Neithea coquandi (Péron, 1877)
PÉRON, A. 1877. Observations sur la Faune des Calcaires à Échinides de Rennes-les-Bains et sur quelques Fossiles du terrain crétacé supérieur. Bulletin de la Société Géologique de France [3e Série], 5: 499-535, pl. 7 [p. 504, pl. 7, figs. 2, 2a]
1862 Janira tricostata Coquand, 1862
1877 Janira coquandi Péron, 1877
1888 Janira welwitschi Choffat, 1888
1890 Pecten coquandi var. atropha Péron, 1890
1897 Vola cenomanensis Soehle, 1897
1912 Pecten (Neithea) shawi var. biatropha Pervinquière, 1912
1912 Pecten (Neithea) shawi Pervinquière, 1912
1916 Neithea angoliensis Newton, 1916
1937 Neithea quadricostata regoi Maury, 1937
1937 Neithea quadricostata lastroensis Maury, 1937
1979 Neithea (Neitheops) nana Ferreira & Klein, 1979
1877 Janira coquandi Péron, 1877
1888 Janira welwitschi Choffat, 1888
1890 Pecten coquandi var. atropha Péron, 1890
1897 Vola cenomanensis Soehle, 1897
1912 Pecten (Neithea) shawi var. biatropha Pervinquière, 1912
1912 Pecten (Neithea) shawi Pervinquière, 1912
1916 Neithea angoliensis Newton, 1916
1937 Neithea quadricostata regoi Maury, 1937
1937 Neithea quadricostata lastroensis Maury, 1937
1979 Neithea (Neitheops) nana Ferreira & Klein, 1979
A. Péron, 1877, plate 7.
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«En 1849, M . Bayle (3) a créé le Pecten tricostatus pour une espèce recueillie en Algérie par M . Fournel dans les couches de la Craie d'El Outaïa. Tout en reconnaissant que son espèce était identique avec la Janira Alpina, d'Orb., le savant paléontologiste a fait passer en synonymie ce dérider nom, qui cependant a la priorité. Si donc le rapprochement était exact, c'est le nom de J. Alpina qui devrait prévaloir; mais l'examen que j'ai pu faire du Pecten tricostatus, Bayle, à l'aide de bons échantillons recueillis dans les mêmes couches où M. Fournel a trouvé le sien, ne me permet pas d'accepter son assimilation à la Janira Alpina.
L'espèce qui nous occupe a bien, comme cette dernière, deux petites côtes entre les grosses; mais celles-ci sont en outre marquées de deux sillons latéraux qui dessinent, comme dans la J. substriatocostata, deux petites côtes latérales supplémentaires. C'est, en résumé, de cette dernière espèce que le Pecten tricostatus se rapproche le plus. Longtemps j'ai hésité à les réunir. Toutefois, quelques petites différences existant, notamment dans la saillie des grosses côtes, et l'identité n'étant pas parfaite, il me paraît préférable de conserver à l'espèce de M. Bayle le nom que ce géologue lui a donné, mais en la faisant passer dans le genre Janira. La J. tricostata, Coq., a été créée et décrite e n 1862 (1), non pas, comme on pourrait le croire, sur les mêmes échantillons que le Pecten tricostatus, Bayle, mais sur une autre espèce, très-abondante dans les couches cénomaniennes de Batna, Tebessa, etc. M. Coquand, tout en reconnaissant que son espèce est différente de celle de M. Bayle, qu'il considère comme devant être rapportée à la Janira quadricostata, reprend néanmoins le nom donné par M. Bayle, pour l'attribuer à son espèce de Batna. Il y a là un double emploi et une source d e confusion dont j'ai été à même de remarquer quelques fâcheuses conséquences. D'ailleurs la dénomination adoptée par M. Coquand est doublement défectueuse. Non-seulement elle fait double emploi avec celle attribuée antérieurement à une autre espèce, mais elle a aussi le tort de fausser le moyen diagnostique employé pour distinguer les diverses espèces. La J. tricostata, Coq., a en effet, commela J. quadricostata, une grosse côte de quatre en quatre, tandis que, suivant l'usage adopté, son nom indique qu'elle devrait en avoir une de trois en trois. Aussi c'est avec raison que M. Bayle avait appliqué cette dénomination à l'espèce de la Craie à Hemiaster Fourneli. Pour ces motifs, je pense qu'il n'est pas possible de conserver dans la méthode la Janira tricostata, Coq., et je propose de donner à l'espèce de Batna décrite sous ce nom, celui de J. Coquandi, sous lequel elle figure déjà dans ma collection. Le caractère principal de la J. Coquandi est d'avoir les trois petites côtes intermédiaires constamment et fortement inégales. La plus rapprochée du milieu de la coquille est toujours plus petite que les deux autres, qui sont elles-mêmes un peu inégales. Ces deux dernières sont arrondies et plus régulièrement espacées, et le sillon qu'elles laissent entre elles est moins grand qu'entre la dernière et la grosse côte voisine. Enfin la taille est plus grande que celle de la J. quadricostata, et la forme présente également des différences sensibles. Je fais figurer (Pl. VII, fig. 2 et 2 a, et 5-5 b) les J. Coquandi et J. tricostata pour montrer les caractères distinctits de ces deux espèces; malheureusement le dessin n'a rendu qu'imparfaitement la taille et la distance relatives des côtes.» ALPHONSE PÉRON, 1877
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«Some of our specimens differ from typical North African representatives of N. (N.) coquandi in having larger auricles (A.V. Dhondt, Brussels, personal communication, September 2002). However, in all other respects these specimens are typical N. (N.) coquandi.
Beurlen (1964a) assigned the specimens from Sergipe described by White (1887) and Maury (1937) as N. quadricostata to N. shawi Pervinquière, 1912, and mentioned their similarity to N. welwitschi (Choffat, 1888), probably on the basis of their strongly developed middle secondary ribs. Three specimens of Neithea from two localities (Santa Cruz and near Inhambupe) in the Tucano Sul Basin, Bahia collected by Melo Junior (1939) were described by Oliveira (1939) as N. sergipensis. However, judging from his description and illustration these specimens are not referable to N. (N.) hispanica, as are the types of N. sergipensis from Sergipe, but agree in all respects with N. (N.) coquandi. Neithea (Neitheops) nana Ferreira and Klein (in Klein and Ferreira, 1979) from the São Luís Basin, was based on few, poorly preserved specimens. The description and illustration fit the concept of N. (N.) coquandi and the two species are here synonymized. N. (N.) coquandi differs from N. (N.) alpina from the Albian of the Camamu Basin in having three, commonly unequal secondary ribs, with the middle one most strongly developed. There has been nomenclatorial confusion about N. (N.) coquandi, starting from the first description as Janira tricostata by Coquand (1862). For a discussion of the problem, see Dhondt (1973, p. 28).» ANDRADE, E. DE J., J. SEELING, P. BENGSTON & W. SOUZA-LIMA. 2004. The bivalve Neithea from the Cretaceous of Brazil. Journal of South American Earth Sciences, 17: 25-38, figs. 1-4. [p. 31, 32]
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Neithea (Neithea) coquandi (Peron): E. de J. Andrade et al., 2004, The bivalve Neithea from the Cretaceous of Brazil, figures 4.1-4.5.
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«Diagnosis.— Medium-sized to large Neithea-species, with very convex right valves and flattened to concave left valves. Six prominent principal ribs, between each two of those 3 unequal intercalary ribs. Areas inwardly bent. Auricles and areas
smooth. Right valve: beak is strongly incurved and narrow, thus giving the whole shell a slender appearance; U.P.D.>W. Left valve : flattened to concave; U.P.D. ≤W. Rib arrangement: 6 prominent principal ribs; in principle 3 intercalaries between each 2 principal ribs; the intercalaries are unequally developed and frequently not much more developed than filae. Nearly always the middle intercalary (the furthest away from the principal ribs) is more strongly developed than the side-intercalaries (those lying close to the principal ribs). Generally the ribs have a smooth appearance. Areas : strongly inwardly bent on the right valve; no ornamentation is present; sometimes however some folds, only vaguely delimited, can have the appearance of riblets. On some areas one of these folds is present, and very rarely there can be three. But even in the latter case the major part of the area is perfectly smooth. Auricles: very small, equal and smooth. Discussion:
Variability.— The proportions do not vary much; the most striking variable characteristic is in the relative rib development; intercalary ribs can: — be equal between much more developed principal ribs; — be unequal and have the middle intercalary more strongly developed than the side-intercalaries; — same situation as above but the middle-intercalaries are as strongly developed as the principal ribs: the shell looks as if there were 11 principal ribs with one intercalary in each interval; — one intercalary rib between each pair of principal ribs did not develop, or hardly (var. atropha PÉRON); — both side-intercalaries between each pair of principal ribs did not develop much (var. biatropha PERVINQUIÈRE); — var. biatropha with very strongly developed middle intercalaries with the aspects of principals ribs: shell with 11 equal ribs: can be compared with N. angoliensis NEWTON and N. decemcostata (D'ORBIGNY); — all ribs —principals as well as intercalaries— reach the same development: confusion with N. hispanica can arise, as far as the rib-arrangement is concerned. Synonymy.— The nomenclatorial confusion started from the very beginning of this species' description: H. COQUAND, 1862 gave it the name Janira tricostata without taking Pecten tricostatus BAYLE, 1848, also a Neithea, into consideration: thus COQUAND's name is a secondary homonym.
PÉRON corrected the nomenclature and changed it into Janira coquandi (PÉRON, 1877). PERVINQUIÈRE interpreted the nomenclature of this species wrongly on two points:
K. A. ZITTEL evidently knew the study by COQUAND, 1862. By wrongly naming his specimens of N. coquandi, Janira quadricostata, he has been the cause of much confusion: his figures and descriptions [except fig. 4 a = N. alpina (D'ORBIGNY)] correspond fully with N. coquandi and not with N. regularis (SCHLOTHEIM) = N. quadricostata (D'ORBIGNY, non SOWERBY). On his figured specimens it is impossible
to see the «concentrischen Linien» mentioned by him and the area riblets drawn on plate 18, figure 4 d: as stated in his text the areas are smooth except for a few filae. By not noticing the difference which exists between his specimens and N. regularis, he has overlooked one of the most striking faunal differences between Senonian North-European and Tethyan faunas. In Janira welwitschi, P. CHOFFAT described a typical example of an individual with middle intercalaries as strongly developed as the principal ribs. Vola cenomanensis U. SOEHLE, 1897 is based on very small Bavarian Cenomanian specimens; their size makes it extremely difficult to count the ribs. In the Bayerische Staatssammlung in Munich there are several specimens from the type-locality, Lichtenstättgraben near Ettal; if it were necessary, a lectotype could be chosen amongst them. Since the specimens are extremely small, pooriy developed ribs arc very easily overlooked. This explains why, for some individuals, the ribnumber is indicated as being as low as 17. Neithea angoliensis R. B. NEWTON is a very small and poorly preserved specimen; the ribs which can be seen make it probable that it is a N. coquandi in which the middle intercalary ribs have attained the same development as in the principal ribs.» DHONDT, A. V. 1973. Systematic revision of the subfamily Neitheinae (Pectinidae, Bivavia, Mollusca) of the European Cretaceus. Mémoires du Institute Royal des Sciences Naturelles de Belgique, 176: 1-101, pls. 1-5. [p. 27, 28]
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Neithea (Neithea) coquandi (Péron, 1877); A. V. Dhondt, 1973, Systematic revision of the subfamily Neitheinae of the European Cretaceus, plate 3, figures 1a-1c.
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