Camptonectes virdunensis (Buvignier, 1852)
BUVIGNIER, A. 1852. Statistique géologique, minéralogique, minérallurgique et paléontologique du Département de la Meuse. Atlas de 32 planches. 52 pp., pls. 1-32. J. B. Baillière, Paris. [p. 24, pl. 20, figs. 4-6]
1852 Pecten virdunensis Buvignier, 1852
1862 Pecten sahleri Étallon in Thurmann & Étallon, 1862
1862 Pecten waldeckensis Étallon in Thurmann & Étallon, 1862
1862 Pecten sahleri Étallon in Thurmann & Étallon, 1862
1862 Pecten waldeckensis Étallon in Thurmann & Étallon, 1862
A. Buvignier, 1852, plate 20.
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«P. testa ovali-elongata, depressa, inaequivalvi , inferne rotundata, superne acuta; concentrice et radiatim striata; striis radiantibus arcuatis, punctulatis, striis concentricis interruptis; valva sinistra convexiori; cardine recto; auriculis posticis, brevibus, obliquis; anticis majoribus.
Longueur 29 mill., hauteur 40, épaisseur 10.
Coquille ovale-allongée, aplatie, inéquivalve, arrondie inférieurement, et (en faisant abstraction des oreillettes) se terminant en pointe vers les crochets, stries rayonnantes arquées, laissant entr'elles des côtes légèrenlent convexes el se croisant avec des stries concentriques, interrompues sur les côtes, et très-marquées dans le fond des stries rayonnantes; valve gauche un peu plus bombée que l'autre; charnière droite; oreillettes postérieures courtes et obliques; les antérieures plus allongées; crochets aigus.
Des assises moyennes du coral-rag de Verdun. r.» AMAND BUVIGNIER, 1852
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«2. AMENDED DIAGNOSIS
Distinguished from all other species of C. (Camptonectes) by the consistently sub-ovate disc (H >L).
3. AMENDED DESCRIPTION
Essentially similar to C. (C.) auritus apart from the diagnostic feature (see Section 2), higher mean H/UA (text fig. 119), apparently isometric growth of H/L (text fig. 118) to the maximum height of 67.5 mm (GEMMELLARO and DI BLASI, 1874), somewhat weaker ornamentation and thinner shell. The sub-ovate form is illustrated in PI. 4, Figs. 1, 2.
4. DISCUSSION
BUVIGNIER's (1852) drawings of 'P.' Zieteneus and 'P.' Virdunensis are both based on specimens derived from U. Oxfordian reef facies. However, only that of 'P.' Virdunensis (1) definitely depicts the narrow C. (Camptonectes) species which is common in this facies (see Section 8) and described in Section 3. The dimensions of the figure of P. Zieteneus (2) plotwithin the ränge of the species described in Section 3 but the figure is an enlargement and DECHASEAUX (1936), who probably had access to the original, has referred to Camptonectes Zietenus specimens whose dimensions (3) are comparable with C. (C.) auritus, of which they would thus seem to be rare representatives from reef facies (see p. 123). Although PERON (1905) has applied the name 'P. ' zieteneus to specimens which are at least in part referable to the species described in Section 3, it seems preferable to adopt the name C. (C.) virdunensis for the latter until such time as the type material of 'P. ' Zieteneus (which would have priority as name bearer) is relocated and shown unequivocally to be representative of the species described in Section 3. The figure of 'P. ' suprajurensis BUVIGNIER (4) has metric proportions within the ränge of C. (C.) virdunensis but like that of 'P. ' Zieteneus is an enlargement. De LORIOL and PELLAT (1866) and PERON (1905), who may have had access to the original, have applied the specific name to specimens whose metric proportions (5 and 6 respectively) are comparable with C. (C.) auritus. However, de LORIOL et al. (1872) figure a specimen which seems to be representative of C. (C.) virdunensis under 'P.' suprajurensis. With the evident possibility of confusion the systematic affinities of the type material of 'P.' suprajurensis and of inadequately characterised specimens referred to the species in CONTEJEAN (1859), de LORIOL and COTTEAU (1868), de LORIOL and PELLAT (1875), SALIN (1935) and DECHASEAUX (1936) are best left an open question. Specimens referred to C. suprajurensis by SPÄTH (1936) can however definitely be placed in C. (C.) auritus (see p. 118).
'P.' Sableri ETALLON, 'P. ' titonius GEMMELLARO and DI BLASI and 'P. ' ledonicus de LORIOL are inseparable from C. (C.) virdunensis by their metric proportions (respectively 7, 8 and 9) and ornament. 'P.' Waldeckensis ETALLON is also inseparable by metric proportions (10) and the apparent lack of ornament can probably be attributed to abrasion. The original figure of 'P.' Flamandi CONTEJEAN has H/L (1 1) very similar to that of C. (C.) virdunensis but H/UA is abnormally small. While this might be due to inaccurate drawing the existence of quite strong comarginal ornament in addition to divaricate striae suggests that CONTEJEAN's species may be referable to C. (Camptochlamys) obscurus. Specimens figured under 'P.' Flamandi by de LORIOL and PELLAT (1875) may have similar affinities but those referred to CONTEJEAN's species by THURMANN and ETALLON (1862) and DECHASEAUX (1936) almost certainly belong in C. (C.) virdunensis. 'Chlamys' virdunensis (BUVIGNIER); COSSMANN was compared with 'P.' clathratus ROEMER while FAURE-MARGUERIT's (1920) record of GEMMELLARO and DI BLASI's species was based on specimens said to have 'quadrilateral' ornament. This suggests possible misapplication of these specific names to examples of C. (Camptochlamys). The affinities of 'P.' Buchi de LORIOL (non ROEMER) and 'P.' Delessei ETALLON are discussed under C. (C.) auritus.» JOHNSON, A. L. A. 1984. The palaeobiology of the bivalve families Pectinidae and Propeamussiidae in the Jurassic of Europe. Zitteliana, 11: 1-235, pls. 1-11. [p. 131, 132]
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Camptonectes (Camptonectes) virdunensis (Buvignier 1852); A. L. A. Johnson, 1984, The palaeobiology of the bivalve families Pectinidae and Propeamussiidae in the Jurassic of Europe, plate 4, figures 1, 2.
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