Hinnites corallinus G. B. Sowerby I, 1827
SOWERBY I, G. B. 1827. Observations on the shells of an acephalous molluscum of the family of Pectinidae, for which the generic name of Hinnites has been proposed by M. Defrance; together with the characters of several species. The Zoological Journal, 3 (9): 67-72. [p. 71]
1827 Hinnites corallinus G. B. Sowerby I, 1827
1984 Hinnites spectabilis Cosel & Gofas, 1984
1984 Hinnites spectabilis Cosel & Gofas, 1984
Pecten (Hinnites) corallinus Sowerby. H.C. Küster & W. Kobelt, 1888, Die Gattungen Spondylus und Pecten, plate 69, figure 1.
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«Testa valde irregulari, extus corallino-rubra, valva superiore radiatim costellata, costellis muricato-subasperis intus pallide subfusca, marginibus basalibus sordide purpureis; long, et Alt. subaequalibus.
Shell very irregular, outside of a fine coral red, upper valve with small radiating ribs, here and there muricated; inside pale subfuscous, basal margins dull purple; muscular impression having the appearance of a horny substance veined with the same as the other parts of the inside, its lower edges variegated with pale dull purple: inside composed of a distinctly facetted crystalline substance, with occasional black coriaceous spots near the edges. Lower valve paler in colour than the upper; very rough with the irregularities of the sandstone rock on which it has been placed. The only specimen I have seen is in the collection of the Rev. Dr. Goodall; it was brought to England lately, from the eastern coast of Africa. Some Serpulae and a Balanus are attached to it.» GEORGE BRETTINGHAM SOWERBY I, 1827
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«The search for evidence of dispersal of Laevichlamys between the Indian Ocean and the Atlantic has led to one of the most surprising findings of the present study. A probable descendant from Laevichlamys turns out to be an extant cemented species of the eastern Atlantic, Hinnites corallinus (G.B. Sowerby I, 1827), which in turn may prove to be the same as the presumably extinct type species of the genus Hinnites, H. crispus (Brocchi, 1814), known mainly from the Mediterranean Pliocene. The evidence that has led to this interpretation is as follows:
1) Specimens reported by Kensley (1985) from Namibia were determined by me (pers. comm. to Kensley, 1985) to represent two species of "Hinnites". One of these, found in Cape Province, South Africa, is the familiar "Hinnites" ercolanianus (Cocconi, 1873), previously known from the Angolan coast (see Adam, 1960). As mentioned above, "H." ercolanianus is derived from a shagreen-bearing ancestor and is probably referable to Chlamys, sensu stricto. In the same personal communication quoted by Kensley, I suggested that the second species from Namibia is possibly new. It was distinguished from the former on the basis of the macro- and microsculpture of the early Chlamys stage. As shown in Figures 4o to 4r, this Namibian Hinnites has a pattern of rib introduction like that present in Laevichlamys, where rib interspaces are filled by the repeated medial intercalation of new radial costae. Furthermore, a close relationship to L. squamosa is indicated by auricular shapes, the dorsal margin of the right anterior auricle extending prominently above the hinge line and the posterior margin of the posterior auricle exhibiting a convex outline tending to form an oblique angle with the hinge. Lastly, some specimens of the Namibian species show the minute net of white pigment lines that is common in species above Node 7b in Figure 3. Although Kensley (1985) thought that the specimens of this Namibian species were fossil, the immature shells show little sign of wear and have adhering ligamental material. 2) Cosel and Gofas (1984), in a paper that I received after the aforementioned identification for Kensley (1985) was completed, described a new cemented pectinid species, Hinnites spectabilis Cosel and Gofas, 1984, which they reported as living along the southern part of the coast of Angola. Their description and illustrations leave no doubt that this is the same as the Namibian species. 3) Cosel (pers. comm., August, 1992) examined the type specimen of Hinnites corallinus G. B. Sowerby I, 1827, originally said to come from East Africa, and determined that it is the same as the species that he and Gofas (1984) had described as new. The East African locality is apparently in error. 4) The macro- and microsculpture of the Chlamys stage of Hinnites corallinus is remarkably similar to that of the type species of Hinnites. The latter is H. crispus (Brocchi, 1814), a fossil originally described from the Pliocene of Italy. The fossil species tends to be larger in size and thicker shelled than the living one, but there are broad similarities in form as well as in sculptural detail (see Roger, 1939). It is possible that these differences are ecophenotypic and that these species may be synonymous, in which case the living east African specimens are but a relic of a previously more broadly distributed species. 5) If it is true that Hinnites crispus is derived from an ancestral species in the new genus Laevichlamys, then the fossil record of H. crispus tends to support the idea that Laevichlamys did not enter the Atlantic by westward dispersal across the proto-Mediterranean. This is because the oldest specimens of H. crispus are known not from the Mediterranean but from the Atlantic side of France (Helvetian of the Aquitaine Basin and Loire Valley; Roger, 1939). Although the species has been reported from the late Miocene (Tortonian) of Austria, Hungary, and Bulgaria (Cuenca, 1980: 62; Raffi: 1971:124), it did not become widely distributed in the Mediterranean until the Pliocene, at which time it also extended as far as the British Isles (Roger, 1939: 174). Roger (1939: 174) thought that the species persisted into the late Pleistocene (Sicilian) in the western Mediterranean based on specimens from the Alpes-Maritimes region of France. Unfortunately, there is no Miocene or Pliocene fossil record of H. crispus (or H. corallinus) in southern Africa, nor is there any fossil record of a preceding free-living Laevichlamys in the eastern Atlantic. 6) The fossil record of the Caribbean species, Laevichlamys multisquamata, discussed below, is no older than Pleistocene.» WALLER, T. R. 1993. The evolution of Chlamys (Mollusca: Bivalvia: Pectinidae) in the tropical western Atlantic and eastern Pacific. American Malacological Bulletin, 10 (2): 195-249, figs. 1-14. [p. 203, 204]
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Hinnites corallinus G.B. Sowerby I, 1827; T.R. Waller, 2003, The Evolution of Chlamys, figures 4o-4r.
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