Draconema Cobb 1913

Genus Draconema Cobb, 1913

Synonymy: Decraemer et al. (1997): 187.

Diagnosis (after Allen & Noffsinger 1978; Decraemer et al. 1997, Venekey et al. 2005, emended): Draconematinae. First anterior 7–14 annules of the cuticle enlarged. Twelve CATs on rostrum in two transverse rows. Amphids on rostrum, usually loop-shaped in males, open spiral or unispiral in females. No postanal PATs.

Type species: Draconema cephalatum Cobb, 1913.

The first extensive review of the genus Draconema was undertaken by Allen & Noffsinger (1978). They listed six valid species, two of them were described new for science (D. chilense Allen & Noffsinger, 1978 from Chile and D. antarcticum Allen & Noffsinger, 1978 from Antarctica) and four known species were redescribed from type specimens (D. cephalatum Cobb, 1913, Jamaica) or from specimens from the type or other localities (D. haswelli (Irwin– Smith, 1918), from the type locality of New South Wales, Australia; D. claparedii (Metscnikoff 1867), from Naples, Italy close to the type locality; D. ophicephalum (Claparéde 1863), from Naples, Italy and Marseille, France while the type locality is Normandy, France). Redescriptions of the older species D. claparedii (Metscnikoff, 1867), D. haswelli (Irwin-Smith, 1918) and D. ophicephalum (Claparède, 1863) were supplied with long lists of junior synonyms. Decraemer et al. (1977) reviewed Draconematidae and largely accepted the synonymization of Allen & Noffsinger. They listed seven valid species of Draconema, with the addition of D. japonicum Kito, 1976 (Kito 1976, 1979). A few new Draconema species have been recorded since. Venekey et al. (2005) described two new species D. brasiliensis and D. fluminensis from Brazil and provided a useful table summarizing mensural and numerical characters of all valid species of the genus. Kito & Chatterjee (2012) added a further new species D. andamanense from the coast of Andaman Islands, Indian Ocean, and a dichotomous key for the identification all valid Draconema species known by that time.

At about the same time, Rho & Min (2011) recorded the species D. hoonsooi Rho & Kim and D. youngeouni Rho & Kim from around the Korean Peninsula. There are several ambiguities with the two latter species in that publication. First, their scientific names are provided with neither year of publication, nor indication of type material. Second, drawings (habitus) and measurements are given for only one male but 15 males and 11 males were examined respectively for both D. hoonsooi and D. youngeouni. Though the descriptions are detailed and the drawings are fine and apparently precise, we accept here that the names D. hoonsooi and D. youngeouni are invalid based on Paragraph 16.1 of ICZN (1999). A summarized list of ten valid Draconema species is presented below.