Category: Bivalvia

Belongs within: Pterioida. Inoceramus is a diverse genus of pteriomorph molluscs known from the Jurassic and Cretaceous periods. Some reached gigantic sizes, close to two metres in length. Characters (Cox et al. 1969): Subequivalve to strongly inequivalve, ovate, trapeziform or suborbicular; posterior wing variably developed; ligamental area concave transversely; radial ornament rarely present; outer ostracum… Continue reading Inoceramus

Belongs within: Pteriomorphia.Contains: Ambonychioidea, Inoceramus, Platyceramus, Mytiloides, Pterineidae, Pinnidae, Pterioidea, Ostreoidea, Plicatuloidea. The Pterioida are a clade of three major lineages of living bivalves, the Pinnidae, Pterioidea and Ostreina, supported as a monophylum by molecular analyses (Giribet & Wheeler 2002). Members of the clade tend to have elongate shells, equivalve in Pinnidae but inaequivalve in… Continue reading Pterioida

Belongs within: Bivalvia.Contains: Praecardioida, Chaenocardiidae, Lithodomus, Aviculidae, Daonella, Halobia, Condylocardiidae, Cardiniidae, Carditidae, Astartidae, Crassatellidae, Mytilidae, Nuculanoidea, Pectinida, Pterioida, Cyrtodontidae, Limopsoidea, Arcidae, Parallelodon. The Pteriomorphia are an ecologically diverse subdivision of bivalves including such forms as scallops, oysters and mussels. Recent molecular analysis has supported a broad definition of the clade including the clades Nuculanoidea and Carditoida as… Continue reading Pteriomorphia

Belongs within: Pterioida.Contains: Pteria, Isognomonidae. The Pterioidea are a group of byssally-attached bivalves with unequal valves, the left valve generally being distinctly more inflated than the right (Cox et al. 1969). Members of the Pteriidae, the feather oysters, usually have a characteristic triangular projection on either side of the straight hinge-line. The pearl oysters of… Continue reading Pterioidea

Belongs within: Pterioida.Contains: Ostreinae. The Ostreoidea, oysters, are a group of typically cemented bivalves lacking an anterior adductor muscle and possessing a largely calcitic, foliated shell (Carter 2004). <==Ostreoidea [Ostreacea] |–ChondrodontaHS02 [ChondrodontidaeBRW98] |–LithiotidaeBRW98 | |–Lithiotis problematica Gümbel 1874SB93 | `–Cochlearites loppianus (Tausch 1890)SB93 |–GryphaeidaeC04 | | i. s.: CrenostreaJB12 | | CeratostreonJB12 | | GyrostreaJB12 | |… Continue reading Ostreoidea

Belongs within: Ostreoidea.Contains: Ostrea. The Ostreinae are a group of oysters first known from the Middle Jurassic. Shells lack posterior grooves and have an umbonal cavity, chambers between shell layers, and a prismatic outer layer (Komatsu et al. 2002). A number of modern species are economically significant, such as the eastern oyster C. virginica of… Continue reading Ostreinae

Belongs within: Pectinidae. Pecten is a genus of scallops that is first known from the Upper Eocene. The valves of the shell are distinctly unequal, with the right valve being strongly convex and the left valve only slightly convex, flat or concave. Radial ribs are well developed with those on the more convex right valve… Continue reading Pecten

Belongs within: Aviculopectinoidea. Aviculopecten is a genus of scallops known from the Carboniferous and Permian. Shells are marked by radial ornamentation that increases by intercalation on the left valve but by bifurcation on the usually smaller right valve. Aviculopecten McCoy 1852W77 |–A. affinis de Koninck 1885SB93 |–A. alternatoplicatusG31 |–A. borealisG31 |–A. carboniferousG31 |–A. comelicanusG31 |–A.… Continue reading Aviculopecten