Eucalathis Fischer and Oehlert, 1890

Kaim, Andrzej, Bitner, Maria Aleksandra, Jenkins, Robert G. & Hikida, Yoshinori, 2010, A monospecific assemblage of terebratulide brachiopods in the Upper Cretaceous seep deposits of Omagari, Hokkaido, Japan, Acta Palaeontologica Polonica 55 (1), pp. 73-84 : 77-78

Genus Eucalathis Fischer and Oehlert, 1890

Type species: Terebratulina murrayi Davidson, 1878 by original designation of Fischer and Oehlert (1890: 72); Recent, 28°33’S, 177°50’W, near Kermadec Islands, depth 1080 m ( Davidson 1878).

Remarks.—Today Eucalathis has a worldwide distribution, being known from the Caribbean, Atlantic, Indian, Pacific, and Antarctic Oceans ( Cooper 1973a, b, c, 1977, 1981a, b; Foster 1974; Brunton and Curry 1979; Logan 1983, 1988, 1990, 1998, 2007; Zezina 1985, 1987, 2006; Hiller 1986,

doi:10.4202/app.2009.0068

1994; Dawson 1991; Laurin 1997; Gaspard 2003; Álvarez and Emig 2005; Bitner 2006, 2008, 2009). The 13 Recent species assigned to this genus exhibit a wide bathymetric range from 185 to 3870 m ( Logan 2007); one deep−water species, E. macroctena , included to Eucalathis by Zezina (1981), has recently been transferred into a new genus Melvicalathis Lee, Lüter, and Zezina, 2008 ( Lee et al. 2008). Melvicalathis can be easily distinguished from Eucalathis by its broad, smooth, triangular in cross−section ribs.

In the fossil record Eucalathis is very rare and has been so far reported from the Eocene of Eastern Coast of America ( Cooper 1988) and Miocene of Italy ( Davidson 1870; Lee et al. 2006). Those fossil species are coarsely ribbed, and thus differ strongly from the specimens described here. Apart from morphological differences, the great stratigraphical gap between the hitherto described Eucalathis species and the Late Cretaceous species from Japan justifies the decision to erect a new species. The studied specimens represent not only the first record of Eucalathis from Japan but also the oldest occurrence of the genus.