Review of the genus Odontophora (Nematoda: Axonolaimidae), with a key to valid species and description of Odontophora atrox sp. n. from the New Zealand coast.

Odontophora is a globally distributed marine nematode genus common in intertidal and subtidal sediments. Odontophora is one of the most diverse genus of the family Axonolaimidae with over 30 valid species described to date; however, the last revision of the genus was made over four decades ago. In addition, limited molecular sequence data are available for the Axonolaimidae and relationships among axonolaimid genera have not yet been investigated using molecular tools. Here, an updated list of species and a key for the identification of all 34 valid species is provided, and preliminary analyses of phylogenetic relationships within the Axonolaimidae are conducted using SSU and D2-D3 of LSU molecular sequences. Odontophora atrox sp. n. is described from intertidal sediments of Wellington, North Island of New Zealand, and is characterised by cephalic setae 1.1-1.5 corresponding body diam. long, 12 subcephalic setae, eight of which are slightly shorter and four of which are markedly shorter than the cephalic setae, excretory pore located slightly posterior to the amphids, and nerve ring located at two-thirds to three-quarters of pharynx length from anterior. Males are characterised by weakly arcuate spicules and tapering gubernacular apophyses, 9-10 small tubular precloacal supplements, cloacal aperture flanked by two sets of heavily cuticularised and eversible spines, and two elongated laterodorsal setae near the tail tip. Preliminary analyses of phylogenetic relationships within the Axonolaimidae provide some support for the monophyly of Odontophora, but drawing more solid inferences about relationships within the Axonolaimidae will require more molecular sequence data of accurately (and verifiably) identified species. [ABSTRACT FROM AUTHOR]