Gilvossius Manning and Felder, 1992

Poore, Gary C. B., Dworschak, Peter C., Robles, Rafael, Mantelatto, Fernando L. & Felder, Darryl L., 2019, A new classification of Callianassidae and related families (Crustacea: Decapoda: Axiidea) derived from a molecular phylogeny with morphological support, Memoirs of Museum Victoria (Mem. Mus. Vic.) 78, pp. 73-146 : 94

Gilvossius Manning and Felder, 1992

Gebios Risso, 1822: 243 (type species, Gebios davianus Risso, 1822 , junior subjective synonym of Cancer candidus Olivi, 1792 , by monotypy) nomen oblitum.

Gebius Agassiz, 1846: 160 (unjustified emendation of Gebios Risso, 1822 ).

Gilvossius Manning and Felder, 1992: 558 .— Sakai, 2011: 372 (partim).

Pestarella Ngoc-Ho, 2003: 475 (type species: Astacus tyrrhenus Petagna, 1792 , by original designation).

Type species. Gonodactylus setimanus DeKay, 1844 , by original designation and monotypy.

Diagnosis. Rostrum obsolete or obtusely triangular, flat, not reaching cornea. Pleomere 1 tergite fused, divided into 2 sections by transverse step. Antennular peduncle length about 2.5–3 times the width of both eyestalks, length exceeding narrower antennal peduncle. Maxilliped 3 merus wider at ischium-merus suture than long. Male major cheliped merus with prominent truncate hook armed with serrations along lower margin, excavate laterally at base. Pereopod 3 propodus rectangular, lower margin deeply convex, leading to broadly rounded free proximal lobe. Male pleopod 2 present or absent. Uropodal endopod ovoid, usually longer than wide, anterior margin straight or slightly convex, posterodistal margin evenly convex. Telson wider than long, almost semicircular; or rarely posterior margin subtruncate.

Remarks. The genus is recognised by the telson being wider than long, almost semicircular in most species, but rarely subtruncate posteriorly. Gilvossius differs from Trypaea , Arenallianassa and Paratrypaea , which share uropodal exopods with densely setose margins, in lacking a deep notch at the base of the cheliped fingers and lacking a facial distal transverse row of short spiniform setae on the uropodal endopod.

Manning and Felder (1992) and Ngoc-Ho (2003) compared Gilvossius and Pestarella respectively with Callianassa , but this latter genus is only remotely similar in Robles et al.’s (in press) analyses. Both Pestarella and Gilvossius are in the recent literature. Gilvossius was erected for a single species, Gonodactylus setimanus , shown by molecular and morphological evidence (Robles et al., in press) to be congeneric with Gilvossius tyrrhenus , G. candidus and G. whitei ( Sakai, 1999a) . Ngoc-Ho (2003) erected Pestarella for the type species ( Astacus tyrrhenus ), G. candidus and three others; Pestarella is here treated as a subjective junior synonym of Gilvossius .

Gebios davianus Risso, 1822 , is generally agreed to be a junior subjective synonym of Cancer candidus Olivi, 1792 . Gebios , therefore, could be invoked as a senior subjective synonym of both Pestarella Ngoc-Ho, 2003, and Gilvossius Manning and Felder, 1992 . However, Gebios has never been used as a generic name. Ngoc-Ho (2003) provided a comprehensive synonymy of Pestarella , a junior synonym of Gilvossius , and its included species. The conditions of the International Code of Zoological Nomenclature Article 23.9.1 required for prevailing usage are met. We therefore invoke International Code of Zoological Nomenclature Article 23.9 and designate Gebios Risso, 1822 , as nomen oblitum and both Pestarella Ngoc-Ho, 2003, and Gilvossius Manning and Felder, 1992 , as nomina protecta.