Paroriverutus, Carbonell and Coomans, 1982

Peña-Santiago, Reyes, Liébanas, Gracia & Ahmad, Wasim, 2014, Taxonomy of the genus Oriverutus Siddiqi, 1971 (Nematoda: Dorylaimida: Nordiidae), Journal of Natural History 48 (21), pp. 1253-1278 : 1264

Paroriverutus

This genus was described by Carbonell and Coomans (1982), with P. ivorensis from the Ivory Coast as its type and only species. The new taxon, morphologically close to Oriverutus , was separated from this (p. 899) “in having a longer odontostyle, more posterior position of guiding ring, more posterior position of S 1 N 1 and S 1 O 2, less developed glandular tissue at the pharyngo-intestinal junction and much longer tail”. After describing three new Oriverutus species with comparatively long odontostyle, weakly developed glandular tissue near the cardia and/or conical elongate caudal region, Ahmad and Siddiqi (1997) considered that differences between both genera were not enough to maintain separate generic status, synonymised Paroriverutus with Oriverutus , and transferred P. ivorensis to Oriverutus . This action was accepted by Andrássy (2002, 2009). The excellent original description of Paroriverutus allows re-evaluating and updating its comparison with Oriverutus . Three relevant features of this genus, namely lip region hemispherical with completely fused lips, guiding ring double and tail long in both sexes (196– 232 µm, c = 6.2–6.9, c' = 8.4–9.0 in females), conform to a morphological pattern that significantly differs from that observed in Oriverutus and support the separation of both taxa. Consequently, Paroriverutus is considered to be a valid taxon, distinguishable from Oriverutus by its lip region hemispherical with amalgamated (versus distinctly separated, lobe-like) lips, double (versus simple) guiding ring, and longer caudal region (> 190 versus <160 µm).

Andrássy (1971) described the new species Drepanodorylaimus macramphidius from Angola, which, three decades later (2002), was transferred to Oriverutus by the same author. This species is characterized by, among other features, its lip region with amalgamated lips, double guiding ring and long female tail (152 µm, c = 8.3, c' = 9.5), which is very similar to those found in Paroriverutus pattern.