Talochlamys Iredale, 1929
IREDALE, T. 1929. Mollusca from the continental shelf of eastern Australia. No .2. Records of the Australian Museum, 17: 157-189. [p. 164]
«The form famigerator seems to represent an arrested stage in the development of Mimachlamys, apparently never growing to a large size and being always less convex, with a more suppressed sculpture. It may be named Talochlamys, subgen. nov.»
TOM IREDALE, 1929
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Chlamys famigerator Iredale; T. Iredale, 1925, Mollusca from the continental shelf of eastern Australia, plate 41, figures 1, 2
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Talochlamys pulleineana (Tate); H. H. Dijkstra & A. G. Beu, 2018, Living scallops of Australia and adjacent waters, figures 84D, 84E, 84G.
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«Talochlamys Iredale, 1929
Talochlamys Iredale, 1929: 188. Type species (by original designation): Chlamys famigerator Iredale, 1925 (= Pecten pulleineanus Tate, 1887), Recent, southern and eastern Australia.
Diagnosis. Small to medium-sized, byssate Pedini with unevenly spaced squamose primary radial costae or narrow plicae, and with secondary interstitial (mimachlamydoid-like) riblets in late ontogeny; microsculpture of weak antimarginal striae (also lacking in late ontogeny) and interstitial, widely spaced, prominent commarginal lamellae; shagreen microsculpture absent from post-Eocene species; internal rib carinae lacking; weak dorsal and resilial hinge teeth; byssal notch deep, ctenolium prominent.
Distribution. Paleocene–Recent (Beu & Darragh, 2001; del Rio & Martinez, 2015: appendix 1). Eastern Atlantic, Indo-West Pacific, southern Australia and New Zealand, living in the littoral to bathyal zones.
Discussion. Hertlein (1969: N355) treated Talochlamys as a junior synonym of Chlamys Röding, 1798, placed in the suprageneric Chlamys group. Waller (1993: 202) considered Talochlamys to be a valid genus of Chlamydini (i.e., Pedini).
Beu (1995: 18) for the first time included several fossil and Recent species from New Zealand in Talochlamys (see also Beu & Darragh, 2001; Dijkstra & Marshall, 2008).» DIJKSTRA, H. H. & A. G. BEU. 2018. Living scallops of Australia and adjacent waters (Mollusca: Bivalvia: Pectinoidea: Propeamussiidae, Cyclochlamydidae and Pectinidae). Records of the Australian Museum, 70 (2): 113-330, figs. 1-102. [p. 268]
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Talochlamys dichroa (Suter); A. G. Beu, 1995, Pliocene Limestones and their scallops, figures 4e-4h.
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«Genus Talochlamys Iredale, 1929
Talochlamys Iredale 1929, p. 164.
TYPE SPECIES (by original designation, (Iredale 1929, p. 188): Chlamys famigerator Iredale, 1925 (= Pecten pulleineanus Tate, 1887), Recent, southern and eastem Australia.
REMARKS: Waller (1993, p. 202) included Talochlamys in Tribe Chlamydini, and this position is confirmed by is lack of internal rib carinae at all growth stages.
The "holotype" of "Chlamys" famigerator Iredale (1925, p. 252, pl. 41, fig. 1, 2), type species of Talochlamys, has been examined (Australian Museum, Sydney, C53767,90-120 m, off Green Cape, southem New SouthWales) and, although hedale clearly regarded the two valves he described and illusraed as belonging to one specimen, they are actually unmatching valves from distinct specimens. The right valve is a somewhat abraded stained, narrowly costate specimen, shown even by Iredale's (1925, p. 253) own dimensions to be 2 mm shorter than the left valve. The left valve is a markedly cleaner, more brightly coloured specimen with high, wide, convex-topped radial costae. These are therefore clearly two syntypes, and the left valve is here designated the lecotype of Chlamys famigerator Iredale, 1925.
Iredale (1925, p. 253) pointed out that Talochlamys famigerator (i.e. T. pulleineana Tate) is closely related to "Pecten (Chlamys) dichrous Suter, from New Zealand", and this was borne out by deailed comparison. The two species share early dissoconch preradial microsculpture of Camptonectes antimarginal ridglets crossed by quite prominent commarginal ridges (Fig. 3f, g), passing down the disc into regular, prominent, widely spaced commarginal lamellae on the radial interspaces, the lamellae finely senated by the antimarginal ridgelets (Fig. 3e, h); major costae increase in number by intercalation in the centre of rib interspaces (Fig. 3f); and some specimens, at least, have wide, weakly convex-topped primary costae bearing, on some costae only of most specimens, prominent, high, wide, ventrally concave scales (Fig. 3h). T. pulleineana is widespread around southern Australia (Australian Museum, Sydney, 186 lots examined, ranging from southern Western Australia to Newcastle and Port Macquarie in New South Wales) whereas T. dichroa has a highly disjunct distribution in New Zealand (Museum of New Zealand, Wellington: South Island east coast to Campbell Plateau, 15 lots; southemmost: M.58912, BS583, Pukaki Rise, 49º08'S, 171º43'E, 160-186 m, FRV "James Cook", 14 Jan. 1977, many small shells; northemmost: M. 64680, wall of Pegasus Canyon, north of Banks Peninsula, 183-329 m, many valves; Snares Islands, 70-110 m, one lot (M.80501, 3 valves); Chatham Island 2 los (M.6582,4 valves; M. 6589, one valve); and Th¡ee Kings Islands area of northernmost North Island, 7 lots, collected in 88-210 m, each with many valves). Both species are highly variable in sculpture but much less variable in coloration than, for example, other New Zealand Chlamydini. Both are usually pale to dark orange, some specimens broadly banded in paler and darker orange, although a few specimens of T. dichroa are bright yellow or deep rose pink. A majority of specimens of both species has narrow-crested primary costae of triangular section and numerous finely scaly secondary and tertiary costellae (the form named Chlamys taiaroa in New Zealand by Powell (1952, p. 169, pl. 35, fig. 1)) but, in both species, this intergrades completely with the less common wide-ribbed specimens. In both species, which costae bear large, ventrally concave scales seems completely random; from one o four smooth costae between scaly ones seems to be normal variation, and some specimens (more commonly in T. dichroa than T. pulleineana) have all costae scaly. The lectotype of Chlamys famigerator has six costae scaly out of 23 (the third, seventh, twelfth, seventeenth, twentieth and twenty-second from the anterior).»
BEU, A. G. 1995. Pliocene Limestones and their scallops. Lithostratigraphy, pectinid biostratigraphy, and paleogeography of eastern North Island late Neogene limestone. Institute of Geological & Nuclear Sciences Monograph, 10: 1-243, figs. 1-95. (New Zealand Geological Survey Paleontological Bulletin, 68). Institute of Geological and Nuclear Sciences, Ltd., Lower Hutt, New Zealand. [p. 17, 18]
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