Robustochelia Kudinova-Pasternak, 1983

Wiak, Piotr Jó Ż & Błażewicz-Paszkowycz, Magdalena, 2007, New records of two rare genera, Monstrotanais Kudinova-Pasternak, 1981 and Robustochelia Kudinova-Pasternak, 1983 (Tanaidacea: Crustacea), Zootaxa 1505, pp. 19-35 : 26

Genus: Robustochelia Kudinova-Pasternak, 1983

Diagnosis: Antennule 5-articled. Antenna 6-articled, articles 2 and 3 with robust seta. Mandible molar pointed. Maxillule with spiniform setae and regular setae distally. Maxilliped palp robust; endites relatively small, with two setae and without tubercles. Cheliped robust, attached by ventral sidepiece; propodus and dactylus strongly chitinized. Pereopods 1–3 with coxa; merus, carpus and propodus with regular setae. Pereopods 4–6 merus and carpus with spiniform setae. Pleopods well developed. Uropod endopod 2-articled, exopod 1- articled.

Male: Similar to female, but antennule articles 1–3 clearly solid.

Type species: Robustochelia robusta ( Kudinova-Pasternak, 1970) .

Gender of generic name: Masculine.

Species included: Robustochelia angusticephala Kudinova-Pasternak, 1986 ; R. longa Kudinova-Pasternak, 1983 ; R. robusta ( Kudinova-Pasternak, 1970) ; R. virilis n. sp.

Remarks: A diagnosis of Robustochelia modified after Kudinova-Pasternak (1983), was presented by Larsen (2005: page 276). Taking the chance to examine the type species – Robustochelia robusta (Kudinova- Pasternak, 1970) we have presented an amended diagnosis of the genus. According to our observation the genus is not only defined by robust and heavily chitinized chelae, but also pointed mandibular molar and pleopods present in both sexes. A peculiar feature of the genus is setation of the pereopods that is regular in the first three pereopods and modified to short spiniform setae in pereopods 4–6. In such circumstances Robustochelia solida Larsen, 2005 that has a wide molar, strong setae in all pereopods and lacks pleopods in the female cannot be included in the genus. It is very probable that Larsen’s species represents a new genus that may be more closely related to Leptognathioides and Monstrotanais .

Bearing in mind the characters mentioned above, the newly defined genus Robustochelia shows some relation to Leptognathia in having a pointed molar, lacking tubercles on the maxilliped endites, having delicate setae together with spiniform setae on the maxillules and regular setae on pereopods 1–3. At the same time Robustochelia differs from Leptognathia by having minute setation on the labium, strong setae on pereopods 4–6 and a different type of male.