Danielopolina revised: Phylogenetic relationships of the extant genera of the family Thaumatocyprididae (Ostracoda: Myodocopa)

Abstract

The extant genera of the ostracod family Thaumatocyprididae are revised using the results of a phylogenetic analysis based on 54 morphological characters and 28 taxa. This revealed two main lineages within the family. There is a deep-sea lineage comprising the two species of ThaumatocyprisMüller, 1906, the thirteen species of ThaumatoconchaKornicker and Sohn, 1976 and a monotypic DanielopolinaKornicker and Sohn, 1976, comprising the type species D. carolynaeKornicker and Sohn, 1976 only. The second lineage contained cave taxa only, all formerly placed in Danielopolina but here transferred to the subgenus Danielopolina (Humphreysella) Kornicker and Danielopol, in Kornicker et al., 2006, which is raised to full genus status as Humphreysella Kornicker and Danielopol, in Kornicker et al., 2006. This accommodates H. orghidani (Danielopol, 1972) new combination, H. bahamensis (Kornicker and Iliffe, 1989a) new combination, H. baltanasi (Kornicker in Humphreys et al., 2009) new combination, H. elizabethae (Kornicker and Iliffe, 1992) new combination, H. exuma (Kornicker and Iliffe, 1998) new combination, H. kakuki (Kornicker and Iliffe, 2000) new combination, H. mexicana (Kornicker and Iliffe, 1989a) new combination, H. palmeri (Kornicker et al., 2007) new combination, H. phalanx (Kornicker and Iliffe, 1995) new combination, H. styx (Kornicker and Iliffe, 1989c) new combination and H. wilkensi (Hartmann, 1985) new combination. The position of the remaining species, Danielopolina kornickeriDanielopol et al., 2000, in phylogenetic analyses is unstable, but this species is here recognised as a distinct lineage within the family. A new genus Welesina is established to accommodate as its type species Welesina kornickeri (Danielopol et al., 2000) new combination. New diagnoses are provided for all five genera. A new species of Thaumatoconcha, T. angeli sp. nov., is described, based on material of both sexes collected from deep water in the North Atlantic, on the Iberian abyssal plain. It can be readily distinguished from its congeners by the presence of 2 small bristles on the compound third-fourth antennulary segment of the female, and by the setation of the third endopodal segment of the antenna of the female.