- Email: [email protected]
Spore and pollen types of the lower cretaceous in Patagonia (Argentina)
Review of Palaeobotany and Palynology
Elsevier Publishing Company, Amsterdam - Printed in The Netherlands
SPORE A N D POLLEN TYPES OF THE LOWER CRETACEOUS IN PATAGONIA (ARGENTINA) SERGIO ARCHANGELSKY AND JUAN C. GAMERRO Division of Palaeobotany, La Plata University, Buenos Aires (Argentina)
(Received August 28, 1966)
SUMMARY
The Baquer6 Formation of Santa Cruz Province, Argentina, has proved to be rich in spore-pollen content. So far, 46 species have been determined, 10 of them being new. Three other groups of species are recognized: (1) those which are common only with Australia (and Antarctica); (2) those common with northern provinces only; and (3) those which are cosmopolitan (present in northern as well as in southern provinces). The age of the formation, judging by the whole assemblage, is Lower Cretaceous, more precisely Barremian to Aptian. No true angiosperms occur in this assemblage.
INTRODUCTION The authors are at present engaged in the study of the spores and pollen grains found in twelve beds of the Lower Cretaceous Baquer6 Formation in Santa Cruz Province, Argentina. More than fifty species have been found so far, and they are mainly represented by spores. Pollen grains are all gymnosperms, and although represented by fewer types, they dominate in the assemblages. The Lower Cretaceous age of the formation has been established mainly on the ground of pollen-spore assemblage of already known species from other regions, most of which are represented in Fig. 1.
TECHNIQUE The sediments, mainly tufts, were treated with H F for 48 h, washed with hot 15~o HC1, warm 1-2~o K O H and acetolyzed. When needed, separation with bromoform-acetone (s.g. 2.2) was used. The residues were mounted in glycerine jelly. Single grains were also prepared. Rev. Palaeobotan. Palynol., 1 (1967) 211-217
211
MATERIAL STUDIED The slides, residues a n d original sediments belong to the P a l a e o b o t a n i c a l Collection o f the L a P l a t a M u s e u m o f N a t u r a l History, Argentina.
RESULTS The following species have been recognized so far (see Plates I a n d 1I): Spores Densoisporites velatus (WEYLAND et K RIEGER) KRASNOVA D. corrugatus ARCHANGELSKY et GAMERRO Cyatheacidites tectifera ARCHANGELSKY et GAMERRO Aequitriradites spinulosus (COOKSON et DETTMANN) COOKSON et DETTMANN A. verrucosus (CooKSON et DETTMANN) COOKSON et DETTMANN A. baculatus D~JRING Polypodiaceoisporites elegans ARCHANGELSKY et GAMERRO Camarazonosporites microalveolatus ARCHANGELSKY et GAMERRO Antulsporites baculatus ARCHANGELSKY et GAMERRO Foraminisporis dailyi (CooKsoN et DETTMANN) DETTMANN Muricingulisporis annulatus ARCHANGELSKY et GAMERRO Contignisporites cooksonii (BALME) DETTMANN
Taurocusporites segmentatus STOVER Rouseisporites reticulatus POCOCK Trilobosporites apiverrucatus COUPER T. trioreticulosus COOKSON et DETTMANN T. purverulentus (VERBITSKAYA) DETTMANN
PLATE I
A. B. C. D. E. F. G. H. I. J. K. L. M. N. O.
Trilobosporites trioreticulosus COOKSONet DETTMANN T. apiverrucatus COUPER Densoisporites velatus (WEYLANDet KmEGEV,)KRASNOVA Muricingulisporis annulatus ARCHANGELSKYet GAr~ERRO Polypodiaceoisporites elegans ARCHAI'~GELSKVet GAMERRO Cicatricosisporites australiensis (CooKsoN) POTONI~ Trilobosporites purverulentus (VERBITRKAYA)DETTMANN Sestrosporites pseudoalveolatus (CouI'~R) DETTMANN Aequitriradites spinulosus (COoKSONet DETTMANN)COOKSONet DETTMANN Cicatricosisporites hughesii DETrMANN Gleicheniidites sp. Cyatheacidites tectifera ARCHANGELSKYet GAMERRO Lycopodiumsporites austroclavatidites (CooKSON) POTON~ Foraminisporis dailyi (COOKSONet DEa'TMANN)DETTMANN Schizosporis reticulatus COOKSONet DETTMANN
Magnification × 600. 212
Rev. Palaeobotan. Palynol., 1 (1967) 211-217
PLATE I
Rev. Palaeobotan. Palynol., 1 (1967) 211-217
213
Sestrosporites pseudoalveolatus (COUPER) DETTMANN Cicatricosisporites australiensis (CooKSON) POTONI~ C. hughesii DETTMANN C. cf. ethmos DELCOURT et SPRUMONT C. giganteus ARCHANGELSKYet GAMERRO C. ticoensis ARCHANGELSKYet GAMERRO C. baqueroensis AR.CHANGELSKYet GAMERRO C. annulatus ARCHANGELSKYet GAMERRO Cyathidites australis COUPER Leptolepidites verrucatus COUPER Osmundacidites wellmanii COUPER Ceratosporites equalis COOKSON et DETTMANN Kuylisporites lunaris COOKSON et DETTMANN Lycopodiumsporites austroclavatidites (COOKSON) POTONI~ Staplinisporites caminus (BALME) POCOCK Concavissimisporites v e r r u c o s u s DELCOURTet SPRUMONT Pollen A lisporites grandis (CooKsoN) DETTMANN Podocarpidites ellipticus COOKSON Microcachryidites antarcticus COOKSON Ginkgocycadophytus nitidus (BALME) DE JERSEY Classopollis torosus (REISSlNGER) COUPER Araucaricites australis COOKSON Caytonipollenites pallidus (REISSINGER) COUPER Trisaccites microsaccatum (CouPER) COUPER Clavatipollenites hughesii COUPER lnaperturopollenites limbatus BALME Zonalapollenites dampieri BALME Z. trilobatus BALME lncertae Schizosporis reticulatus COOKSON et DETTMANN Among the material not identified so far, are trilete and monolete spores, saccate and monocolpate grains.
DISCUSSION The present material is of a particular interest because it was found in a new geographic area where palynological data are lacking. The Lower Cretaceous material so far available for comparison occurs in Australia, North America, Europe and Asia. Patagonia belongs to the palaeogeographic unit known as Gondwana, where similar taphofloras existed during the Palaeozoic and Mesozoic eras. The palaeobotanical data based on megascopic remains are now fully confirmed by the palynological results, as far as Australia (and Antarctica) and Pata214
Rev. Palaeobotan. Palynol., I (1967) 211-21 7
Stratigraphlcal Geographical distribution
~
distribution
O
C
c
,_
c
.u_
.~
o
>
"-
~
m
>
.~ The Netherlands Great Britain Germany Australia
O
O
-r
Species
O
rn
m
<
<
DU
$estrosporites ~$eudoalveolotus
a
Canada U.S.A. Australia U.SA. Canada Great Britain Canada ~ustralia U.S.S.R. t~ustralia U.S.S.R. Canada
Rouseisporites reticulotus Taurocuspor/tes segrnentatus Trilobospor/tes apiverrucatus Trilobosporites ourverulentus
m m m
TrHobospor/t • s trioreticulosus Foraminisporis
Australia
U.SA. Australia U.S.S.R. Germany Great Britain U.S.S.R. U.S.A. Australia Tunisia Australia U.S.S.R.
dailyi
Contignisporites cooksonii "
Oenso/sporites velatus
.m
Aequitriradites splnulosus
Canada Germany
U.S.A. Australia U.S.S.R. Germany
Aequ/tr/rad/tes verrucosus
Aequitriradites boculatus Schizosporis reticulatus Clavatip.ollenites hughestt Classopoll/s torosus ~._ Microcachryidites v antarcticus
Germany Australia Canada Great Britain U.S.A. U.S.A. Great New
Britain Zealand
Australia New Zealand Australia
"
~
Trisaccites rnicrosaccaturn
Fig.1. Pollen-spore assemblage of already known species from other regions indicating their geologic range.
Cicatricosisporites hughesii, Alisporites grandis, Podocarpidites ellipticus, Trisaccites microsaccatum, Microcachryidites antarcticus, Inaperturopollenites limbatus. However, some taxa found in Patagonia are known to occur in other regions but the Gondwana: Taurocusporites segmentatus, Trilobosporites apiverrucatus, Aequitriradites baculatus, gonia are concerned. Some taxa are c o m m o n only to both areas:
Rev. Palaeobotan. Palynol., 1 (1967) 211-217
215
PLATE II
2l 6
Rev. Palaeobotan. Palynol., I (1967) 211-217
Cicatricosisporites ethmos, Concavissiml~porit~ verrucostts and Clavatipollenites hughesii. Their presence indicates that the Patagonian assemblage, although closely comparable with the Australian, has some elements in common with other palaeobotanical regions, and therefore, some relations among Patagonia and those regions, which are not known for Australia, have existed. On the other hand, a high percentage of endemic taxa indicates a defined character of the Lower Cretaceous vegetation in Patagonia. This is also confirmed by the study of megascopic taxa found in the same formation (more than seventy species, many with cuticles preserved). The spore assemblage seems to be rather cosmopolitan, many species being known from different northern and southern areas;they are usually represented by few individuals. Many species of pollen grains, which are known in other areas, are essentially of "gondwanic" affinity, specially the saccate grains. The gymnosperms are represented by fewer species than the pteridophytes (and bryophytes) but they markedly dominate the palynological spectrum. The age of the Baquer6 Formation may be deduced from Fig.1. The most useful species for stratigraphic purposes so far determined are included and their geologic range in every country (or region) is recorded. The vertical bands corresponding to the Barremian andAptian stages cross most of the horizontal lines of records (36 for the Barremian and 34 for the Aptian). It is difficult to decide the value of lowest and uppermost records of some individual taxa, in order to precise age determination. Aequitriradites baculatus, known in Germany, seems to extend only up to the end of the Barremian, but other similar records are still necessary. On the other hand, some taxa known from more than one region, seem to have appeared during the Barremian" Taurocusporites segmentatus, Trilobosporites purverulentus, T. trioreticulosus. The lowest possible age of our assemblage is thus Barremian. Some other taxa, on the other hand, extend their range up to the Albian. The absence of typical angiosperms (megascopic and microscopic material) excludes an Albian age and puts the possible top of our assemblage in the Aptian.
P L A T E II A. Inaperturopollenites sp. B. Clavatipollenites hughesii COOPER C. Ginkgocycadophytus sp. D. Monosaccate grain E. lnaperturopollenites limbatus BALME(× 700) F. Alisporites grandis (COOKSON)DETTMANN G. Microcachryidites antarcticus COOKSON H. Caytonipollenites pallidus (REISSINGER) I. Classopollis sp. ( × 700) J. Zonalapollenites trilobatus BALME Magnification x 600 (except where otherwise stated). Rev. Palaeobotan. Palynol., 1 (1967) 211-217
217
Elsevier Publishing Company, Amsterdam - Printed in The Netherlands
SPORE A N D POLLEN TYPES OF THE LOWER CRETACEOUS IN PATAGONIA (ARGENTINA) SERGIO ARCHANGELSKY AND JUAN C. GAMERRO Division of Palaeobotany, La Plata University, Buenos Aires (Argentina)
(Received August 28, 1966)
SUMMARY
The Baquer6 Formation of Santa Cruz Province, Argentina, has proved to be rich in spore-pollen content. So far, 46 species have been determined, 10 of them being new. Three other groups of species are recognized: (1) those which are common only with Australia (and Antarctica); (2) those common with northern provinces only; and (3) those which are cosmopolitan (present in northern as well as in southern provinces). The age of the formation, judging by the whole assemblage, is Lower Cretaceous, more precisely Barremian to Aptian. No true angiosperms occur in this assemblage.
INTRODUCTION The authors are at present engaged in the study of the spores and pollen grains found in twelve beds of the Lower Cretaceous Baquer6 Formation in Santa Cruz Province, Argentina. More than fifty species have been found so far, and they are mainly represented by spores. Pollen grains are all gymnosperms, and although represented by fewer types, they dominate in the assemblages. The Lower Cretaceous age of the formation has been established mainly on the ground of pollen-spore assemblage of already known species from other regions, most of which are represented in Fig. 1.
TECHNIQUE The sediments, mainly tufts, were treated with H F for 48 h, washed with hot 15~o HC1, warm 1-2~o K O H and acetolyzed. When needed, separation with bromoform-acetone (s.g. 2.2) was used. The residues were mounted in glycerine jelly. Single grains were also prepared. Rev. Palaeobotan. Palynol., 1 (1967) 211-217
211
MATERIAL STUDIED The slides, residues a n d original sediments belong to the P a l a e o b o t a n i c a l Collection o f the L a P l a t a M u s e u m o f N a t u r a l History, Argentina.
RESULTS The following species have been recognized so far (see Plates I a n d 1I): Spores Densoisporites velatus (WEYLAND et K RIEGER) KRASNOVA D. corrugatus ARCHANGELSKY et GAMERRO Cyatheacidites tectifera ARCHANGELSKY et GAMERRO Aequitriradites spinulosus (COOKSON et DETTMANN) COOKSON et DETTMANN A. verrucosus (CooKSON et DETTMANN) COOKSON et DETTMANN A. baculatus D~JRING Polypodiaceoisporites elegans ARCHANGELSKY et GAMERRO Camarazonosporites microalveolatus ARCHANGELSKY et GAMERRO Antulsporites baculatus ARCHANGELSKY et GAMERRO Foraminisporis dailyi (CooKsoN et DETTMANN) DETTMANN Muricingulisporis annulatus ARCHANGELSKY et GAMERRO Contignisporites cooksonii (BALME) DETTMANN
Taurocusporites segmentatus STOVER Rouseisporites reticulatus POCOCK Trilobosporites apiverrucatus COUPER T. trioreticulosus COOKSON et DETTMANN T. purverulentus (VERBITSKAYA) DETTMANN
PLATE I
A. B. C. D. E. F. G. H. I. J. K. L. M. N. O.
Trilobosporites trioreticulosus COOKSONet DETTMANN T. apiverrucatus COUPER Densoisporites velatus (WEYLANDet KmEGEV,)KRASNOVA Muricingulisporis annulatus ARCHANGELSKYet GAr~ERRO Polypodiaceoisporites elegans ARCHAI'~GELSKVet GAMERRO Cicatricosisporites australiensis (CooKsoN) POTONI~ Trilobosporites purverulentus (VERBITRKAYA)DETTMANN Sestrosporites pseudoalveolatus (CouI'~R) DETTMANN Aequitriradites spinulosus (COoKSONet DETTMANN)COOKSONet DETTMANN Cicatricosisporites hughesii DETrMANN Gleicheniidites sp. Cyatheacidites tectifera ARCHANGELSKYet GAMERRO Lycopodiumsporites austroclavatidites (CooKSON) POTON~ Foraminisporis dailyi (COOKSONet DEa'TMANN)DETTMANN Schizosporis reticulatus COOKSONet DETTMANN
Magnification × 600. 212
Rev. Palaeobotan. Palynol., 1 (1967) 211-217
PLATE I
Rev. Palaeobotan. Palynol., 1 (1967) 211-217
213
Sestrosporites pseudoalveolatus (COUPER) DETTMANN Cicatricosisporites australiensis (CooKSON) POTONI~ C. hughesii DETTMANN C. cf. ethmos DELCOURT et SPRUMONT C. giganteus ARCHANGELSKYet GAMERRO C. ticoensis ARCHANGELSKYet GAMERRO C. baqueroensis AR.CHANGELSKYet GAMERRO C. annulatus ARCHANGELSKYet GAMERRO Cyathidites australis COUPER Leptolepidites verrucatus COUPER Osmundacidites wellmanii COUPER Ceratosporites equalis COOKSON et DETTMANN Kuylisporites lunaris COOKSON et DETTMANN Lycopodiumsporites austroclavatidites (COOKSON) POTONI~ Staplinisporites caminus (BALME) POCOCK Concavissimisporites v e r r u c o s u s DELCOURTet SPRUMONT Pollen A lisporites grandis (CooKsoN) DETTMANN Podocarpidites ellipticus COOKSON Microcachryidites antarcticus COOKSON Ginkgocycadophytus nitidus (BALME) DE JERSEY Classopollis torosus (REISSlNGER) COUPER Araucaricites australis COOKSON Caytonipollenites pallidus (REISSINGER) COUPER Trisaccites microsaccatum (CouPER) COUPER Clavatipollenites hughesii COUPER lnaperturopollenites limbatus BALME Zonalapollenites dampieri BALME Z. trilobatus BALME lncertae Schizosporis reticulatus COOKSON et DETTMANN Among the material not identified so far, are trilete and monolete spores, saccate and monocolpate grains.
DISCUSSION The present material is of a particular interest because it was found in a new geographic area where palynological data are lacking. The Lower Cretaceous material so far available for comparison occurs in Australia, North America, Europe and Asia. Patagonia belongs to the palaeogeographic unit known as Gondwana, where similar taphofloras existed during the Palaeozoic and Mesozoic eras. The palaeobotanical data based on megascopic remains are now fully confirmed by the palynological results, as far as Australia (and Antarctica) and Pata214
Rev. Palaeobotan. Palynol., I (1967) 211-21 7
Stratigraphlcal Geographical distribution
~
distribution
O
C
c
,_
c
.u_
.~
o
>
"-
~
m
>
.~ The Netherlands Great Britain Germany Australia
O
O
-r
Species
O
rn
m
<
<
DU
$estrosporites ~$eudoalveolotus
a
Canada U.S.A. Australia U.SA. Canada Great Britain Canada ~ustralia U.S.S.R. t~ustralia U.S.S.R. Canada
Rouseisporites reticulotus Taurocuspor/tes segrnentatus Trilobospor/tes apiverrucatus Trilobosporites ourverulentus
m m m
TrHobospor/t • s trioreticulosus Foraminisporis
Australia
U.SA. Australia U.S.S.R. Germany Great Britain U.S.S.R. U.S.A. Australia Tunisia Australia U.S.S.R.
dailyi
Contignisporites cooksonii "
Oenso/sporites velatus
.m
Aequitriradites splnulosus
Canada Germany
U.S.A. Australia U.S.S.R. Germany
Aequ/tr/rad/tes verrucosus
Aequitriradites boculatus Schizosporis reticulatus Clavatip.ollenites hughestt Classopoll/s torosus ~._ Microcachryidites v antarcticus
Germany Australia Canada Great Britain U.S.A. U.S.A. Great New
Britain Zealand
Australia New Zealand Australia
"
~
Trisaccites rnicrosaccaturn
Fig.1. Pollen-spore assemblage of already known species from other regions indicating their geologic range.
Cicatricosisporites hughesii, Alisporites grandis, Podocarpidites ellipticus, Trisaccites microsaccatum, Microcachryidites antarcticus, Inaperturopollenites limbatus. However, some taxa found in Patagonia are known to occur in other regions but the Gondwana: Taurocusporites segmentatus, Trilobosporites apiverrucatus, Aequitriradites baculatus, gonia are concerned. Some taxa are c o m m o n only to both areas:
Rev. Palaeobotan. Palynol., 1 (1967) 211-217
215
PLATE II
2l 6
Rev. Palaeobotan. Palynol., I (1967) 211-217
Cicatricosisporites ethmos, Concavissiml~porit~ verrucostts and Clavatipollenites hughesii. Their presence indicates that the Patagonian assemblage, although closely comparable with the Australian, has some elements in common with other palaeobotanical regions, and therefore, some relations among Patagonia and those regions, which are not known for Australia, have existed. On the other hand, a high percentage of endemic taxa indicates a defined character of the Lower Cretaceous vegetation in Patagonia. This is also confirmed by the study of megascopic taxa found in the same formation (more than seventy species, many with cuticles preserved). The spore assemblage seems to be rather cosmopolitan, many species being known from different northern and southern areas;they are usually represented by few individuals. Many species of pollen grains, which are known in other areas, are essentially of "gondwanic" affinity, specially the saccate grains. The gymnosperms are represented by fewer species than the pteridophytes (and bryophytes) but they markedly dominate the palynological spectrum. The age of the Baquer6 Formation may be deduced from Fig.1. The most useful species for stratigraphic purposes so far determined are included and their geologic range in every country (or region) is recorded. The vertical bands corresponding to the Barremian andAptian stages cross most of the horizontal lines of records (36 for the Barremian and 34 for the Aptian). It is difficult to decide the value of lowest and uppermost records of some individual taxa, in order to precise age determination. Aequitriradites baculatus, known in Germany, seems to extend only up to the end of the Barremian, but other similar records are still necessary. On the other hand, some taxa known from more than one region, seem to have appeared during the Barremian" Taurocusporites segmentatus, Trilobosporites purverulentus, T. trioreticulosus. The lowest possible age of our assemblage is thus Barremian. Some other taxa, on the other hand, extend their range up to the Albian. The absence of typical angiosperms (megascopic and microscopic material) excludes an Albian age and puts the possible top of our assemblage in the Aptian.
P L A T E II A. Inaperturopollenites sp. B. Clavatipollenites hughesii COOPER C. Ginkgocycadophytus sp. D. Monosaccate grain E. lnaperturopollenites limbatus BALME(× 700) F. Alisporites grandis (COOKSON)DETTMANN G. Microcachryidites antarcticus COOKSON H. Caytonipollenites pallidus (REISSINGER) I. Classopollis sp. ( × 700) J. Zonalapollenites trilobatus BALME Magnification x 600 (except where otherwise stated). Rev. Palaeobotan. Palynol., 1 (1967) 211-217
217