Entolioidesidae Kasum-Zade, 2003
KASUM-ZADE, A. A. 2003. Advance in research of mesozoic bivalve mollusks in Azerbaijan (Order Pectinoida: Revision and Systematics). 111 pp. Baku (in Russian; translated by Rosanne D’Aprile Johnson, VIARC, Smithsonian Institution).
«Subfamily Entolioidesiinae Kasum-Zade subfam. nov.
Type genus. Entolioides Allasinaz, 1972. Middle-Upper Triassic of the Alps.
Diagnosis. Shell is of roundedly oval outline with straight hinge margin and with almost equal auricles. Byssal notch is absent or scarcely visible. Surface of shell covered with radial sculpture, which is especially developed on left valve. Internal surface of shell usually smooth, more rarely ornamented (Filopecten). Composition. Entolioides Allasinaz, 1972; Filopecten Allasinaz, 1972; Comparison. It differs from the subfamily Entoliinae in having straight cardinal margin, in the presence of well-developed radial sculpture. To the subfamily being established it is conditionally possible to assign also Kolymonectes Milova et Polubotko, 1976 [type: Aequipecten (?) anjuensis Milova, 1969]. Range. Carnian Stage of the Triassic – basal levels of Lower Jurassic. Worldwide.» ANDREA ALLASINAZ, 2003
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«The new family Entolioididae differs from the Pernopectinidae in having scrolling, if present, better developed on the right auricles rather than on the left, less valve discordance in size and shape, and polygonal calcitic prisms in a random arrangement rather than regularly arranged hexagonal prisms. The outerligament articulation present in the Entolioididae and Entoliidae is reversed in comparison with that of the Pernopectinidae. Compared with the Entoliidae, the outer prismatic calcitic layer of the right valve in the Entolioididae is ontogenetically persistent, whereas in the Entoliidae it is limited to early ontogeny or absent. Compared with Triassic Propeamussiidae, the family Entolioididae lacks internal ribs. Compared with the groups in clade 8 (Fig. 1), members of the Entolioididae lack a deep byssal notch and associated fasciole in early ontogeny and lack coarse radial plication. Compared with smooth, amusiiform Pectinidae, members of the Entolioididae have ontogenetically persistent columnar prismatic calcite on the right valve and lack a ctenolium throughout ontogeny.
At this stage of research, four Triassic genera are regarded as members of the new family: Entolioides Allasinaz, 1972: 295, Filopecten Allasinaz, 1972: 301, Scythentolium Allasinaz, 1972: 308, and Calvaentolium Romanov, 1985. Crenamussium Newton (in Newton et al., 1987) is a junior synonym of Calvaentolium. In the Jurassic, Kolymonectes Milova & Polubotko (in Bychkov et al., 1976), is almost certainly a member of the Entolioididae based on the inferred presence of an ontogenetically persistent outer prismatic shell layer on its right valve, the lack of internal ribs, the lack of a ctenolium, and the presence of radial costae on the left valve exterior. Damborenea (1998) and Aberhan (1998) thought that this combination of characters indicated a separate stock in the family Propeamussiidae that lacked internal ribs, a view that is rejected herein on phylogenetic grounds. The Jurassic genera Pectinula Leanza, 1943, Posidonotis Losacco, 1942, and Amuropecten Sey, 1984 are possibly also entolioidids, although little is known about their shell microstructure (Damborenea, 1987; Aberhan & Pálfy, 1996; Aberhan, 1998; but see Hayami, 1988). On the basis of these genera, the total stratigraphic range of the Entolioididae is from Lower Triassic (Upper Scythian; Allasinaz, 1972) to Lower Jurassic (Toarcian; Westermann, 1992; Aberhan & Pálfy, 1996).» WALLER, T. R. 2006. Phylogeny of families in the Pectinoidea (Mollusca: Bivalvia): importance of the fossil record. Zoological Journal of the Linnean Society, 148: 313-342, figs. 1-12. [p. 321]
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