Sternostylus, Baba & Ahyong & Schnabel, 2018

Baba, Keiji, Ahyong, Shane T. & Schnabel, Kareen E., 2018, Rediagnosis of the squat lobster genus Gastroptychus Caullery, 1896, with a new genus Sternostylus and a new family Sternostylidae (Crustacea: Decapoda: Anomura: Chirostyloidea), Zootaxa 4524 (1), pp. 77-86 : 81-83

Sternostylus new genus

( Figs. 2A , 3B )

Ptychogaster — Henderson, 1888: 170 (part).— Alcock, 1901: 279 (part). Gastroptychus— Caullery, 1896: 390 (part).— Poore, 2004: 221 (part).— Baba, 2005: 19 (part).— Macpherson & Baba, 2011: 49 (part).

Type species. Ptychogaster formosus Filhol, 1884 .

Etymology. From the Greek sternon (= breast, sternum), plus stylus (= column, style), alluding to the unique shape of the sternal plastron, which distinguishes the genus from all genera of the Chirostylidae . Gender: masculine.

Diagnosis. As for family.

Species included. Gastroptychus cavimurus Baba, 1977b (eastern Pacific); Ptychogaster defensa Benedict, 1902 (eastern Pacific); Ptychogaster formosus Filhol, 1884 (eastern and northwestern Atlantic); Gastroptychus hawaiiensis Baba, 1977a (central Pacific); Ptychogaster hendersoni Alcock & Anderson, 1899 (Indian Ocean and western Pacific); Gastroptychus iaspis Baba & Haig, 1990 (eastern Pacific); Ptychogaster investigatoris Alcock & Anderson, 1899 (Indian Ocean and western Pacific); Gastroptychus meridionalis de Melo-Filho & de Melo, 2004 (western Atlantic); Ptychogaster milneedwardsi Henderson, 1885 (eastern Pacific [Strait of Magellan]); Chirostylus perarmatus Haig, 1968 (eastern Pacific); Gastroptychus rogeri Baba, 2000 (southwestern Pacific); Gastroptychus salvadori Rice & Miller, 1991 (western Atlantic).

Remarks. At present, the single genus Sternostylus is recognized for the 12 species assigned to the

Sternostylidae .

Figures

FIGURE 2. Anterior part of sternal plastron, with left and right maxillipeds 3, and left and right pereopod 1 coxae; maxillipeds 1 and 2 omitted. A, Sternostylus formosus (Filhol, 1884) n. comb., syntype, male, CL 16.7 mm, MNHN IU-2015-11878. B, Kiwa hirsuta Macpherson, Jones & Segonzac, 2005, holotype male, CL 51.5 mm, MNHN IU-2010-1683 (Ga 5310). C, Eumunida similior Baba, 1990, holotype, male, CL 33.1 mm, MNHN IU-2011-5516 (Ga 729). D, Pseudomunida fragilis Haig, 1979, female, CL 11.2 mm, NIWA 24583. Scales = 1 mm.

FIGURE 3. Pereopod 2 dactylus, distal part, setae omitted, lateral. A, Chirostylidae: Gastroptychus spinifer (A. Milne Edwards, 1880), syntype, female, CL 19.0 mm, MCZ CRU-4763. B, Sternostylidae: Sternostylus formosus (Filhol, 1884), n. comb., syntype, male, CL 16.7 mm, MNHN IU-2015-11878. C, Kiwaidae: Kiwa hirsuta Macpherson, Jones & Segonzac, 2005, holotype male, CL 51.5 mm, MNHN IU-2010-1683. D, Eumunididae: Eumunida similior Baba, 1990, holotype, male, CL 33.1 mm, MNHN IU-2011-5516.