Chirostylidae Ortmann, 1892

Schnabel, Kareen E. & Ahyong, Shane T., 2010, A new classification of the Chirostyloidea (Crustacea: Decapoda: Anomura), Zootaxa 2687 (1), pp. 56-64 : 58

Chirostylidae Ortmann, 1892

( Fig. 2C–F, I–L )

Diptycinés A. Milne-Edwards & Bouvier, 1894: 296, 312; 1897: 116 [vernacular name, unavailable].

Diptyciens A. Milne-Edwards & Bouvier, 1894: 299. — Bouvier, 1896: 312 [vernacular name, unavailable].

Diptycinae Bouvier, 1896: 312. — A. Milne-Edwards & Bouvier, 1899: 71, 87; 1900: 350.

Chirostylidae Ortmann, 1892: 244 .

Uroptychidae Alcock, 1901: 236, 278.

Diagnosis. Carapace surface smooth, tuberculate or spinose but without transverse striae, posterolateral margin not distinctly defined or greatly inflated; rostrum variously shaped; supraocular spines absent. Anterolateral margin of abdominal somite 2 without prominent, anterolaterally directed spine. Sternite 3 not strongly produced anteriorly. Eyes well developed. Basal antennular article with distolateral spines. Antennal peduncle consisting of 5 articles; acicle present or absent. Mandibular cutting edge calcified, strongly serrated along its length. Maxilliped 1 without epipod; exopod flagellum present or absent, not annulated. Maxilliped 3 to pereopod 4 each with 2 arthrobranchs (well-developed or vestigial on maxilliped 3). Pereopod 5 with 1 arthrobranch only. Pereopods 2–4 with pleurobranch. Male pleopods 1 and 2 present. Male pleopods 3–5 vestigial or absent.

Type genus. Chirostylus Ortmann, 1892 , by original designation.

Composition. Chirostylus Ortmann, 1892 , Gastroptychus Caullery, 1896 , Hapaloptyx Stebbing, 1920 , Uroptychodes Baba, 2004 , Uroptychus Henderson, 1888 .

Remarks. Pleopods 3–5 are absent in most male chirostylids, but are vestigial in some species of Gastroptychus (e.g., G. rogeri Baba, 2000 , and G. investigatoris ( Alcock & Anderson, 1899) , K. Baba, pers. com.; AM P53251, G. rogeri ).

Figures

FIGURE 2. A–F, mandibular dentition, ventral view. G–L, right maxilliped 1 endopod and exopod, anterior view (epipod indicated by arrow). Eumunididae: A, G, Eumunida australis de Saint Laurent & Macpherson, 1990b (♂, pcl 12.9 mm, NMNZ Cr.21765); B, H, Pseudomunida fragilis Haig, 1979 (♀ ovig., pcl 20.5 mm, MNHN-Ga7507). Chirostylidae: C, I, Chirostylus dolichopus Ortmann, 1892 (♂, pcl 2.7 mm, MNHN station LA REUNION, MD32, CP172); D, J, Gastroptychus rogeri Baba, 2000 (♂, pcl 23.2 mm, NIWA 14555); E, K, Uroptychodes epigaster Baba, 2004 (♀, pcl 3.4 mm, NMNZ Cr.21766); F, L, Uroptychus cardus Ahyong & Poore, 2004 (♂, pcl 10.5 mm, NIWA 23086). Scale: A–F, not to scale; G, H, J, L = 1.00 mm; I, K = 0.45 mm.