Oswaldella Stechow, 1919

Peña Cantero, A. L. & Vervoort, W., 2004, Species of Oswaldella Stechow, 1919 (Cnidaria: Hydrozoa: Kirchenpaueriidae) from US Antarctic expeditions, with the description of three new species, Journal of Natural History 38, pp. 805-861 : 811-812

Oswaldella Stechow, 1919

Oswaldella Stechow, 1919: 853 ; type, by original designation: Schizotricha bifurca, Hartlaub, 1904 .

Diagnosis (taken from Peña Cantero et al., 1997). Feather-like, colonial hydroids with branched or unbranched stem, divided into internodes or undivided, mono- or polysiphonic and with two longitudinal rows of apophyses, alternately arranged in one plane and supporting hydrocladia. Apophyses with varied number of nematophores on upper surface near axil with hydrocaulus, emerging through a raised, perforated part of the periderm (‘mamelon’) and / or through simple holes in the perisarc. Stem without nematophores or nematothecae. Hydrocladia typically branched. Degree of branching varied, fourth-order hydrocladia having been recorded. Hydrocladia homomerously divided into internodes (with the exception of Oswaldella herwigi El Beshbeeshy, 1991 ) bearing one hydrotheca and two nematophores each: one mesial superior nematophore and another mesial inferior. First nematophore placed behind free adcauline hydrothecal wall; second situated below hydrotheca at a more or less distinct elevation of internode. Mesial inferior nematophore with or without rudimentary, scale-shaped nematotheca. Hydrothecae cupshaped to tubular. Colonies dioecious, with sexual dimorphism. Gonothecae inserting on hydrocladia below hydrotheca next to mesial inferior nematophore. Cnidome composed of microbasic mastigophores, typically in two size classes.

List of species described in or now referred to Oswaldella

Oswaldella antarctica ( Jäderholm, 1904) (= Schizotricha antarctica Jäderholm, 1904 ) Oswaldella bifurca ( Hartlaub, 1904) (= Schizotricha bifurca Hartlaub, 1904 ) Oswaldella billardi Briggs, 1938

Oswaldella blanconae El Beshbeeshy, 1991

Oswaldella crassa Peña Cantero and Vervoort, 1998

Oswaldella curiosa Peña Cantero and Vervoort, 1998

Oswaldella delicata Peña Cantero, Svoboda and Vervoort, 1997

Oswaldella elongata Peña Cantero, García Carrascosa and Vervoort, 1995 Oswaldella encarnae Peña Cantero, Svoboda and Vervoort, 1997

Oswaldella erratum Peña Cantero and Vervoort, 1997

Oswaldella frigida sp. nov.

Oswaldella garciacarrascosai Peña Cantero, Svoboda and Vervoort, 1997 Oswaldella gracilis Peña Cantero, Svoboda and Vervoort, 1997

Oswaldella grandis Peña Cantero, Svoboda and Vervoort, 1997

Oswaldella herwigi El Beshbeeshy, 1991

Oswaldella incognita Peña Cantero, Svoboda and Vervoort, 1997

Oswaldella medeae sp. nov.

Oswaldella monomammillata sp. nov.

Oswaldella obscura Peña Cantero, Svoboda and Vervoort, 1997

Oswaldella rigida Peña Cantero, Svoboda and Vervoort, 1997

Oswaldella shetlandica Stepan’yants, 1979

Oswaldella stepanjantsae El Beshbeeshy, 1991

Oswaldella terranovae Peña Cantero and Vervoort, 1996

Oswaldella tottoni Peña Cantero and Vervoort, 1996

Oswaldella vervoorti Peña Cantero and García Carrascosa, 1998