. (1990) only reported nine. This is because the latter authors considered IPS1843 [IPS60] and IPS1846 [IPS66] to be non-primate (although we disagree from their view, see further notes below), and also because they did not take into consideration [IPS68], which was most likely under loan by that date (see also a note in this regard below). o Incorrectly attributed to the right side by Golpe Posse (1993; see Begun et al., 1990; Harrison, 1991). p Although this specimen was identified as a right I2 by Begun et al. (1990), as a left dI1 by Golpe Posse (1993), and as a right I1 by Harrison (1991), in our opinion it corresponds to a left I2. q Begun et al. (1990) incorrectly attributed this specimen to the left side (see Harrison, 1991; Golpe Posse, 1993).

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r Even though Begun et al. (1990) considered this tooth to be ‘non-primate’, and Harrison (1991) considered it to be an ‘incisor of uncertain affinities’, in fact it has considerable resemblances to the I2 IPS1790 [IPS54] of H. laietanus, as well as to the newly recovered specimen IPS58331, so that we concur with Golpe Posse (1993) that this specimen is an incisor of Hispanopithecus. The latter author identified it as a dI2, but in our opinion it corresponds instead of a permanent I2 (see text for further discussion). s Although Golpe Posse (1993) identified this specimen as an M2, and Begun et al. (1990) as either an M1 or an M2, we concur with Harrison (1991) that it corresponds to an M1. t Although Begun et al. (1990) did not consider this tooth to be primate, we concur with Harrison (1991) and Golpe Posse (1993) in asserting its primate affinities. u Unpublished specimen found by S. Moyà-Solà ca. 1989e1990. v Begun et al. (1990) did not list this specimen, and Harrison (1991) did not provide an updated number for it, although it was mentioned by Ribot et al. (1996). w Found years ago by M. Pickford among the ICP classical collections from CLL1. x Although Golpe Posse (1993) tentatively identified this tooth to an M2, both Harrison (1991) and Andrews and Martin (1991) asserted that it corresponds to an M1. This tooth, which is not currently housed at the ICP, was sectioned for paleohistological study (Andrews and Martin, 1991). It was not listed by Begun et al. (1990), and Harrison (1991) did not provide any updated number for this specimen, although he thanked “Lawrence Martin for providing details of this specimen”. This suggests that this tooth had been already sent to him on loan before the early 1990s, so that neither Begun et al. (1990) nor Harrison (1991) had the opportunity to study this specimen, which had been nevertheless previously studied by Golpe Posse (whose study appeared in 1993). y Recovered during the 2011 season.

The fossil comparative sample Only brief descriptions of the occlusal morphology of the 12 newly recovered teeth (Table 1) are provided below, since the dental morphology of H. laietanus from CLL1 is already known on the basis of 52 previously available dentognathic specimens, which include isolated teeth and a few mandibular fragments (Begun et al., 1990; Harrison, 1991; Golpe Posse, 1993). Comparisons are restricted to homologous hominoid dental specimens from the Vallès-Penedès Basin, attributed to either H. laietanus or H. crusafonti, with particular emphasis on those features previously proposed to be diagnostic among these taxa (Begun, 1992, 2002). It should be taken into account that the introduction of ‘modern’ IPS collection numbers for the Vallès-Penedès hominoid sample during the early 1990s caused some confusion in the literature, the new numbers being employed by Harrison (1991), Begun (1992), Ribot et al. (1996) and most subsequent authors, but not yet by Begun et al. (1990) or Golpe Posse (1993). In Table 2, an annotated catalogue is provided, which updates the information provided by Harrison (1991), including some emendations in collection numbers as well as in tooth position identification (see also later). Measurements and statistical comparisons Measurements of mesiodistal crown length (MD, in mm) and buccolingual crown breadth (BL, in mm) were employed to compare the described material with other available samples of Hispanopithecus spp. from the Vallès-Penedès Basin. In the case of molars, BL measurements were taken separatedly at the mesial and distal lobes, although metrical comparisons were based on maximum buccolingual breadth. In particular, the breadth/length index (BLI, in %), computed as BL (maximum)/MD
100, was employed to reflect the proportions of the upper cheek teeth. Similarly, the occlusal area (A, in mm2) of the upper cheek teeth was approximated as MD
BL. The size discrepancy between the M2 and the M1 was computed as the ratio between their respective MD and A, the resulting ratios being labeled as M2M1MD and M2M1A. Comparability of dental measurements taken by different authors, due to subtle differences in measuring techniques, might be a problem, resulting in higher interobserver than intraobserver error (Mahler, 1973). In order to minimize this problem, instead of

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relying on published measurements for previously known Hispanopithecus teeth, all of the measurements employed in this paper were taken by the senior author (DMA). Measurements were taken to the nearest 0.1 mm on the original specimens. The descriptive statistics for the above-mentioned variables are reported for the upper cheek teeth of H. laietanus (CLL1 and CLL2 samples together), as well as H. crusafonti (CP sample). Additionally, bivariate dental plots of BL vs. MD were employed to visually assess the size and proportions of the upper cheek teeth from these three localities separately. Significant differences for the means of the several measured variables between H. laietanus and H. crusafonti were further tested by means of analysis of variance (ANOVA) using the SPSS v. 16.0 statistical package for Mac. In the case of P3 and M1 proportions, in order to further assess the significance of the differences in BLI between H. laietanus and H. crusafonti, we relied on the corrected coefficient of variation (CV, in %) of extant hominoid species (Hylobates hoolock and Pan troglodytes), computed as CV ¼ (SD/mean)
[1 þ (1/4N)]
100 (Sokal and Rohlf, 1995), where SD is the standard deviation of the sample and N is the sample size. The H. hoolock sample included 33 males, 27 females and an unsexed individual for the P3 (N ¼ 61), and 37 males, 23 females and two unsexed individuals for the M1 (N ¼ 62). In turn, the P. troglodytes sample (three subspecies) included 26 males, 16 females and six unsexed specimens for the P3 (N ¼ 48), and 25 males, 21 females and 12 unsexed specimens for the M1 (N ¼ 58). Measurements for extant taxa were taken by the senior author of this paper (DMA) at the American Museum of Natural History (AMNH) in New York (USA). In the case of the P3, a randomization approach was further applied to two extant samples, to randomly generate 100 replicates (each without resampling) with the same sample size as the Hispanopithecus spp. sample (N ¼ 7). Each extant set of replicates was then employed to compute the probability of obtaining a greater CV than that computed for the P3 of the combined Hispanopithecus sample. The null hypothesis that the fossil sample does not exceed the variation seen within an extant species was rejected only when the probability of finding a higher CV than that of Hispanopithecus among the extant replicates was lower than 5%, following the standard statistical criterion of p < 0.05. Geological background and taphonomy Geology and age Two different localities must be distinguished within the site of Can Llobateres: CLL1, which shows a greater paleodiversity and has yielded most of the dentognathic hominoid remains (Begun et al., 1990; Golpe Posse, 1993; this study), and the slightly younger Can Llobateres 2 (CLL2), which shows a much lower paleodiversity but which in the 1990s yielded a partial skeleton of H. laietanus (MoyàSolà and Köhler, 1993, 1995, 1996). The whole site comprises a 20 m-thick local stratigraphic section that corresponds to a distalinterchannel alluvial plain (Agustí et al., 1996; Alba et al., 2011c,d). The lithological and sedimentological features of the several layers of CLL1, situated in the lower part of the series, are indicative of sedimentation in a poorly drained area, with development of ponds and shallow small lakes (Begun et al., 1990; Agustí et al., 1996; Alba et al., 2011c,d), in agreement with the paleobotanical evidence (Marmi et al., 2012). Biostratigraphically, the section of Can Llobateres records the early/late Vallesian transition (Agustí et al., 1996, 1997), i.e., the Middle/Late Miocene boundary, with estimated ages of 9.72 Ma (millions of years ago) (MN9) for CLL1 and 9.64 Ma (MN10) for CLL2, on the basis of litho-, bio- and magnetostratigraphic data (Agustí et al., 1996, 1997; Casanovas-Vilar et al., 2011; Alba et al., 2011c,d).

Stratigraphy Although Marmi et al. (2012) provide an updated stratigraphy of CLL1, further refinements are possible after the 2011 field season (see Fig. 1). Two different sectors were defined on the basis of a subvertical normal fault with a small leap that affects the whole Can Llobateres section (Fig. 1B). The classical outcrops of CLL1 correspond to the footwall block, situated in the E sector, whereas the new area prepared for excavation in 2010 with the aid of heavy machinery corresponds to the hanging-wall, situated in the W sector. The excavation of a drainage ditch with heavy machinery in 2011 further revealed two different levels below the classical section of CLL1 (Fig. 1A). From bottom to top, CLL1.R is a 1 m-thick layer of reddish brown silts with abundant grayish green and white decolorations, interbedded sands, and eventually macrovertebrate remains, and CLL1.G is a conglomerate layer about 25 cm-thick that shows an erosive surface relative to CLL1.R. The latter is overlain by layer CLL1.H, a brown layer with silts and sands, about 35 cm-thick, which shows a transitional contact with CLL1.1a (equivalent to layer ‘a’ of Villalta Comella and Crusafont Pairó, 1943: Fig. 1). The more reddish coloration of CLL1.R is indicative of more aerial, oxidizing conditions than in the remaining (classical) levels of CLL1 (see Marmi et al., 2012, for a paleoenvironmental reconstruction based on plant remains from CLL1.4p and CLL1.2), suggesting that the former layer constitutes the top of a preceding depositional cycle characterized by different (less humid) environmental and/or depositional conditions. During 2010 and 2011, three different spots were excavated (Fig. 2A): spots 1 and 3 in the E sector, and spot 2 in the W sector. Begun et al. (1990) had reported the find of hominoid teeth from CLL1.2, as well as from the upper part of CLL1.1b (transitional with the former) in the E sector. In agreement with that, in 2011 a hominoid tooth was found in the middle part of CLL1.1b, in spot 1 of the E sector. However, most of the new hominoid remains reported in this paper come from CLL1.0, in spot 2 of the W sector. According to the situation of the fault trace in the W sector next to spot 2, after the 2011 field season CLL1.0 can be unambiguously located in the hanging-wall. This conclusively shows that this ‘layer’ is a distinct facies of levels CLL1.1b (equivalent to the upper part of layer ‘1’ of Begun et al., 1990, and to layer ‘c’ of Villalta Comella and Crusafont Pairó, 1943) and CLL1.2 (equivalent to layer ‘2’ of Begun et al., 1990, and probably to layer ‘d’ of Villalta Comella and Crusafont Pairó, 1943), in further agreement with the hominoidbearing levels previously reported by Begun et al. (1990). In spot 2, the color transition between CLL1.1b and CLL1.2 is irregular and situated stratigraphically lower than in the E sector and other parts of the W sector, thus resulting in a layer of light brown clays with versicolor decolorations, abundant microvertebrate remains, some macrovertebrate remains, abundant fig fruits and poorly preserved mollusk shells that is called facies CLL1.0. Towards the bottom, CLL1.0 becomes darker and the mollusks shells are better preserved, thus becoming more similar in appearance to CLL1.b. Eleven out of the 12 hominoid remains reported here were found in the middle part of facies CLL1.0, which is roughly equivalent to CLL1.2 and the uppermost part of CLL1.1b. The sediments excavated in 2010 and 2011 in spot 3, mainly corresponding to the channel deposits CLL1.4a, yielded abundant macrovertebrate remains but no hominoid teeth. Preservation and taphonomic remarks The 11 dental remains (IPS58331 to IPS58340, and IPS61398) from the W sector were found scattered over a surface of 4 m2 of CLL1.0 (Fig. 2B; Table 1), six of them during manual excavation, and the remaining ones during screen-washing of the excavated

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Figure 1. A. Updated correlation of the stratigraphic columns of CLL1, showing the provenance of the hominoid teeth described in this paper. B. Photograph of CLL1 in 2010, showing superimposed the several outcropping levels, the location of the excavated spots, and the approximate placement of the columns depicted in (A) (updated from Marmi et al., 2012).

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Except for the damaged, partial P3 IPS58334 and the slightly broken I1 IPS61398, the crowns are intact, and in all instances the enamel is well preserved (showing perikymata and enamel hypoplasias). In contrast, the roots of all specimens are partially broken. In some instances, root damage is attributable to the screenwashing process, although manually excavated specimens show that the roots were already partially broken prior to fossilization. This suggests that the maxillary bone was completely dissolved before burial. In turn, the relatively small distance between the remains from the best represented individual indicates that only minor transport (probably under water) took place prior to burial, probably causing the partial breakage of the roots. Besides the hominoid teeth, remains from CLL1.0 include abundant terrestrial gastropod shells, silicified fig fruits, and small mammal dental and postcranial remains, as well as some dentognathic and postcranial remains of large mammals (albeit fragmentary, being preserved as relatively small, usually centimetric, remains). Most of the macromammal fossils from CLL1.0 consist of scattered dentognathic remains of a cervid, presumably from a single individual, suggesting the intervention of similar taphonomic processes to the case of the hominoid teeth. Systematic paleontology

Figure 2. A. Photograph of CLL1, showing the situation of the excavated spots, as well as the in situ trace of the fault relative to spot 2 (further showing the limits between the E and W sectors). B. Spatial distribution of H. laietanus dental remains in facies CLL1.0 of spot 2 (W sector); crosses indicate the exact provenance of the remains that were manually excavated, whereas catalogue numbers within parentheses indicate that these remains were recovered during screen-washing, so that their provenance within the denoted square is unknown.

Order Primates Linnaeus, 1758 Infraorder Catarrhini É. Geoffroy Saint-Hilaire, 1812 Superfamily Hominoidea Gray, 1825 Family Hominidae Gray, 1825 Subfamily Dryopithecinae Gregory and Hellman, 1939 Tribe Hispanopithecini Cameron, 1997 Genus Hispanopithecus Villalta Comella and Crusafont Pairó, 1944 Subgenus Hispanopithecus Villalta Comella and Crusafont Pairó, 1944 Hispanopithecus (Hispanopithecus) laietanus Villalta Comella and Crusafont Pairó, 1944 (Figs. 3AeL, 4A, D, L, 5A, F, M, N and 6A) Studied material See Table 1. This material is housed at the Institut Català de Paleontologia Miquel Crusafont (ICP; Barcelona, Spain). Measurements (Table 3). Description and comparisons

sediments. Although no dental position is repeated, both the left I2 IPS58331 and the right female C1 IPS58332 (separated more than 2 m from each other) show an advanced degree of wear, suggesting that they do not belong to the same individual as the slightly worn right I2 IPS58333. On the contrary, the wear degree of the latter tooth is compatible with that shown by the remaining teeth, the I1 being moderately worn, the premolars being only slightly worn, the two (right and left) M1 showing a moderate degree of wear (with some dentine exposure at the apices of the hypocone, the metacone and especially the protocone), the M2 showing a slight degree of wear, and the M3 being almost unworn. This is compatible with IPS58333 to IPS58340 and IPS61398 (all of which were found quite close to one another; Fig. 2B) belonging to a single, young adult individual of unknown sex, with at least another individual being represented by the remaining two teeth from the same level. Such assumption if further reinforced by compatibility between the respective contact facets of adjacent upper cheek teeth amongst the sample, although given that they were not found in close spatial association, different catalogue numbers have been given to the specimens. A third individual is represented by the dP3 IPS58330 recovered from the E sector.

Deciduous upper third premolar As far as it can be ascertained, IPS58330 (Figs. 3A and 4A) shows a similar morphology to the much less worn specimen IPS1839 from CLL1 described by Begun Table 3 Dental measurements (mm) of the teeth of Hispanopithecus laietanus from CLL1 recovered during the 2011 field season.

IPS58330 IPS61398 IPS58331 IPS58332 IPS58333 IPS58334 IPS58335 IPS58336 IPS58337 IPS58338 IPS58339 IPS58340

Tooth

MD

BLm

dP3 I1 I2 C1 (\) I2 P3 P4 P4 M1 M1 M2 M3

6.3 (7.4) 4.8 (6.7) 4.9 >7.6 7 6.9 9.7 9.6 10.8 8.9

6.6 7.5 (5.6) 5.4 6.0 e 10.4 10.5 10.6 10.7 11.6 11.9

BLd

10.1 10.1 10.0

BLI 104.8 (101.4) 116.7 80.6 122.5 e 148.6 152.2 109.3 111.5 107.4 133.7

Abbreviations: MD, mesiodistal length; BL, buccolingual breadth; m, mesial lobe (for molars) or maximum for other teeth; d, distal lobe; BLI, breadth/length index, computed as BL (maximum)/MD
100.

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et al. (1990; see Fig. 4B): subquadrangular occlusal outline much longer on the buccal side of the crown; short, wide and obliquely-oriented mesial fovea, separated from the deeper trigon basin by a transverse hypoparacrista that runs towards the apex of the protocone; sinuous and shallow groove that runs in a mesiodistal direction along the bottom of the trigon basin; and relatively large and protruding paracone. These two specimens do however differ in some respects, thus showing some degree of intraspecific variability regarding the morphology of this tooth. In

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particular, IPS58330 displays a distinct and well-individualized (albeit small) metacone with a short (almost non-existent) premetacrista but with a long postmetacrista comparable in length with the postparacrista. In contrast, the latter cusp is limited to a small enamel swelling situated close to the end of the postparacrista in IPS1839. Moreover, the new specimen displays a fine but distinct transverse hypometacrista that originates from the apex of the metacone and runs towards the center of the crown (ending at the above-mentioned sinuous

Figure 3. Teeth of Hispanopithecus laietanus from CLL1 recovered during the 2011 field season. A. Left dP3 (IPS58330), in occlusal, buccal and mesial views; B. Left I2 (IPS58331), in occlusal, mesial and lingual views; C. Right I1 (IPS61398), in occlusal, labial, mesial, lingual and distal views; D. Right I2 (IPS58333), in occlusal, labial, mesial, lingual and distal views; E. Right female C1 (IPS58332), in occlusal, buccal, mesial, lingual and distal views; F. Left P3 (IPS58334), in occlusal, buccal and mesial views; G. Left P4 (IPS58336), in occlusal, buccal and mesial views; H. Right P4 (IPS58335), in occlusal, buccal and mesial views; I. Left M1 (IPS58338), in occlusal, buccal and mesial views; J. Right M1 (IPS58337), in occlusal, buccal and mesial views; K. Left M2 (IPS58339), in occlusal, buccal and mesial views; L. Right M3 (IPS58340), in occlusal, buccal and mesial views.

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Figure 4. Upper deciduous premolars and permanent incisors of Hispanopithecus laietanus from CLL1 recovered during the 2011 field season, compared with other homologous specimens of H. laietanus from CLL1 and CLL2, as well as H. crusafonti from Can Poncic (CP). AeC. Crown of the left dP3 IPS58330 from CLL1 (A), compared with IPS1839 from CLL1 (B) and IPS34535 from CLL2 (C), in occlusal view; DeK. Crown of the right I1 PS61398 from CLL1 (D), compared with IPS1770 from CLL1 (E), IPS1778 from CLL1 (F), IPS18000.9 (reversed) from CLL2 (G), IPS18000.10 from CLL2 (H), IPS1807 from CP (I), IPS1808 (reversed) from CP (J) and IPS1809 (reversed) from CP (K), in occlusal and lingual views; LeO. Crown of the right I2 IPS58333 from CLL1 (L), compared with IPS1790 from CLL1 (M), IPS1843 from CLL1 (N) and IPS18000.11 (reversed) from CLL2 (O), in occlusal and lingual views.

groove of mesiodistal direction, without forming a continuous crista obliqua), whereas in IPS1839 this crest is completely absent. Finally, IPS58330 differs from IPS1839 by displaying a faint and rudimentary cingulum along the whole buccal wall of the crown, whereas in IPS1839 the vestiges of buccal cingulum are restricted to the mesiobuccal aspect of the paracone. The somewhat damaged and previously unpublished dP3 IPS34535 from CLL2 (Fig. 4C) shows an intermediate morphology between the two above-mentioned specimens, showing like IPS58330 a distinct metacone and a better developed (albeit very narrow) buccal cingulum, but lacking a hypometacrista just like IPS1839. Upper central incisor The new I1 IPS61398 (Figs. 3C and 4D) preserves the basal-most portion of the root and most of the crown (except for an apical mesial fragment that is broken away). The crown shows a very conspicuous enamel hypoplasia situated at about one-third of the crown height. This specimen shows similar occlusal dimensions to previously known Vallès-Penedès

Hispanopithecus specimens (Fig. 6A), but both in crown height and lingual features it most closely resembles the H. laietanus central incisors from CLL1 (Harrison, 1991; Begun, 1992; Golpe Posse, 1993; Ribot et al., 1996; Fig. 4E and F) and CLL2 (Moyà-Solà and Köhler, 1995; Ribot et al., 1996; Fig. 4G and H). Thus, the new specimen confirms that, as noted by previous authors (Begun, 1992; Andrews et al., 1996), the H. laietanus I1 sample differs from that of H. crusafonti by displaying a more brachyodont crown and by lacking the characteristic lingual traits displayed by the latter, which include a protruding, narrow but very conspicuous median lingual pillar, flanked by very marked clefts, as well as a thick, pillar-like mesial ridge. The new specimen from CLL1 shares with previously known H. laietanus I1 the presence of a shelf-like basal bulge that is continuous with the moderately-developed mesial and distal ridges. However, IPS61398 uniquely displays a faint and not very protruding triangular lingual pillar that is apically prolonged until about two-thirds of crown height, and which

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Figure 5. Upper canines and premolars of Hispanopithecus laietanus from CLL1 recovered during the 2011 field season, compared with other homologous specimens of H. laietanus from CLL1 and CLL2 as well as H. crusafonti from Can Poncic (CP). AeE. Crown of the right female C1 IPS58332 (A), compared with IPS1769 (reversed) from CLL1 (B), IPS1774 from CLL1 (C), IPS1773 (reversed) from CLL1 (D) and IPS1786 (reversed) from CLL1 (E), in buccal and occlusal views; FeL. Left P3 crown IPS58334 (buccal fragment) from CLL1 (F), compared with IPS1792 (reversed) from CLL1 (G), IPS18000.5 (reversed) from CLL2 (H), IPS1806 from CP (I), IPS1810 (reversed) from CP (J), IPS1798 (holotype) from CP (K) and IPS1817 from CP (L), in occlusal view; MeQ. Right (IPS58335, reversed) and left (IPS58336) P4 crowns from CLL1 (M and N, respectively), compared with IPS1787 (germ, reversed) from CLL1 (O), IPS18800.5 (reversed) from CLL2 (P) and IPS1798 (holotype) from CP (Q), in occlusal view.

partially separates the mesial from the distal fovea, instead of displaying multiple vertical enamel folds and crenulations like the previously known specimens attributed to H. laietanus. In this sense, the new I1 from CLL1 shows a higher degree of variation of incisor lingual traits for H. laietanus than the previously available sample, although at the same time it reinforces the view (Begun, 1992) that this taxon differs from H. crusafonti with regard to I1 lingual morphology and crown height. Upper lateral incisor Among the two available new I2, crown morphology can be best evaluated on the basis of the slightly worn specimen IPS58333 (Figs. 3D and 4L), which resembles in several respects the similarly worn I2 IPS1790 from CLL1 (Harrison, 1991; Golpe Posse, 1993; Fig. 4M) as well as the much more worn I2 IPS18800.11 from CLL2 (Moyà-Solà and Köhler, 1995; Fig. 4O). Similarities include the relatively high and asymmetric crown profile, which is somewhat tilted mesially and attains maximum

length at about crown midheight. In all of these three specimens, there is a lingual bulge mainly situated on the mesial portion of the crown, a distal fovea that displays some enamel crenulations and that is more extensive than the mesial one, and moderatelydeveloped mesial and distal marginal ridges. Around the bulge, there is a faint lingual cingulum that separates it from the remaining lingual portion of the crown. This bulge is less swollen in the new (Fig. 4L) than in the previously known specimens (Fig. 4M and O), although in the former it is apically continued by a short and fine crest. In none of the specimens can the bulge be considered to constitute a distinct lingual pillar. IPS58333 further differs from IPS1790 by displaying a less robust and more clearly peg-shaped crown, although in both specimens the crown is narrower apically than at about midheight. Another upper lateral incisor from CLL1, IPS1843 (Fig. 4N), which only shows a very minimal degree of wear, closely resembles the peg-shaped

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Figure 6. Dental proportions of buccolingual width (BL) versus mesiodistal length (MD) for the incisors (A), premolars (B) and molars (C) of Hispanopithecus laietanus from CLL1 recovered during the 2011 field season, compared with previously available remains of the same taxon from CLL1 and CLL2, as well as remains of Hispanopithecus crusafonti from CP. Black arrows indicate the new teeth reported in this paper.

morphology of IPS58333 (Fig. 4L), although the former differs from all the available specimens by displaying a slightly smaller and more slender crown, which further lacks any trace of lingual bulge. On the contrary, this specimen displays a uniformly concave lingual surface with some rugosities of the enamel, but where no mesial and distal fovea can be distinguished. IPS1843 was considered to be a dI2 by Golpe Posse (1993), whereas Begun et al. (1990) concluded it was ‘non-primate’ and Harrison (1991) considered it to be an ‘incisor of uncertain affinities’. Close similarities with other available specimens, and in particular the newly recovered IPS58333, argue in favor of its primate affinities. In turn, the well-developed root, similar to that of the other

specimens, coupled with the minimal degree of wear, suggest that it is not a deciduous specimen, but a permanent one. Differences in size compared with the other specimens parallel differences that can be found in other teeth of Hispanopithecus (see latter), being probably attributable to a small female specimen. If our interpretation is correct, this specimen, coupled with IPS58333, shows a previously unsuspected degree of intraspecific variation in the development of lingual structures and crown shape for this particular tooth in H. laietanus. Upper female canine Occlusal morphology cannot be evaluated in the female C1 IPS58332 (Figs. 3E and 5A) due to the marked degree of wear, which is more advanced than in other homologous specimens from the same locality (Fig. 5BeE). These specimens show that wear is in all instances higher on the distal than on the mesial portion of the crown, although not even IPS1786 shows such an advanced degree of wear as IPS58332, in which almost the entire distal portion of the crown and even a distal part of the root have been worn away. Upper premolars The morphology of the P3 also cannot be adequately ascertained, not because of wear (which is moderate, showing some dentine exposure at the protocone apex), but due to the fragmentary nature of IPS58334 (Figs. 3F and 5F). The preserved buccal portion of this tooth is however comparable with specimens attributed to either H. laietanus from CLL1 (Fig. 5G) and CLL2 (Fig. 5H) or H. crusafonti from CP (Fig. 5IeL), all of which show marked preparacrista and postparacrista of similar length, as well as a short mesial fovea. Like some of the previously known specimens of both species, in IPS58334 the mesial fovea is partially disrupted by a short and longitudinal, secondary crest. The presence of enamel wrinkling on the distal fovea (variable in H. crusafonti) cannot be evaluated in IPS58334. The morphology of the P4 can be more completely evaluated on the basis of the two slightly worn specimens IPS58335 and IPS58336 (Figs. 3G, H and 5M, N). As far as it can be ascertained depending on the wear of the previously available specimens, the two new P4 from CLL1 resemble those of both H. laietanus (Fig. 5O and P) and H. crusafonti (Fig. 5Q). Similarities include, among others, their oval occlusal outline (longer on the lingual than on the buccal side), the presence of a tubercle-like thickening of the enamel at the end of the postparacrista, and the presence of a thin groove of mesiodistal direction at the bottom of the trigon basin. In all of the available specimens from CLL1 (Fig. 5MeO) and apparently also in the more worn specimens from CLL2 (Fig. 5P), the hypoparacrista, which originates from the paracone apex, is not transversely but obliquely-oriented, thus running towards the mesial marginal ridge instead of to the protocone tip. Although a secure assessment is precluded in the holotype and only available specimen of H. crusafonti (Fig. 5Q) due to wear, it seems that in the latter taxon the hypoparacrista originates from the preparacrista and displays a more transverse orientation towards the protocone apex. The two new specimens further differ from the unerupted germ IPS1787 from CLL1 (Fig. 5Q) in that the curved hypoparacrista merges with the mesial marginal ridge, thus resulting in a narrower mesial fovea that is more clearly restricted to the buccal portion of the crown. In IPS1787, in contrast, the hypoparacrista twists distally before reaching the mesial marginal ridge, so that the mesial fovea is not completely isolated from the trigon basin. It is also noteworthy that in the new specimen from the right side (Fig. 5M), the hypoparacrista is double, being constituted by a thick and straight distal crista as well as a more sinuous and fine mesial crista, which merge before reaching the mesial marginal ridge. At least regarding the Can Llobateres sample, the minor differences reported above are merely attributable to intraspecific variation, whereas the significance of the hypoparacrista orientation seems difficult to evaluate on the basis of the single available CP specimen.

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The breadth/length index of the newly reported P4 (Fig. 6B) is higher than the previously known specimen from CLL1, but quite similar to IPS18000 from CLL2, further perfectly matching the only available specimen from CP. In fact, the dimensions and proportions of the only P4 available for H. crusafonti perfectly fit the average values for H. laietanus (Table 4), and no significant metrical differences can be found. It can be therefore concluded that the P4 proportions are unlikely to be diagnostic at the species level within Hispanopithecus from the Vallès-Penedès, as previously noted by Ribot et al. (1996). Although a larger sample of H. crusafonti would be required in order to conclusively settle this issue, it should be noted that our results differ from Begun’s (1992) assertion in the original diagnosis of H. crusafonti, according to which it would differ from H. laietanus in displaying relatively broader premolars. The discrepancies from Begun’s (1992) conclusions regarding the P4 are attributable to the inclusion to the H. laietanus hypodigm of additional specimens from CLL2 (Moyà-Solà and Köhler, 1995) and CLL1 (this study), as well as to the removal of IPS1795 [IPS40], which is currently considered non-primate (Harrison, 1991; Ribot et al., 1996; see Table 2 for further details). In contrast, the size and proportions of the P3 (Fig. 5A; Table 4) appear to be diagnostic at the species level, with H. crusafonti displaying absolutely and relatively narrower (i.e., relatively longer) P3 than H. laietanus from CLL1 and CLL2. ANOVA comparisons confirm that such differences are significant regarding BL (p < 0.001) and

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BLI (p < 0.05). Our results therefore further contrast with Begun’s (1992) original diagnosis, according to which the P3 of H. crusafonti would be relatively broader than those of H. laietanus. Such discrepancy is not only attributable to the inclusion of the CLL2 teeth (Moyà-Solà and Köhler, 1995) to the H. laietanus hypodigm, but also to the differences in the measurements taken by the various authors (Begun, 1992; Golpe Posse, 1993; Moyà-Solà and Köhler, 1995; Ribot et al., 1996; this study) on the same specimens. Nevertheless, it should be stressed that, in spite of differences in the measurements, our conclusions for the P3 agree with those reported by Ribot et al. (1996), who relied on the same sample. Unfortunately, the incomplete preservation of the new P4 IPS58334 precludes assessing the proportions of the newly recovered specimen. The taxonomic interpretation of the above-mentioned significant differences between the Can Llobateres and Can Poncic samples is however ambiguous. The CV for P3 breadth of the combined sample (8.4) is higher (thus supporting a taxonomic distinction) than that for gorillas (7.5), chimpanzees (7.0) and H. hoolock (7.0) (Mahler, 1973; this study), but lower (suggesting that the single species hypothesis cannot be discarded) than that of orangutans (9.0) (Mahler, 1973). With regard to P3 proportions, on the basis of simulation analyses of CV based on a sample of extant orangutans, Ribot et al. (1996) concluded that the above-mentioned differences in P3 proportions did not justify a species distinction,

Table 4 Descriptive statistics and ANOVA comparisons for the metrical variables measured in this study for Hispanopithecus laietanus from CLL1 and CLL2 as well as H. crusafonti from CP.

P3 MD P3 BL P3 BLI 3

P A 4

P MD P4 BL P4 BLI 4

P A M1 MD M1 BL 1

M BLI 1

M A M2 MD M2 BL 2

M BLI M2 A M3 MD M3 BL M3 BLI M3 A M2M1 MD M2M1 A

H. H. H. H. H. H. H. H. H. H. H. H. H. H. H. H. H. H. H. H. H. H. H. H. H. H. H. H. H. H. H. H. H. H. H. H. H. H. H. H.

laietanus crusafonti laietanus crusafonti laietanus crusafonti laietanus crusafonti laietanus crusafonti laietanus crusafonti laietanus crusafonti laietanus crusafonti laietanus crusafonti laietanus crusafonti laietanus crusafonti laietanus crusafonti laietanus crusafonti laietanus crusafonti laietanus crusafonti laietanus crusafonti laietanus laietanus laietanus laietanus laietanus crusafonti laietanus crusafonti

N

Mean

SD

3 4 3 4 3 4 3 4 5 1 5 1 5 1 5 1 7 3 7 3 7 3 7 3 5 4 5 4 5 4 5 4 3 3 3 3 3 1 3 1

6.93 6.90 11.70 10.13 169.19 147.26 81.19 69.91 7.02 6.90 10.46 10.50 149.09 152.17 73.40 72.45 9.44 9.50 10.37 11.00 109.87 115.89 98.20 104.57 10.18 10.10 11.18 11.50 110.54 114.58 114.00 116.55 9.83 10.77 111.04 107.02 1.11 0.98 1.17 1.03

0.50 0.52 0.26 0.26 9.36 9.89 7.41 6.41 0.11

5.68 6.07 11.04 9.71 145.95 131.52 62.79 59.70 6.88

95% CI 8.18 7.73 12.36 10.54 192.44 163.00 99.60 80.12 7.16

6.4 6.5 11.4 9.9 159.5 136.8 73.0 64.4 6.9

Range 7.4 7.6 11.9 10.4 178.1 158.5 87.3 79.0 7.2

F

0.43

9.92

11.00

9.8

7.88

139.30

158.87

2.39

70.43

0.56 0.46 0.56 0.46 1.67 5.11 10.83 8.04 1.00 1.13 0.66 0.57 11.50 9.29 14.88 18.09 1.97 1.71 20.01 32.79 0.03 0.05

p

0.007

0.936

61.187

0.001

8.800

0.031

4.680

0.083

1.000

0.374

11.0

0.007

0.937

136.1

157.1

0.128

0.739

76.37

70.6

77.0

0.132

0.735

8.92 8.36 9.85 9.86 108.33 103.19 88.18 84.60 8.94 8.30 10.36 10.59 96.26 99.80 95.52 87.76 4.93 6.52 61.34 25.56 1.03

9.96 10.64 10.89 12.14 111.42 128.59 108.21 124.54 11.42 11.91 12.01 12.41 124.82 129.36 132.48 145.33 14.74 15.01 160.73 188.49 1.18

8.6 9.0 9.4 10.6 108.0 110.0 80.8 95.4 8.8 8.8 10.0 10.9 101.8 105.4 95.0 98.6 8.5 8.8 95.9 74.8 1.1

10.0 9.9 10.9 11.5 112.6 119.8 108.0 110.4 11.2 11.1 11.6 12.2 130.7 127.3 127.7 134.2 12.1 11.9 133.7 140.4 1.1

0.024

0.882

2.868

0.129

8.804

0.018

0.819

0.392

0.013

0.913

0.580

0.471

0.323

0.588

0.054

0.823

13.532

0.067

1.05

1.30

1.1

1.2

5.846

0.137

Abbreviations: MD, mesiodistal length; BL, maximum buccolingual breadth; BLI, breadth/length index, computed as BL/MD
100; A, occlusal area, computed as MD
BL; N, sample size; SD, standard deviation; CI, confidence interval for the mean; F, statistic employed by the ANOVA comparisons; p, significance of the ANOVA comparisons.

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D.M. Alba et al. / Journal of Human Evolution 63 (2012) 231e246

since the coefficient of variation for the combined sample was relatively high but not excessive. Our own analyses for the P3 BLI indicate that the CV for the combined Hispanopithecus sample (9.7) is higher than that of H. hoolock (6.6) but lower than that of P. troglodytes (10.2). Not surprisingly, randomization results indicate that the single species hypothesis cannot be discarded when P. troglodytes is taken as the model of species variation, with simulated CV for this taxon ranging from 4.5 to 17.0, and 64% of replicates showing a greater CV than the Hispanopithecus sample. In contrast, when H. hoolock is taken as the extant model (simulated CV from 2.6 to 10.3), only 3% of replicates show a greater CV than the fossil sample, thus enabling to reject the single species hypothesis. Upper molars Finally, with regard to the molars, the M2 (IPS58339; Fig. 3K) differs from the two available M1 (IPS58337 and IPS58338; Fig. 3I and J) by being larger and more clearly longer on the lingual than on the buccal portion of the crown, and by further displaying a tapering distal lobe that is markedly narrower than the mesial one. The M3 IPS58340 (Fig. 3L), on the contrary, is unusually short, due to the vestigial metacone and reduced talon (particularly on the buccal side), resulting in a clearly oval occlusal contour (much wider than long, and longer on the buccal than on the lingual portion of the crown). In general, the occlusal morphology of the new M1 and M2 agrees well with other Hispanopithecus spp. specimens from the Vallès-Penedès Basin. The protocone is the largest cusp, followed by the paracone and then by the metacone. The preparacrista is short, like the mesial fovea, which is restricted to the buccal moiety of the crown and distally closed by a variously developed hypoparacrista that is not directed towards the protocone apex but to the mesial marginal ridge. There is an extensive and roughly subtriangular central fovea (¼trigon basin), distally closely by an inclined crista obliqua that may be partially disrupted by a marked mesiodistal groove. The distal (trigon basin) is relatively restricted, since the trigon is mainly occupied by the hypocone, which is separated from the rest of the crown by a curved and deep groove that runs from the center of this basin towards the lingual crown wall. It is noteworthy that the new specimens display very reduced molar cingula, being restricted to a short mesiolingual portion of the protocone and the buccal portion of the paracone (more conspicuous in the M2 than in the remaining molars). A similar condition is displayed by some Hispanopithecus molars from the Vallès-Penedès Basin, whereas other specimens, such as IPS18000 from CLL2 (Fig. 7C) as well as IPS1814 and IPS1818 from CP (Fig. 7I and J), display better developed (albeit still narrow) upper molar cingula. Unlike the preceding molars, the morphology of the newly recovered M3 IPS58340 (Figs. 3L and 7A) is quite unusual, and deserves particular consideration (see later), although it should be taken into account that in hominoids this tooth is metrically and morphologically more variable than the preceding molars (Swindler et al., 1998). Detailed comparisons for each molar (Fig. 7) are hindered by the lack of agreement regarding tooth position identification for several isolated Hispanopithecus specimens from the Vallès-Penedès Basin (see Begun et al., 1990; Harrison, 1991; Begun, 1992; Golpe Posse, 1993). Given previous disagreements between these authors, here we follow our own attributions, which are mostly based on the three available tooth rows of Hispanopithecus from the Vallès-Penedès (Fig. 7AeC). The latter show that, compared with M1, M2 are larger and more tapered distally, whereas M3 are characterized (despite variable size and proportions, see later) by a somewhat reduced metacone compared with the preceding molars. Our tooth position attributions for the upper molar sample from the Vallès-Penedès Basin differ in some particular instances from those made by the above-mentioned authors. Thus, regarding the CLL1 material, IPS1844 (Fig. 7F) and

IPS1781 (Fig. 7G) are identified as M1 (Harrison, 1991; see also; Begun et al., 1990) instead of M2 (Golpe Posse, 1993), whereas IPS1794 (Fig. 7K) is identified as an M2 (Begun et al., 1990; Golpe Posse, 1993) instead of as an M1 (Harrison, 1991), and IPS1771 (Fig. 7L) is tentatively identified as an M2 (Harrison, 1991) instead of an M3 (Begun et al., 1990; Golpe Posse, 1993; see further details in Table 2). Similarly, with regard to the CP material, IPS1814 (Fig. 7I) is identified as an M1 instead of as an M2 (Begun, 1992) or an M3 (Harrison, 1991; Golpe Posse, 1993), whereas IPS1815 (Fig. 7M), IPS1820 (Fig. 7N) and IPS1821 (Fig. 7O) are identified as M2 (in agreement to Harrison, 1991, and/or Begun, 1992, depending on the case) instead of as an M1 (IPS1815) or as M3 (IPS1820 and IPS1820) (Golpe Posse, 1993). On the basis of the tooth position identifications discussed above, dental proportions of the new M1 (Fig. 6C) closely resemble several previously known specimens of both H. laietanus from CLL1 and CLL2 (N ¼ 5) as well as H. crusafonti from CP (N ¼ 3), although the latter taxon displays on average larger (particularly broader) M1 than H. laietanus (Table 4). ANOVA comparisons confirm that both taxa significantly differ regarding BLI of the M1 (p < 0.05) due to absolutely broader molars in H. crusafonti, although differences regarding absolute buccolingual breadth are not significant (p ¼ 0.129), probably due to small sample size and the existence of some overlap (Table 4). The CV for the combined Hispanopithecus sample regarding M1 length (5.5) and breadth (5.7) are lower than those of extant great apes (Mahler, 1973) and only slightly higher than those for H. hoolock (respectively, 5.4 and 4.4; this study), whereas the BLI CV for the combined sample (3.7) is lower than those of both chimpanzees (5.2) and H. hoolock (5.2) (this study). Like in the case of P3 proportions, thus, the taxonomic interpretation of the significant differences in M1 proportions between the Can Llobateres and Can Poncic samples is somewhat ambiguous. The dimensions and proportions of the newly available M2 (Fig. 6C), in turn, closely resemble previously known specimens of both H. laietanus from CLL2 and H. crusafonti from CP, and to a large extent the two specimens previously available from CLL1 as well. Although the CP sample of M2 (N ¼ 4) shows the same tendency towards broader dimensions compared with the H. laietanus sample (N ¼ 5), the overlap is greater than regarding the M1, and ANOVA comparisons indicate that, on the basis of the currently available sample, differences are not significant for either BL or BLI (Table 4). With regard to the size discrepancy between the M2 and the M1, statistical comparisons are not significant due to small sample size. However, it is noteworthy that the tooth row from CLL1 reported here shows an even greater discrepancy (1.13 for MD, and 1.22 for A) than the IPS18000 individual from CLL2, resulting in an average discrepancy for H. laietanus (1.11 for MD and 1.17 for A) that is higher than that displayed by the holotype of H. crusafonti (0.98 for MD and 1.03 for A; see also Table 4). As mentioned above, the new M3 from CLL1 (Figs. 3L and 7A) displays an unusual tricuspid occlusal morphology, resulting in quite striking proportions. The presence of tricuspid M3 is not exceptional amongst extant hominoids, where the reduction of the hypocone from M1 to M3 (sometimes leading to its complete disappearance) is frequent (Swindler et al., 1998; DMA, Personal observation). What is most striking in IPS58340 is that the tricuspid morphology is due to the lack of the metacone instead of the hypocone, giving to this tooth a P3-like morphology, although an attribution of this tooth position is clearly precluded by the presence of a well-developed hypocone, among other features. This M3 most closely resembles H. laietanus IPS1772 (Fig. 7B) from CLL1, which also shows (albeit to a lesser extent) a reduced metacone, although in the former specimen the crown is absolutely and relatively much wider, and the distobuccal portion of the crown is more markedly reduced. Both specimens markedly differ from

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243

Figure 7. Molar teeth of Hispanopithecus laietanus from CLL1 recovered during the 2011 field season, compared with other homologous specimens of H. laietanus from CLL1 and CLL2, as well as H. crusafonti from Can Poncic (CP). A. Composite left M1eM3 series IPS58338eIPS58340 from CLL1; B. Left M3 IPS1772 from CLL1; C. Right M1eM3 series IPS18000.5 (reversed) from CLL2; D. Left M1eM2 series IPS1798 (holotype) from CP; E. Right M3 IPS1812 (reversed) from CP; F. Right M1 IPS1844 (reversed) from CLL1; G. Left M1 IPS1781 from CLL1; H. Left M1 IPS1788 from CLL1; I. Left M1 IPS1814 from CP; J. Left M1 IPS1818 from CP; K. Left M2 IPS1794 from CLL1; L. Left M2? IPS1771 from CLL1; M. Right M2 IPS1815 from CP; N. Right M2 IPS1820 (reversed) from CP; O. Right M2 IPS1821 (reversed) from CP.

H. laietanus IPS18000 (Fig. 7C) from CLL2 (Moyà-Solà and Köhler, 1995), which displays a much longer crown with a welldeveloped talon, most similar to the M2 of the same and other individuals such as IPS58339 (Figs. 3K and 7A). The single, partial M3 of H. crusafonti (Fig. 7E) shows intermediate proportions, although differing from both the CLL1 and CLL2 specimens by the more median position of the hypocone and the better developed metacone. Unfortunately, the single available specimen of H. crusafonti is incomplete, thus precluding statistical comparisons between both samples. In any case, the fact that IPS58339 resembles IPS1772 in length and IPS18000 in breadth suggests that, most likely, we are merely sampling the extremes of a more continuous range of variation within a single taxon. If correct, such large variability in M3 size and proportions should warn us against basing taxonomic attributions on the basis of the proportions of this tooth. Similar differences can be found in the preceding molars, but to a much lesser extent. This is best illustrated by IPS1771 (Fig. 7L), which was identified as an M3 by Begun et al. (1990) and Golpe Posse (1993), probably due to the marked reduction of the talon

and the resulting high BLI. However, as noted by Harrison (1991), this specimen is more likely attributable to an M2, given the presence of both mesial and distal contact facets. This precludes the attribution of this specimen to an M3, unless it is advocated that a supernumerary distomolar (or M4) was present. This is certainly possible given their occasional occurrence in extant hominoids and other primates (Mahler, 1973; DMA, Personal observation), but highly unlikely given their low prevalence, which is generally below 5% (Ackermann et al., 2006, and references therein). Discussion The systematics and alpha-taxonomy employed in this paper follows Alba (in press; see also Casanovas-Vilar et al., 2011: SI Appendix Text 1 and Table 2), according to which two distinct hominoid species are recorded during the Late Miocene in the Vallès-Penedès Basin: H. (H.) laietanus Villalta Comella and Crusafont Pairó, 1944, and Hispanopithecus (Hispanopithecus) crusafonti Begun, 1992. These species would differ at the subgenus

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level from Hispanopithecus (Rudapithecus) hungaricus (Kretzoi, 1969) from Rudabánya (Hungary), and at the genus level from Dryopithecus fontani from Saint Gaudens (France), Abocador de Can Mata (Spain) and elsewhere (see also Moyà-Solà et al., 2009b, for further justification, and both Begun, 2009, and Pickford, 2012, for different but frequently contrasting opinions). Many decades ago, the few dental hominoid remains initially recovered from CLL1 were attributed to H. laietanus (Villalta Comella and Crusafont Pairó, 1944). However, after the find of additional material, two additional taxa (‘Dryopithecus piveteaui’ and ‘Rahonapithecus sabadellensis’) were erected (Crusafont and Hürzeler, 1961, 1969; Crusafont-Pairó and Golpe-Posse, 1973), and a large male upper canine was also attributed to Dryopithecus cf. indicus d currently Sivapithecus indicus (Crusafont-Pairó and Golpe-Posse, 1973; Golpe Posse, 1982, 1993). The two former nominal taxa, however, must be considered nomina nuda (e.g., Szalay and Delson, 1979; Begun et al., 1990; Alba and Moyà-Solà, 2012), and since the early 1990s the sample from CLL1 and CLL2 has been customarily attributed to a single species (Begun et al., 1990; Harrison, 1991; Begun, 1992, 2002; Moyà-Solà and Köhler, 1993, 1995, 1996; Andrews et al., 1996; Ribot et al., 1996; Cameron, 1997, 1999; Alba et al., 2011d; Casanovas-Vilar et al., 2011; Alba and Moyà-Solà, 2012; see Pickford, 2012, regarding a different interpretation, since he considered Neopithecus brancoi as a valid taxon present at CLL1). In contrast, there is ongoing discussion on whether H. crusafonti from CP must be considered a distinct species from H. laietanus (see later). The dental remains described here fit quite well with the morphology and metrical variability previously known for H. laietanus, thus being attributed to that species. At the same time, the newly reported remains from CLL1 show additional intraspecific variation regarding several teeth (especially the dP3, I1, I2, P4 and M3), which were poorly represented at this and other VallèsPenedès localities. The taxonomic distinction between H. laietanus and H. crusafonti (Begun, 1992; see also; Begun et al., 1990; Begun, 2002) has proven controversial, being supported by several authors (Cameron, 1999; Moyà-Solà et al., 2009b; Alba and Moyà-Solà, 2012; Pickford, 2012; Alba, in press), but only tentatively accepted by Andrews et al. (1996), and openly disputed by Harrison (1991) and Ribot et al. (1996). Moyà-Solà et al. (2009b), Begun (2009) and Alba (in press) recently allocated both taxa into the genus Hispanopithecus instead of Dryopithecus, whereas Pickford (2012) suggested that H. crusafonti (which he maintained within Dryopithecus) might be a junior synonym of Udabnopithecus garedziensis from Georgia, further noting dental similarities with Anoiapithecus brevirostris from the Middle Miocene of the VallèsPenedès Basin (see Moyà-Solà et al., 2009a). Providing a full assessment of the taxonomic validity of H. crusafonti from CP (and maybe Teuleria del Firal; Begun, 1992, 2002) as a distinct species (or even genus) from H. laietanus is outside the scope of this paper. The latter would require evaluating the few lower teeth available from CP, as well as comparing these samples with all the other European fossil hominoid taxa recognized by the various authors (including the Middle Miocene genera Pierolapithecus, Anoiapithecus and Dryopithecus from the Vallès-Penedès Basin, France and perhaps elsewhere; see MoyàSolà et al., 2004, 2009a,b; Alba and Moyà-Solà, 2012; Pickford, 2012; Alba, in press). This is outside from the scope of this paper, which merely intends to evaluate some of the diagnostic criteria purportedly distinguishing H. crusafonti from H. laietanus in the light of the newly reported remains from CLL1, given the previous contention that they were merely attributable to intraspecific variation (Ribot et al., 1996). According to its original diagnosis (Begun, 1992; see also Begun, 2002), H. crusafonti would differ from other Hispanopithecus species by the higher-crowned

and relatively narrower I1 with well-developed median and mesial lingual pillars; similar occlusal proportions between the M1 and M2; lack of molar cingula; relatively broader upper premolars and molars (only compared with H. laietanus); and relatively broader male C1, as well as several additional differences regarding the lower molars, which cannot be further evaluated in the light of the new finds from CLL1. The three available I1 from CP display a characteristic lingual morphology, with a marked median lingual pillar and a strong mesial ridge, and further display a relatively narrow and high crown, whereas the four previously available specimens from CLL1 and CLL2 display a shelf-like, basally swollen lingual cingulum and vertical enamel ridges instead of a pillar, as well as a more brachyodont crown (Begun, 1992; Pilbrow, 2006; Pickford, 2012). The new I1 from CLL1 most closely resembles the H. laietanus morphology in crown height and lingual morphology (presence of a shelf-like bulge indistinct from the cingulum), even though it shows that the presence of lingual enamel folds and crenulations in this taxon is variable, since IPS61398 displays instead a faint lingual pillar that, unlike in H. crusafonti, is not continuous with the basal bulge and is not separated from the mesial and distal ridges by marked clefts. Similarly, the new I2 from CLL1, together with IPS1843 (reinterpreted as a permanent lateral incisor), shows a large degree of intraspecific variation in I2 morphology within H. laietanus than previously recognized. Admittedly, none of the specimens displays a lingual pillar, but the development of the lingual bulge is very variable, as it is to some degree the crown robustness and peg-shaped morphology. Several authors (Ribot et al., 1996; Pilbrow, 2006) have noted that the lingual morphology of the two upper incisors is highly variable amongst extant hominoids. Pilbrow (2006), in particular, showed that features such as the presence of lingual pillars are variable not only within species and subspecies, but even within populations, further displaying different frequencies in the I1 and I2 of a single taxon. Pilbrow (2006) therefore concluded that patterns of variation in extinct taxa should be studied before employing such lingual incisor features as taxonomically diagnostic features, which is often hampered by small available sample sizes. In this sense, the addition of IPS61398 to the H. laietanus hypodigm, despite showing a greater variation in lingual traits than previously recognized, reinforces the view that H. crusafonti can be distinguished from H. laietanus on the basis of I1 crown height and the lingual incisor traits, and therefore tentatively supports a taxonomic distinction between these taxa (Begun, 1992; Pickford, 2012). The available samples, however, are still too small to rule out the possibility that this merely reflects a sampling effect (Ribot et al., 1996; Pilbrow, 2006), or the possibility that H. crusafonti and H. laietanus merely differ in their respective frequencies of incisor lingual traits, as it is found in extant hominoids (Pilbrow, 2006). The latter possibility would be further supported by the fact that both incisor morphs can be found within the sample of Hispanopithecus hungaricus from Rudabánya, Hungary (Pilbrow, 2006), unless Pickford’s (2012) contention that two different hominoid taxa are represented within the latter sample is accepted. Overall, the two (central and lateral) upper incisors reported here enable us to better evaluate the degree of variation in incisor morphology displayed by H. laietanus. This should warn us against putting much significance on such traits until larger samples are available, although the new I1 certainly supports, albeit tentatively, a taxonomic distinction for the CP sample. In turn, the new material from CLL1 shows that the presence of upper molar cingula is variable in both H. laietanus and H. crusafonti, thus resembling the variation that can be seen in extant great ape genera (especially African apes; Swindler et al., 1998). The previous claim (Begun, 1992; Cameron, 1999) that

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H. crusafonti is characterized by more reduced cingula than H. laietanus must be therefore deemed incorrect, as shown not only by the presence of continuous buccal and even lingual cingula in the upper molars of H. crusafonti, but also by the reduced cingula displayed by the new specimens of H. laietanus. We hence concur with the previous conclusion by Ribot et al. (1996) that the development of upper molar cingula is not a diagnostic feature of H. crusafonti, since this taxon does not differ in this respect from specimens attributed to H. laietanus. With regard to the purported differences in dental size and proportions proposed by Begun (1992), Ribot et al. (1996) concluded that the CP upper cheek teeth were not significantly broader than those of H. laietanus, and further attributed to mere sampling effect the tendency of the former to display more similar proportions between the M1 and the M2. Given the differences in tooth position identification discussed in this paper, together with the addition of the newly reported remains to the H. laietanus hypodigm, we performed new statistical analyses to test this issue. As reported above, our results contradict Begun’s (1992) claims that H. crusafonti differs from H. laietanus by displaying relatively broader upper premolars, and rather confirm Ribot et al.’s (1996) conclusions that significant differences can be found regarding P3 but not P4 proportions. Our results concur with those of the latter authors, by indicating that H. crusafonti displays absolutely and relatively narrower P3 compared with H. laietanus. Inferring whether this difference reflects a taxonomic distinction is however ambiguous, given that extant species display different ranges of variation for P3 dimensions and proportions. According to our results, the metrical variation displayed by the combined Can Llobateres and the Can Poncic samples for this tooth only enables to reject the single species hypothesis in some instances. Regarding the purported differences in molar proportions, this study shows that significant differences can be only found for the M1, with H. crusafonti displaying relatively broader molars as previously noted by Begun (1992), whereas the M2 shows the same tendency as the M1 but with a larger overlap. Nevertheless, the range of variation displayed by the combined sample regarding M1 size and proportions does not exceed that displayed by extant hominoid species, thus rendering its taxonomic interpretation quite ambiguous. Similarly, the new material further reinforces the purported diagnostic feature proposed by Begun (1992), but latter dismissed by Ribot et al. (1996), according to which H. crusafonti would differ from H. laietanus by a lower size discrepancy between the second and first upper molars. Nevertheless, given the small sample sizes, additional associated tooth rows would be required to assess the variability of this feature, especially within the CP sample, since only the holotype specimen is available. Finally, the available M3 of H. laietanus suggests that the occlusal proportions of this tooth position are too variable to serve as a valid taxonomic criterion. The presence of a more median hypocone and better developed metacone might distinguish H. crusafonti from H. laietanus, but this cannot be conclusively asserted given the small sample size available for the former. Summary and conclusions Overall, the reported results for the first systematic excavation carried out in CLL1 since 1981 unambiguously confirm that the fossiliferous layers rich in fossil primate remains are not exhausted. Such circumstance is promising for the discovery of additional remains of H. laietanus at CLL1 in the near future. New finds of this taxon would hopefully provide additional information on its craniofacial and postcranial anatomy, which are currently mainly known from the face and associated partial postcranial skeleton from CLL2 (Moyà-Solà and Köhler, 1993, 1995, 1996; Almécija et al.,

245

2007), as well as from a female partial skeleton from Can Feu (Alba et al., 2011a; Alba et al., in press). Moreover, the 12 new dental specimens from CLL1 reported here represent a significant addition to the hypodigm of H. laietanus. Given the significant role played by dental morphology in hominoid taxonomy, enlarging the available samples for the several putative distinct taxa is of utmost significance to evaluate the variability displayed by the various populations, which is essential for adequately assessing their alphataxonomy. In particular, the new dental remains from CLL1 reported here show some degree of variation for several teeth that were previously poorly represented among the Vallès-Penedès samples, especially the dP3, the I1, the I2, the P4 and the M3. The latter tooth, in particular, shows a large variation in metacone and talon development, thus suggesting that it would be of little use for making taxonomic distinctions even if the sample was enlarged in the future. The I1 and the I2, in turn, show greater morphological variation than previously documented, thus highlighting the contention that, for readily employing lingual features as a taxonomic criterion, larger samples would be required in order to adequately evaluate intraspecific variability (Ribot et al., 1996; Pilbrow, 2006). At the same time, however, the new upper central incisor tentatively reinforces the view that H. laietanus and H. crusafonti consistently differ in the development of incisor lingual traits, as originally advocated by Begun (1992). Moreover, the attribution of most of the new specimens to a single individual enables to revise previous tooth position identifications for the upper molars of H. laietanus and H. crusafonti, as well as to further assess the upper molar diagnostic criteria previously proposed by Begun (1992) to distinguish the purported species H. crusafonti from H. laietanus (Begun, 1992). The new specimens from CLL1 strengthen the view that, as previously advocated by other authors (Ribot et al., 1996), the development of upper molar cingula within both taxa is too variable to be of taxonomic value. In contrast, other features proposed by Begun (1992), such as upper premolar and molar proportions, tentatively stand as distinguishing characters of H. crusafonti and therefore tentatively support its distinct species status compared with H. laietanus, although only regarding P3 and M1 proportions, as well as M2eM1 size discrepancy. However, as noted by Ribot et al. (1996), differences in P3 proportions are just the opposite from those noted in the original diagnosis of H. crusafonti, and both P3 and M1 proportions for the combined sample do not exceed the range of variation of many extant hominoid species, making its taxonomic interpretation somewhat ambiguous. Ultimately, such problems stem from the fact that comparisons are based on relatively small sample sizes, and should be hence subjected to further scrutiny as new hominoid dental remains from the Late Miocene of the Vallès-Penedès become available in the future. Acknowledgments Fieldwork at CLL1 in 2011 was funded by the National Geographic Society (fieldwork grant #8910-11), the Generalitat de Catalunya (fieldwork grant 61636/2010) and the Spanish Ministerio de Ciencia e Innovación (CGL2008-00325/BTE). This research was further supported by the Generalitat de Catalunya (2009 SGR 754 GRC, and BP-A 00226 to SA) and the Ministerio de Ciencia e Innovación (CGL2010-21672/BTE, CGL2011-28681, RYC-2009-04533 to DMA, and JCI-2010-08241 to ICV). We thank the Preparation Division of the ICP for the excellent preparation of the specimens, Marta March for assistance with the ICP collections, Eileen Westwig (AMNH) for access to extant comparative material under her care, and the Associate Editor and Terry Harrison for helpful comments and suggestions on a previous version of this paper. Finally, we are

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D.M. Alba et al. / Journal of Human Evolution 63 (2012) 231e246

also deeply grateful to all the ICP staff and volunteers from elsewhere that took place in the 2011 field season at CLL1: E. Acosta, A. Aliaga, E. Blaya, D. Campos, R. Carmona, M. Delfino, D. DeMiguel, L. Feliu, C. Ferrer, N. Font, J. Fortuny, M. Furió, R. Garcia Artigas, M. Llenas, S. Madeddu, I. Martínez Laborda, J. Madurell-Malapeira, L. Marino, J.M. Méndez, R. Minwer-Barakat, M. Navarro, P. Obradó, D.B. Pacheco, M. Pina, S. Pineda, I. Roig, C. Rotgers, I. Sucarrats, I. Susanna, and M. Tallman.

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