 | Texas Pennsylvanian FossilsDedicated to the Study of Pennsylvanian Fossils, Sponsored by Members of the Dallas Paleontological Society |
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Mollusca - Bivalves / Pelecypods | The Phylum Mollusca is a large and varied invertebrate group within the Animal Kingdom. They are characterized by a soft body with a strong muscular foot and usually (but not always) covered by a shell. The Bivalves are probably the most familiar Class of mollusks as the two shelled animals are found throughout the world in a variety of habitats and can be quite common as most beach goers will attest. They arose in the Early Cambrian and diversified rapidly in the Ordovician along with Brachiopods as the two major groups of marine filter feeders. While both groups suffered significant diversity reduction at the end Permian extinction event, the Bivalves were more successful in recovering during the Mesozoic. Although outwardly similar to brachiopods, bivalves have a different internal anatomy, and their shells are differentiated most easily by a difference in symmetry. Brachiopods have a plane of symmetry that bisects the two valves making left and right sides mirror images while Bivalves have their plane of symmetry between the two shells (each shell is a mirror image of the other). There are a few exceptions within the Bivalves, such as oysters, whose shells are more irregularly shaped and do not conform to the symmetry “rule”. In the Finis, bivalves are quite common and varied, like the brachiopods. Several genera are very common such as Astartella, Palaeonielo, Polidevchia, and Schizodus. Many of the bivalves are thin shelled and can be somewhat fragile and fragmentary or found as internal molds (steinkerns). ---------------------------------------------------------------------------------------------------------------------------------------- Scroll through images or click to enlarge. Fossils are grouped taxonomically in a phylogenetic order using the Treatise arrangement of Carter 2011 as a guide. Collections are from Mike DeBrock (MD), Josh Hanley (JH), Dr. Peter Holterhoff (PH), Mark McKinzie (MM), John McLeod (JM), Dr. Ben Neuman (BN), Bob Williams (BW), Sveta Earnest (SE), Dr. Tom Yancey (TY), and Rodney Wise (RW). All scales are shown in millimeters unless otherwise noted. |
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Images | Taxonomy/Stratigraphy/ | Images | Taxonomy/Stratigraphy/ |
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Kingdom: Animalia Phylum: Mollusca Class: Bivalvia Order: Nuculida Family: Nuculidae Genus: Nuculavus Species: N. croneisi Finis Shale, Graham Formation Lost Creek Dam, Jacksboro, TX Collection: BN | Kingdom: Animalia Phylum: Mollusca Class: Bivalvia Order: Nuculida Family: Nuculidae Genus: Nuculavus Species: N. triangularis Finis Shale, Graham Formation Lost Creek Dam, Jacksboro, TX Collection: MD |
Kingdom: Animalia Phylum: Mollusca Class: Bivalvia Order: Nuculida Family: Nuculidae Genus: Nuculopsis Species: N. cf. girtyi Finis Shale, Graham Formation Lost Creek Dam, Jacksboro, TX Collection: BN | Kingdom: Animalia Phylum: Mollusca Class: Bivalvia Order: Nuculida Family: Nuculidae Genus: Economolopsis Species: E. anodontoides Finis Shale, Graham Formation Lost Creek Dam, Jacksboro, TX Collection: MM, BN Note: Formerly Nuclopsis anodontoides |
Kingdom: Animalia Phylum: Mollusca Class: Bivalvia Order: Nuculanida Family: Polidevciidae Genus: Phestia Species: P. inflata Finis Shale, Graham Formation Lost Creek Dam, Jacksboro, TX Collection: | Kingdom: Animalia Phylum: Mollusca Class: Bivalvia Order: Nuculanida Family: Polidevciidae Genus: Polidevcia Species: P. arata Finis Shale, Graham Formation Lost Creek Dam, Jaksboro, TX Collection: MM |
Kingdom: Animalia Phylum: Mollusca Class: Bivalvia Order: Nuculanida Family: Polidevciidae Genus: Polidevcia Species: P. attenuata Finis Shale, Graham Formation Lost Creek Dam, Jacksboro, TX Collection: | Note: Kingdom: Animalia Phylum: Mollusca Class: Bivalvia Order: Nuculanida Family: Polidevciidae Genus: Polidevcia Species: P. bellistriata Finis Shale, Graham Formation Lost Creek Dam, Jacksboro, TX Collection: BN Note: Genus formerly known as Phestia |
Note:Kingdom: Animalia Phylum: Mollusca Class: Bivalvia Order: Nuclulanida Family: Malletidae Genus: Palaeoneilo Species: P. oweni Finis Shale, Graham Formation Lost Creek Dam, Jacksboro, TX Collection: BN Note: Includes those formerly in genus Anthraconeilo | Kingdom: Animalia Phylum: Mollusca Class: Bivalvia Order: Nuculanida Family: Sareptidae Genus: Paleyoldia Species: P. glabra Finis Shale, Graham Formation Lost Creek Dam, Jacksboro, TX Collection: BN |
Autobranchia Orders Mytilida, Arcida, Myalinida, and Ostreida |
Kingdom: Animalia Phylum: Mollusca Class: Bivalvia Subclass: Autobranchia Order: Mytilida Family: Mytilidae Genus: Volsellina Species: V. subelliptica Finis Shale, Graham Formation Lost Creek Dam, Jacksboro, TX Collection: SE | Kingdom: Animalia Phylum: Mollusca Class: Bivalvia Subclass: Autobranchia Order: Arcida Family: Parallelodontidae Genus: Parallelodon Species: P. carbonarius Finis Shale, Graham Formation Lost Creek Dam, Jacksboro, TX Collection: MD |
Kingdom: Animalia Phylum: Mollusca Class: Bivalvia Subclass: Autobranchia Order: Myalinida Family: Myalinidae Genus: Orthomyalina Species: O. slocomi Finis Shale, Graham Formation Lost Creek Dam, Jacksboro, TX Collection: BN | Kingdom: Animalia Phylum: Mollusca Class: Bivalvia Subclass: Autobranchia Order: Myalinida Family: Myalinidae Genus: Orthomyalina Species: O. subquadrata Finis Shale, Graham Formation Lost Creek Dam, Jacksboro, TX Collection: MM |
Kingdom: Animalia Phylum: Mollusca Class: Bivalve Subclass: Autobranchia Order: Ostreida Family: Monopteriidae Genus: Monoptera Species: M. magna Finis Shale, Graham Formation Lost Creek Dam, Jacksboro, TX Collection: BN | Kingdom: Animalia Phylum: Mollusca Class: Bivalvia Subclass: Autobranchia Order: Ostreida Family: Myalinidae Genus: "Anthracoptera" Species: "A". polita Finis Shale, Graham Formation Lost Creek Dam, Jacksboro, TX Collection: BN |
Kingdom: Animalia Phylum: Mollusca Class: Bivalvia Subclass: Autobranchia Order: Ostreida Family: Pinnidae Genus: Falcatopinna Species: F. bobwilliamsi Finis Shale, Graham Formation Lost Creek Dam, Jacksboro, TX Collection: TY | Kingdom: Animalia Phylum: Mollusca Class: Bivalvia Subclass: Autobranchia Order: Ostreida Family: Pinnidae Genus: Girtopinna Species: G. jimflisi Finis Shale, Graham Formation Lost Creek Dam, Jacksboro, TX Collection: TY |
Kingdom: Animalia Phylum: Mollusca Class: Bivalve Subclass: Autobranchia Order: Ostreida Family: Pinnidae Genus: Meekopinna Species: M. americana Finis Shale, Graham Formation Lost Creek Dam, Jacksboro, TX Collection: | Kingdom: Animalia Phylum: Mollusca Class: Bivalve Subclass: Autobranchia Order: Ostreida Family: Pinnidae Genus: Meekopinna Species: M. nebrascensis Finis Shale, Graham Formation Lost Creek Dam, Jacksboro, TX Collection: BW |
Kingdom: Animalia Phylum: Mollusca Class: Bivalvia Subclass: Autobranchia Order: Ostreida Family: Pterineidae Genus: Willipteria Species: W. nestelli Finis Shale, Graham Formation Lost Creek Dam, Jacksboro, TX Collection: TY, MM |
Autobranchia Order Pectinida |
Kingdom: Animalia Phylum: Mollusca Class: Bivalvia Order: Pectinida Family: Aviculopectinidae Genus: Aviculopecten Species: A. arctisulcatus Finis Shale, Graham Formation Lost Creek Dam, Jacksboro, TX Collection: | Kingdom: Animalia Phylum: Mollusca Class: Bivalvia Order: Pectinida Family: Aviculopectinidae Genus: Aviculopecten Species: A. moorei Finis Shale, Graham Formation Lost Creek Dam, Jacksboro, TX |
Kingdom: Animalia Phylum: Mollusca Class: Bivalvia Order: Pectinida Family: Limipectinidae Genus: Limipecten Species: L. texanus Finis Shale, Graham Formation Lost Creek Dam, Jacksboro, TX Collection: SE, BN | Kingdom: Animalia Phylum: Mollusca Class: Bivalvia Order: Pectinida Family: Limipectinidae Genus: Acanthopecten Species: A. meeki Finis Shale, Graham Formation Lost Creek Dam, Jacksboro, TX Collection: MM, SE |
Kingdom: Animalia Phylum: Mollusca Class: Bivalvia Order: Pectinida Family: Aviculopectinidae Genus: Clavicosta Species: C. n. sp. Finis Shale, Graham Formation Lost Creek Dam, Jacksboro, TX Collection: SE, BN | Kingdom: Animalia Phylum: Mollusca Class: Bivalvia Order: Pectinida Family: Aviculopectinidae Genus: Fasciculiconcha Species: F. sp. Finis Shale, Graham Formation Lost Creek Dam, Jacksboro, TX Collection: MM |
Kingdom: Animalia Phylum: Mollusca Class: Bivalvia Order: Pectinida Family: Heteropectinidae Genus: Girtypecten Species: G. sp. Finis Shale, Graham Formation Lost Creek Dam, Jacksboro, TX Collection: | Kingdom: Animalia Phylum: Mollusca Class: Bivalvia Order: Pectinida Family: Streblochondriidae Genus: Streblochondria Species: S. sculptillis Finis Shale, Graham Formation Lost Creek Dam, Jacksboro, TX Collection: RW, BN, MD |
Kingdom: Animalia Phylum: Mollusca Class: Bivalvia Order: Pectinida Family: Pseudomonotidae Genus: Pseudomonotis Species: P. robusta Finis Shale, Graham Formation Lost Creek Dam, Jacksboro, TX Collection: BN | Kingdom: Animalia Phylum: Mollusca Class: Bivalvia Order: Pectinida Family: Pseudomonotidae Genus: Pseudomonotis Species: P. hawni Finis Shale, Graham Formation Lost Creek Dam, Jacksboro, TX Collection: BN |
Heteroconchia Orders Trigoniida, Carditida, and Pholadomyida |
Kingdom: Animalia Phylum: Mollusca Class: Bivalvia Order: Trigoniida Family: Schizodidae Genus: Schizodus Species: S. cf. alpinus Finis Shale, Graham Formation Lost Creek Dam, Jacksboro, TX Collection: BN | Kingdom: Animalia Phylum: Mollusca Class: Bivalvia Order: Trigoniida Family: Schizodidae Genus: Schizodus Species: S. ulrichi Finis Shale, Graham Formation Lost Creek Dam, Jacksboro, TX Collection: BN, MM |
Kingdom: Animalia Phylum: Mollusca Class: Bivalvia Order: Trigoniida Family: Uncertain Genus: Sedgwickia Species: S. sp. Finis Shale, Graham Formation Lost Creek Dam, Jacksboro, TX Collection: SE, BN | Kingdom: Animalia Phylum: Mollusca Class: Bivalvia Order: Carditida Family: Astartidae Genus: Astartella Species: A. compacta Finis Shale, Graham Formation Lost Creek Dam, Jacksboro, TX Collection: MD, BN |
Kingdom: Animalia Phylum: Mollusca Class: Bivalvia Order: Carditida Family: Astartidae Genus: Astartella Species: A. concentrica Finis Shale, Graham Formation Lost Creek Dam, Jacksboro, TX Collection: MM, BN | Kingdom: Animalia Phylum: Mollusca Class: Bivalvia Order: Carditida Family: Astartidae Genus: Astartella Species: A. varica Finis Shale, Graham Formation Lost Creek Dam, Jacksboro, TX Collection: MD, BN, MM |
Kingdom: Animalia Phylum: Mollusca Class: Bivalvia Order: Hiatellida Family: Edmondiidae Genus: Edmondia Species: E. ovata Finis Shale, Graham Formation Lost Creek Dam, Jacksboro, TX Collection: JH | Kingdom: Animalia Phylum: Mollusca Class: Bivalvia Order: Cardiida Family: Grammysiidae Genus: Ectogrammysia Species: E. sp. Finis Shale, Graham Formation Lost Creek Dam, Jacksboro, TX Collection: SE JH Note: Also published under the name Myofossa sp. |
Kingdom: Animalia Phylum: Mollusca Class: Bivalvia Order: Cardiida Family: Sanguinolitidae Genus: Wilkingia Species: W. terminale Finis Shale, Graham Formation Lost Creek Dam, Jacksboro, TX Collection: MM | Kingdom: Animalia Phylum: Mollusca Class: Bivalvia Order: Cardiida Family: Kalenteridae Genus: Pleurophorella Species: P. costata Finis Shale, Graham Formation Lost Creek Dam, Jacksboro, TX Collection: BW, BN |
Kingdom: Animalia Phylum: Mollusca Class: Bivalvia Order: Cardiida Family: Sanguinolitidae Genus: Praeundulomya Species: P. maxima Finis Shale, Graham Formation Lost Creek Dam, Jacksboro, TX Collection: MM, British Museum |
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