Dhondtichlamys Waller, 2001
WALLER, T. R. 2001. Dhondtichlamys, a new name for Microchlamys Sobetski, 1977 (Mollusca: Bivalvia: Pectinidae), preoccupied by Microchlamys Cockerell, 1911 (Rhizopoda: Arcellinida). Proceedings of the Biological Society of Washington, 114 (4): 858-860. [p. 858]
«Sobetski (1977: 56) introduced a new subgenus. Chlamys (Microchlamys), for a group of Eurasian Upper Cretaceous bivalves of the tarnily Pectinidae. The type species designated by Sobetski is Pecten pulchellus Nilsson, 1827, the type stratum and locality of which are the Campanian greensands at Köpingemölla, Sweden (Dhondt 1972: 19). These Cretaceous glauconitic sandstones occur in the Köpinge district, which includes Köpingemölla, and are now referred to by the informal name "Köpinge sandstone." Christensen (1986) described two belemnite assemblages from it, the older indicating a latest Early Campanian age and the younger a middle Late Campanian age. Kennedy and Christensen (1997) recorded arnrnonites from this sandstone that indicated an age compatible with the younger belemnite assemblage. Nilsson's material likely came from that part of the Köpinge sandstone that yielded the ammonites and therefore is probably of middle Late Campanian age (W. K. Christensen, in litt.).
Vokes (1980: 229) reported that Sobetski's subgenus name is preoccupied by Microchlamys Cockerell, 1911 (a rhizopodan protozoan of the order Arcellinida). but Sobetski did not rename the taxon before his death in 1988. As required by the International Code of Zoological Nomenclature (Fourth Edition, Article 60.3), I replace Microchlamys Sobetski, 1977, with Dhondtichlamys, new name, based on the same type species, Pecten pulchellus (ICZN Recommendation 60A). The name honors Dr. Annie V. Dhondt, Koninklijk Belgisch Instituut voor Natuurwetenschappen, Brussels, for her many contributions to our knowledge of Cretaceous Pectinidae. She was the first (Dhondt 1972) to recognize the taxonomic significance of the group of species that Sobetski later named. In addition to the type species, Dhondtichlamys includes eight of the nine species that Sobetski (1977) included in Microchlamys: Pecten acuteplicatus Alth, 1850; P. arlesiensis Woods, 1902; P. campaniensis d'Orbigny, 1847; P. inflexus Hagenow, 1842; P. pugguardi Ravn, 1908; Chllamys (Microchlamys) subacutiformis Sobetski, 1977; P. subaratus Nilsson, 1827; and Chlamys (Aequipecten) wisniowskii Pasternak, 1961. He originally also included P. trisulcus Hagenow, 1842, but later (Sobetski in Sobetski et al. 1982) moved this species to Chlamys (Chlamys). Dhondt (1972) had earlier included essentially the same assemblage, with the addition of Pecten sarumensis Woods, 1902, under the now obsolete cornbination "Lyropecten (Aequipecten)." She determined that P. inflexus is a junior homonym, which she renamed Lyropecten (Aequipecten) subinflexus Dhondt, 1972. She also regarded Pecten puggaardi and probably also P. wisniowskii as junior synonyrns of Pecten campaniensis. Sobetski et al. (1982) added three new species, Chlamys (Microchlamys) acuticostata Sobetski, 1982, C. (M.) plestshejevi Sobetski, 1982, and C. (M.) entis Sobetski, 1982. Collectively, the above assemblage of species ranges in age from Albian to Maastrichtianand occurs in Great Britain, Eurasia, and Egypt. As noted by Dhondt (1972: 13, 40), the genus also includes a species from the Upper Cretaceous of eastern North America, Pecten venustus Morton, 1833. Darragh & Kendrick (1991: 55) described a new species, Chlamys (Microchlamys) propesalebrosa, from the Maastrichtian of northwestern Australia, this being the first record of the genus in the Southern Hemisphere. Stilwell (1998: 44), however, questioned this generic placement. It is likely that Dhondtichlamys survived the end-Cretaceous mass extinction (Waller 1991, Waller & Marincovich 1992), but Paleocene or Eocene specimens remain poorly documented (for example, Pecten farafrensis Zittel, 1883, a nomen nudum discussed by Dhondt 1972: 28). Waller (1991) and Waller & Marincovich (1992) used Microchlamys at the genus rather than the subgenus level for phylogenetic reasons, a usage that was followed by Dhondt et al. (1996: 57) and Dhondt & Jagt (1997: 44).» THOMAS RICHARD WALLER, 2001
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Pecten pulchellus; S. Nilsson, 1827, Petrificata suecana formationis cretaceae, plate 9, figure 12.
Lyropecten (Aequipecten) pulchellus (S. Nilsson, 1827); A. V. Dhondt, 1972, Systematic revision of the Chlamydinae (Pectinidae, Bivalvia, Mollusca) of the European Cretaceous. Part 2: Lyropecten, plate 1, figure 2a, 2b.
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