- Email: [email protected]
Coelomycetes in Dominican and Mexican amber
Mycol. Res. 107 (1): 117–122 (January 2003). f The British Mycological Society
117
DOI: 10.1017/S0953756202007001 Printed in the United Kingdom.
Coelomycetes in Dominican and Mexican amber
George POINAR Jr Department of Entomology, Oregon State University, Corvallis, Oregon 97331, USA. E-mail : [email protected] Received 22 December 2001; accepted 12 September 2002.
Three species of fossil epiphyllous coelomycetes are described from Dominican and Mexican amber in the new genera, Asteromites gen. nov., Leptostromites gen. nov. and Leptothyrites gen. nov. Characters of the pycnidia and spores most closely resemble members of their extant respective genera, Leptostroma, Asteromella, and Leptothyrium, respectively. A. mexicanus sp. nov. occurs on a petal (possibly from a caesalpinoid legume such as Peltogyne) in Mexican amber. Leptostromites ellipticus sp. nov. occurs on a dicot leaf in Dominican amber, and Leptothyrites dominicanus sp. nov. on a monocot (grass ?) leaf in Dominican amber.
INTRODUCTION While spores and fruit bodies can be used to establish various fungal groups dating back to the Paleozoic (Pirozynski 1976, Poinar & Milki 2001), fossil epiphyllous fungi with pycnidia are rare (Tiffney & Barghoorn 1974, Taylor & Taylor 1993). During the past 25 years, I have searched for epiphyllous fungi in amber, supposing that there should be a wide range of fungi growing on leaves that fell into resin deposits. While leaf spots are quite common today, pycnidial fungi are rare in amber deposits (Poinar 1992). Some hyphomycetous epiphyllous forms have, however, been described from Baltic amber (Caspary & Klebs 1907). Three pieces of amber were found to contain coelomycetes on leaves and a petal, in Dominican and Mexican amber respectively. Both Dominican and Mexican amber have revealed some interesting fungal remains. These include a gilled mushroom (Poinar & Singer 1990), entomogenous fungi (Poinar & Thomas 1982, 1984) and conidial and mycelial stages (Stubblefield et al. 1985, Rikkinen & Poinar 2001) in Dominican amber, and puffballs in Mexican amber (Poinar 2001). The Dominican specimens reported on in this study were obtained from mines in the Cordillera Septentrional of the Dominican Republic which occur at 19x 30k– 20x 00k N, 70x 30k–71x 00k E. This amber is considered to have been formed by the extinct leguminous tree, Hymenaea protera (Poinar 1991). Dating of Dominican amber is controversial, with age estimates ranging from 20 to 15 Myr based on foraminifera (Iturralde-Vincent & MacPhee 1996) to 45–30 Myr based on coccoliths
(Schlee 1990). A range of ages for Dominican amber may be likely since the amber fossils are associated with turbiditic sandstones of the Upper Eocene to Lower Miocene Mamey Group (Draper et al. 1994). The Mexican amber piece was obtained from a mine in the Simojovel area of Chiapas, Mexico located at approximately 17x 00k N, 92x 30k E. Amber in this region occurs in lignitic beds among sequences of primarily marine calcareous sandstones and silt. The amber occurs in association with the Balumtun Sandstone of the early Miocene and the La Quinta formation of the Late Oligocene. These formations have been assigned radiometric ages from 22.5 to 26 Myr (Berggren & van Couvering 1974). The locations of the various amber mines in Mexico and the Dominican Republic are detailed in Poinar (1992). Both Dominican and Mexican amber is secondarily deposited in sedimentary rocks, which makes a definite age determination difficult (Poinar & Mastalerz 2000).
MATERIALS AND METHODS The amber pieces were polished to remove as much amber as possible from around the specimens. One Dominican specimen (AF-9-26) revealed a number of elliptical-shaped pycnidia on the surface of a dicot leaf. The piece of amber measured 26 mm max. length, 5 mm max. width, 2 mm thick and weighed 0.2 g. The second Dominican specimen (AF-9-25) consisted of several pycnidia on the leaf of a monocot (probably a grass leaf since at least three grass genera have been reported from
Coelomycetes in amber
118
1
2
3
Figs 1–3. Asteromites mexicanus (Sy-1-116A). Fig. 1. Pycnidium (arrow) on flower petal. Bar=860 mm. Fig. 2. Pycnidium with top portion broken away exposing inner conidiophores and conidia. Bar=80 mm. Fig. 3. Conidia (arrows) inside pycnidium. Bar=15 mm.
these deposits (Poinar & Poinar 1999). The piece measured 15 mm max. length, 5 mm max. width, 1 mm thick and weighed 0.1 g. The Mexican amber specimen (Sy-1-116) consisted of several pycnidia on two petals of what appeared to be a legume (similar to the petals of Peltogyne as found in Dominican amber ; see Poinar & Poinar 1999). The piece was cut in half, retaining one petal in each piece. The piece with a single large and two smaller pycnidia (Sy-1-116A) measured 13 mm
max. length, 9 mm max. width, 3 mm thick and weighed 0.2 g. The piece with three large pycnidia (Sy-1-116B) measured 14 mm max. length, 10 mm max. width, 3 mm thick and weighed 0.3 g. Observations and photographs were made under r20 and r40 objectives (with a maximum of r625 magnification) with a Nikon Optiphot microscope. All specimens are in the Poinar amber collection maintained at Oregon State University.
G. Poinar Jr
119
4
5
6
7
Figs 4 –7. Leptostromites ellipticus (AF-9-26) in Dominican amber. Fig. 4. Pycnidia on dicot leaf under incident light. Bar=1.1 mm. Fig. 5. Pycnidium under transmitted light. Bar=51 mm. Fig. 6. Edge of an opened pycnidium showing conidia (arrows) and conidiophores. Bar=33 mm. Fig. 7. Tip of pycnidia showing conidiophores and conidia (arrows). Bar=33 mm.
Coelomycetes in amber
8
10
120
9
11
Figs 8–11. Leptothyrites dominicanus (AF-9-25). Fig. 8. Pycnidia (n=5) on the surface of a monocot leaf in Dominican amber. Bar=1.2 mm. Fig. 9. Pycnidium showing fragmentation. Bar=90 mm. Fig. 10. Pycnidium showing radiating top similar to some present members of the genus Leptothyrium. Bar=90 mm. Fig. 11. Opening in one of the pycnidia showing conidiophores and conidia (arrows). Bar=40 mm.
G. Poinar Jr
121
RESULTS
minute, round to slightly elliptical, hyaline, and single celled spores. The generic names are based on extant genera that superficially resemble the fossils in respect to pycnidia shape and type of aperature, and spore shape and character. Asteromella is characterized by dark, globose, ostiolate pycnidia amidst radiating dark hyphae and 1-celled, hyaline ovoid to cylindrical conidia. Modern Asteromella species occur on dicots, including the caesalpinoid, Parkinsonia (Farr et al. 1989). Leptostroma is characterized by separate, subsuperficial, flattened to elongate black pycnidia that are more or less cleft lengthwise and simple, 1-celled, hyaline conidia. Extant species of Leptostroma occur on ferns, gymnosperms, dicots and monocots (Farr et al. 1989). Leptothyrium has shield-shaped, dark, superficial or erumpent pycnidia with or without an ostiole and 1-celled, hyaline, ovoid to oblong conidia. Recent Leptothyrium have been reported on ferns, gymnosperms, dicots and monocots (including grasses) (Farr et al. 1989). Several grasses, including Arthrostylidium, Panicum and Pharus have been reported from Dominican amber (Poinar & Poinar 1999). One of the features noted in all of the fossil species was the small size of the spores, which are smaller than most of the described species in the above extant genera. Since they are relatively thin-walled, it is possible that some shrinkage occurred in the resin, thus giving smaller than actual values. An oribatid mite was on the leaf containing L. dominicanus, presumably feeding on fungal remains. Oribatid mites are common inhabitants of leaf surfaces and have been previously reported in Dominican amber (Norton & Poinar 1993). Finding pycnidia on a petal is interesting since the petal shows no sign of decay, suggesting that the fungus might have been parasitic. The other two specimens were on older leaves and could have been saprophytic.
These fossils are placed in form genera, as recommended for descriptions of fossil fungi (Pirozynski & Weresub 1984). Only English descriptions are used to validate the new taxa as these are fossil fungi (Art. 36.1). Asteromites Poinar, gen. nov. Pycnidia superficial, separate, circular, dark, irregular opening on top ; conidia ovoid, hyaline, 1-celled. Type: A. mexicanus. Asteromites mexicanus Poinar, sp. nov.
(Figs 1–3)
Pycnidia complete, 99–340 mm diam ; conidia minute, 3– 4r1–3 mm. Holotype : Mexico : Chiapas, located at approximately 17x 00k N, 92x 30k W, amber mine, on a petal (possibly from a caesalpinoid legume such as Peltogyne). Specimen SY-1-116A (Poinar amber collection at Oregon State University). Leptostromites Poinar, gen. nov. Pycnidia subsuperficial, separate, flattened, elongate ovoid, only upper portion well developed ; light tan in incident light ; dark in transmitted light ; mostly opening by a cleft, sometimes by irregular fractures. Type: L. ellipticus. Leptostromites ellipticus Poinar, sp. nov.
(Figs 4–7)
Pycnidia 117–333 mm in length and 32–89 mm in greatest width. Conidia small, hyaline, elliptical, 2–5r1–3 mm wide. Holotype : Dominican Republic : 19x 30k–20x 00k N, 70x 30k–71x 00k W, Amber mine, on a dicotyledonous leaf. Specimen AF-9-26 (Poinar amber collection at Oregon State University). Leptothyrites Poinar, gen. nov.
ACKNOWLEDGEMENTS
Pycnidia superficial, shield-shaped, without ostiole, opening by fragmentation. Conidia minute, hyaline, 1 celled, round to ovoid. Type: L. dominicanus.
Thanks are extended to Jeffrey Stone for helpful discussions, and to Roberta Poinar for comments on earlier drafts of this manuscript.
Leptothyrites dominicanus Poinar, sp. nov. (Figs 8–11)
Berggren, W. A. & Van Couvering, J. A. H. (1974) The late Neogene. Palaeogeography, Palaeoclimatology & Palaeoecology 16: 1–216. Caspary, R. & Klebs, R. (1907) Die Flora des Bernsteins und anderer fossiler Harze des ostpreufsischen Tertia¨rs. Vol. 1. Ko¨niglich Preussischen Landesanstalt, Berlin. Draper, G., Mann, P. & Lewis, J. F. (1994) Hispaniola. In Caribbean Geology: an introduction (S. Donovan & T. A. Jackson, eds): 129–150. University of the West Indies Publishers’ Association, Kingston, Jamaica. Farr, D. F., Bills, G. F., Chamuris, G. P. & Rossman, A. Y. (1989) Fungi on Plants and Plant Products in the United States. American Phytopathological Society Press, St Paul, MN. Iturralde-Vincent, M. A. & MacPhee, R. D. E. (1996) Age and paleogeographic origin of Dominican amber. Science 273 : 1850–1852. Norton, R. A. & Poinar jr, G. O. (1993) Reassessment and new records of oribatic mite fossils from Tertiary neotropical amber. Acarologia 34: 57–68.
Pycnidia incomplete, with only the upper portion well developed ; pycnidia 283–385 mm diam. Conidia hyaline to tan, 5–7r3–4 mm wide. Holotype : Dominican Republic : 19x 30k–20x 00k N, 70x 30k–71x 00k W, Amber mine, on a monocotyledanous (possibly grass) leaf. Specimen AF-9-25 (Poinar amber collection at Oregon State University).
DISCUSSION All of the specimens revealed characters typical of extant coelomycetes : conidiophores arranged in pycnidia and
REFERENCES
Coelomycetes in amber Pirozynski, K. A. (1976) Fungal spores in the fossil record. Biological Memoirs Palaeopalynology Series 4, 1: 104 –120. Pirozynski, K. A. & Weresub, L. K. (1984) The classification and nomenclature of fossil fungi. In The Whole Fungus (B. Kendrick, ed.) 2: 653–688. National Museum of Natural Sciences, Ottawa. Poinar jr, G. O. (1991) Hymenaea protera sp. n. from Dominican amber has African affinities. Experientia 47: 1075–1082. Poinar jr, G. O. (1992) Life in Amber. Stanford University Press, Stanford. Poinar jr, G. O. (2001) Fossil puffballs (Gasteromycetes: Lycoperdales) in Mexican amber. Historical Biology 15: 119–122. Poinar jr, G. O. & Thomas, G. M. (1982) An entomophthoralen fungus from Dominican amber. Mycologia 74: 332–334. Poinar jr, G. O. & Thomas, G. M. (1984) A fossil entomogenous fungus from Dominican amber. Experientia 40: 578–579. Poinar jr, G. O. & Singer, R. (1990) Upper Eocene gilled mushroom from the Dominican Republic. Science 248 : 1099–1101. Poinar jr, G. O. & Poinar, R. (1999) The Amber Forest. Princeton University Press, Princeton.
122 Poinar jr, G. O. & Mastalerz, M. (2000) Taphonomy of fossilized resins: determining the biostratinomy of amber. Acta Geologica Hispanica 35: 171–182. Poinar jr, G. O. & Milki, R. (2001) Lebanese Amber. Oregon State University Press, Corvallis. Rikkinen, J. & Poinar jr, G. O. (2001) Fossilized fungal mycelium from Tertiary Dominican amber. Mycological Research 105: 890–896. Schlee, D. (1990) Das Bernstein-Kabinett. Stuttgart Beitra¨ge fu¨r Naturkunde, C 28: 1–100. Stubblefield, S. P., Miller, C. E., Taylor, T. N. & Cole, G. T. (1985) Geotrichites glaesarius, a conidial fungus from Tertiary Dominican amber. Mycologia 77: 11–16. Taylor, T. N. & Taylor, E. L. (1993) The Biology and Evolution of Fossil Plants. Prentice Hall, Englewood Cliffs. Tiffney, B. H. & Barghoorn, E. S. (1974) The fossil record of the fungi. Occasional Papers of the Farlow Herbarium of Cryptogamic Botany 7: 1– 42. Corresponding Editor: R. S. Currah
117
DOI: 10.1017/S0953756202007001 Printed in the United Kingdom.
Coelomycetes in Dominican and Mexican amber
George POINAR Jr Department of Entomology, Oregon State University, Corvallis, Oregon 97331, USA. E-mail : [email protected] Received 22 December 2001; accepted 12 September 2002.
Three species of fossil epiphyllous coelomycetes are described from Dominican and Mexican amber in the new genera, Asteromites gen. nov., Leptostromites gen. nov. and Leptothyrites gen. nov. Characters of the pycnidia and spores most closely resemble members of their extant respective genera, Leptostroma, Asteromella, and Leptothyrium, respectively. A. mexicanus sp. nov. occurs on a petal (possibly from a caesalpinoid legume such as Peltogyne) in Mexican amber. Leptostromites ellipticus sp. nov. occurs on a dicot leaf in Dominican amber, and Leptothyrites dominicanus sp. nov. on a monocot (grass ?) leaf in Dominican amber.
INTRODUCTION While spores and fruit bodies can be used to establish various fungal groups dating back to the Paleozoic (Pirozynski 1976, Poinar & Milki 2001), fossil epiphyllous fungi with pycnidia are rare (Tiffney & Barghoorn 1974, Taylor & Taylor 1993). During the past 25 years, I have searched for epiphyllous fungi in amber, supposing that there should be a wide range of fungi growing on leaves that fell into resin deposits. While leaf spots are quite common today, pycnidial fungi are rare in amber deposits (Poinar 1992). Some hyphomycetous epiphyllous forms have, however, been described from Baltic amber (Caspary & Klebs 1907). Three pieces of amber were found to contain coelomycetes on leaves and a petal, in Dominican and Mexican amber respectively. Both Dominican and Mexican amber have revealed some interesting fungal remains. These include a gilled mushroom (Poinar & Singer 1990), entomogenous fungi (Poinar & Thomas 1982, 1984) and conidial and mycelial stages (Stubblefield et al. 1985, Rikkinen & Poinar 2001) in Dominican amber, and puffballs in Mexican amber (Poinar 2001). The Dominican specimens reported on in this study were obtained from mines in the Cordillera Septentrional of the Dominican Republic which occur at 19x 30k– 20x 00k N, 70x 30k–71x 00k E. This amber is considered to have been formed by the extinct leguminous tree, Hymenaea protera (Poinar 1991). Dating of Dominican amber is controversial, with age estimates ranging from 20 to 15 Myr based on foraminifera (Iturralde-Vincent & MacPhee 1996) to 45–30 Myr based on coccoliths
(Schlee 1990). A range of ages for Dominican amber may be likely since the amber fossils are associated with turbiditic sandstones of the Upper Eocene to Lower Miocene Mamey Group (Draper et al. 1994). The Mexican amber piece was obtained from a mine in the Simojovel area of Chiapas, Mexico located at approximately 17x 00k N, 92x 30k E. Amber in this region occurs in lignitic beds among sequences of primarily marine calcareous sandstones and silt. The amber occurs in association with the Balumtun Sandstone of the early Miocene and the La Quinta formation of the Late Oligocene. These formations have been assigned radiometric ages from 22.5 to 26 Myr (Berggren & van Couvering 1974). The locations of the various amber mines in Mexico and the Dominican Republic are detailed in Poinar (1992). Both Dominican and Mexican amber is secondarily deposited in sedimentary rocks, which makes a definite age determination difficult (Poinar & Mastalerz 2000).
MATERIALS AND METHODS The amber pieces were polished to remove as much amber as possible from around the specimens. One Dominican specimen (AF-9-26) revealed a number of elliptical-shaped pycnidia on the surface of a dicot leaf. The piece of amber measured 26 mm max. length, 5 mm max. width, 2 mm thick and weighed 0.2 g. The second Dominican specimen (AF-9-25) consisted of several pycnidia on the leaf of a monocot (probably a grass leaf since at least three grass genera have been reported from
Coelomycetes in amber
118
1
2
3
Figs 1–3. Asteromites mexicanus (Sy-1-116A). Fig. 1. Pycnidium (arrow) on flower petal. Bar=860 mm. Fig. 2. Pycnidium with top portion broken away exposing inner conidiophores and conidia. Bar=80 mm. Fig. 3. Conidia (arrows) inside pycnidium. Bar=15 mm.
these deposits (Poinar & Poinar 1999). The piece measured 15 mm max. length, 5 mm max. width, 1 mm thick and weighed 0.1 g. The Mexican amber specimen (Sy-1-116) consisted of several pycnidia on two petals of what appeared to be a legume (similar to the petals of Peltogyne as found in Dominican amber ; see Poinar & Poinar 1999). The piece was cut in half, retaining one petal in each piece. The piece with a single large and two smaller pycnidia (Sy-1-116A) measured 13 mm
max. length, 9 mm max. width, 3 mm thick and weighed 0.2 g. The piece with three large pycnidia (Sy-1-116B) measured 14 mm max. length, 10 mm max. width, 3 mm thick and weighed 0.3 g. Observations and photographs were made under r20 and r40 objectives (with a maximum of r625 magnification) with a Nikon Optiphot microscope. All specimens are in the Poinar amber collection maintained at Oregon State University.
G. Poinar Jr
119
4
5
6
7
Figs 4 –7. Leptostromites ellipticus (AF-9-26) in Dominican amber. Fig. 4. Pycnidia on dicot leaf under incident light. Bar=1.1 mm. Fig. 5. Pycnidium under transmitted light. Bar=51 mm. Fig. 6. Edge of an opened pycnidium showing conidia (arrows) and conidiophores. Bar=33 mm. Fig. 7. Tip of pycnidia showing conidiophores and conidia (arrows). Bar=33 mm.
Coelomycetes in amber
8
10
120
9
11
Figs 8–11. Leptothyrites dominicanus (AF-9-25). Fig. 8. Pycnidia (n=5) on the surface of a monocot leaf in Dominican amber. Bar=1.2 mm. Fig. 9. Pycnidium showing fragmentation. Bar=90 mm. Fig. 10. Pycnidium showing radiating top similar to some present members of the genus Leptothyrium. Bar=90 mm. Fig. 11. Opening in one of the pycnidia showing conidiophores and conidia (arrows). Bar=40 mm.
G. Poinar Jr
121
RESULTS
minute, round to slightly elliptical, hyaline, and single celled spores. The generic names are based on extant genera that superficially resemble the fossils in respect to pycnidia shape and type of aperature, and spore shape and character. Asteromella is characterized by dark, globose, ostiolate pycnidia amidst radiating dark hyphae and 1-celled, hyaline ovoid to cylindrical conidia. Modern Asteromella species occur on dicots, including the caesalpinoid, Parkinsonia (Farr et al. 1989). Leptostroma is characterized by separate, subsuperficial, flattened to elongate black pycnidia that are more or less cleft lengthwise and simple, 1-celled, hyaline conidia. Extant species of Leptostroma occur on ferns, gymnosperms, dicots and monocots (Farr et al. 1989). Leptothyrium has shield-shaped, dark, superficial or erumpent pycnidia with or without an ostiole and 1-celled, hyaline, ovoid to oblong conidia. Recent Leptothyrium have been reported on ferns, gymnosperms, dicots and monocots (including grasses) (Farr et al. 1989). Several grasses, including Arthrostylidium, Panicum and Pharus have been reported from Dominican amber (Poinar & Poinar 1999). One of the features noted in all of the fossil species was the small size of the spores, which are smaller than most of the described species in the above extant genera. Since they are relatively thin-walled, it is possible that some shrinkage occurred in the resin, thus giving smaller than actual values. An oribatid mite was on the leaf containing L. dominicanus, presumably feeding on fungal remains. Oribatid mites are common inhabitants of leaf surfaces and have been previously reported in Dominican amber (Norton & Poinar 1993). Finding pycnidia on a petal is interesting since the petal shows no sign of decay, suggesting that the fungus might have been parasitic. The other two specimens were on older leaves and could have been saprophytic.
These fossils are placed in form genera, as recommended for descriptions of fossil fungi (Pirozynski & Weresub 1984). Only English descriptions are used to validate the new taxa as these are fossil fungi (Art. 36.1). Asteromites Poinar, gen. nov. Pycnidia superficial, separate, circular, dark, irregular opening on top ; conidia ovoid, hyaline, 1-celled. Type: A. mexicanus. Asteromites mexicanus Poinar, sp. nov.
(Figs 1–3)
Pycnidia complete, 99–340 mm diam ; conidia minute, 3– 4r1–3 mm. Holotype : Mexico : Chiapas, located at approximately 17x 00k N, 92x 30k W, amber mine, on a petal (possibly from a caesalpinoid legume such as Peltogyne). Specimen SY-1-116A (Poinar amber collection at Oregon State University). Leptostromites Poinar, gen. nov. Pycnidia subsuperficial, separate, flattened, elongate ovoid, only upper portion well developed ; light tan in incident light ; dark in transmitted light ; mostly opening by a cleft, sometimes by irregular fractures. Type: L. ellipticus. Leptostromites ellipticus Poinar, sp. nov.
(Figs 4–7)
Pycnidia 117–333 mm in length and 32–89 mm in greatest width. Conidia small, hyaline, elliptical, 2–5r1–3 mm wide. Holotype : Dominican Republic : 19x 30k–20x 00k N, 70x 30k–71x 00k W, Amber mine, on a dicotyledonous leaf. Specimen AF-9-26 (Poinar amber collection at Oregon State University). Leptothyrites Poinar, gen. nov.
ACKNOWLEDGEMENTS
Pycnidia superficial, shield-shaped, without ostiole, opening by fragmentation. Conidia minute, hyaline, 1 celled, round to ovoid. Type: L. dominicanus.
Thanks are extended to Jeffrey Stone for helpful discussions, and to Roberta Poinar for comments on earlier drafts of this manuscript.
Leptothyrites dominicanus Poinar, sp. nov. (Figs 8–11)
Berggren, W. A. & Van Couvering, J. A. H. (1974) The late Neogene. Palaeogeography, Palaeoclimatology & Palaeoecology 16: 1–216. Caspary, R. & Klebs, R. (1907) Die Flora des Bernsteins und anderer fossiler Harze des ostpreufsischen Tertia¨rs. Vol. 1. Ko¨niglich Preussischen Landesanstalt, Berlin. Draper, G., Mann, P. & Lewis, J. F. (1994) Hispaniola. In Caribbean Geology: an introduction (S. Donovan & T. A. Jackson, eds): 129–150. University of the West Indies Publishers’ Association, Kingston, Jamaica. Farr, D. F., Bills, G. F., Chamuris, G. P. & Rossman, A. Y. (1989) Fungi on Plants and Plant Products in the United States. American Phytopathological Society Press, St Paul, MN. Iturralde-Vincent, M. A. & MacPhee, R. D. E. (1996) Age and paleogeographic origin of Dominican amber. Science 273 : 1850–1852. Norton, R. A. & Poinar jr, G. O. (1993) Reassessment and new records of oribatic mite fossils from Tertiary neotropical amber. Acarologia 34: 57–68.
Pycnidia incomplete, with only the upper portion well developed ; pycnidia 283–385 mm diam. Conidia hyaline to tan, 5–7r3–4 mm wide. Holotype : Dominican Republic : 19x 30k–20x 00k N, 70x 30k–71x 00k W, Amber mine, on a monocotyledanous (possibly grass) leaf. Specimen AF-9-25 (Poinar amber collection at Oregon State University).
DISCUSSION All of the specimens revealed characters typical of extant coelomycetes : conidiophores arranged in pycnidia and
REFERENCES
Coelomycetes in amber Pirozynski, K. A. (1976) Fungal spores in the fossil record. Biological Memoirs Palaeopalynology Series 4, 1: 104 –120. Pirozynski, K. A. & Weresub, L. K. (1984) The classification and nomenclature of fossil fungi. In The Whole Fungus (B. Kendrick, ed.) 2: 653–688. National Museum of Natural Sciences, Ottawa. Poinar jr, G. O. (1991) Hymenaea protera sp. n. from Dominican amber has African affinities. Experientia 47: 1075–1082. Poinar jr, G. O. (1992) Life in Amber. Stanford University Press, Stanford. Poinar jr, G. O. (2001) Fossil puffballs (Gasteromycetes: Lycoperdales) in Mexican amber. Historical Biology 15: 119–122. Poinar jr, G. O. & Thomas, G. M. (1982) An entomophthoralen fungus from Dominican amber. Mycologia 74: 332–334. Poinar jr, G. O. & Thomas, G. M. (1984) A fossil entomogenous fungus from Dominican amber. Experientia 40: 578–579. Poinar jr, G. O. & Singer, R. (1990) Upper Eocene gilled mushroom from the Dominican Republic. Science 248 : 1099–1101. Poinar jr, G. O. & Poinar, R. (1999) The Amber Forest. Princeton University Press, Princeton.
122 Poinar jr, G. O. & Mastalerz, M. (2000) Taphonomy of fossilized resins: determining the biostratinomy of amber. Acta Geologica Hispanica 35: 171–182. Poinar jr, G. O. & Milki, R. (2001) Lebanese Amber. Oregon State University Press, Corvallis. Rikkinen, J. & Poinar jr, G. O. (2001) Fossilized fungal mycelium from Tertiary Dominican amber. Mycological Research 105: 890–896. Schlee, D. (1990) Das Bernstein-Kabinett. Stuttgart Beitra¨ge fu¨r Naturkunde, C 28: 1–100. Stubblefield, S. P., Miller, C. E., Taylor, T. N. & Cole, G. T. (1985) Geotrichites glaesarius, a conidial fungus from Tertiary Dominican amber. Mycologia 77: 11–16. Taylor, T. N. & Taylor, E. L. (1993) The Biology and Evolution of Fossil Plants. Prentice Hall, Englewood Cliffs. Tiffney, B. H. & Barghoorn, E. S. (1974) The fossil record of the fungi. Occasional Papers of the Farlow Herbarium of Cryptogamic Botany 7: 1– 42. Corresponding Editor: R. S. Currah