Dulichiella cuvettensis Appadoo & Myers, 2005

Published, First, 2007, A revision of the tropical / temperate amphipod genus Dulichiella Stout, 1912, and the description of a new Atlantic genus Verdeia gen. nov. (Crustacea: Amphipoda: Melitidae), Zootaxa 1424, pp. 1-62 : 24-27

Dulichiella cuvettensis Appadoo & Myers, 2005

( Figs 17–18)

Dulichiella appendiculata . – Ledoyer, 1986: 187, fig. 9 (Mau).

Dulichiella cuvettensis Appadoo & Myers, 2005: 225 , fig. 4.

Type material. Holotype male, 5 mm, AM P67233, La Cuvette , Mauritius (20°00'S 57°34'12"E), Sargassum sp. , 1 m, C. Appadoo, 12 October 1999 . Paratypes 3 specimens (1 female, 7 mm, 2 males, AM P67234), Bain Boeuf , Mauritius (19°59'S 57°36'E), Sargassum sp. and Pocockiella variegata , 1 m, C. Appadoo, 12 October 1999 .

Type locality. Among Sargassum sp. , La Cuvette, Mauritius (20°00'N 57°34.2'E) .

Description. Based on holotype male, 5 mm, AM P67233 and paratype female, 7 mm, AM P67234. Body small. Head eyes round; lateral cephalic lobe broad, truncated, anteroventral corner with slender setae. Antenna 1 peduncular article 1 shorter than article 2, with 3 robust setae along posterior margin. Antenna 2 peduncular article 4 subequal to article 5. Mandibular palp article 1 about twice as long as broad, inner margin article 1 produced distally; article 2 shorter than article 3.

Gnathopod 1 coxa anteroventral corner not produced, anterior margin straight, posteroventral corner notch present; carpus longer than propodus; propodus small, linear, palm straight, defined by posterodistal corner, with posterodistal robust setae. Gnathopod 2 coxa posteroventral corner notch present; (larger) propodus distolateral crown with 4 rounded spines, palm sinusoidal, posterodistal corner produced, slightly upturned, dactylus fitting against corner; dactylus apically blunt; (smaller) merus with sharp posteroventral spine; palm straight, margin without robust setae, corner with robust setae; with 1 or 2 setae on anterior margin. Pereopod 4 dactylar unguis anterior margin with 2 accessory spines. Pereopods 6 basis and merus without bunches of long slender setae (distal articles unknown). Pereopod 7 unknown.

Pleonite/urosomite dorsal spine formula (7-7-7-5-4-2). Pleonites 1–3 with sparse dorsal setae. Epimeron 1 posteroventral corner with small acute or subacute spine. Epimeron 2 posteroventral corner acute. Epimeron 3 posteroventral margin smooth. Urosomite 1 with spine at midline, no conspicuous medial gape. Urosomite 2 with two groups of 1–3 small dorsolateral robust setae. Urosomite 3 without dorsal setae; with 2 dorsal spines. Uropod 3 outer ramus very long, about 2 x peduncle. Telson with dorsal robust setae.

Female (sexually dimorphic characters). Gnathopod 2 subequal in size, similar to smaller gnathopod 2 of male; palm concave; dactylus posterior margin crenulate. Pereopod 7 basis expanded, posterior margin slightly convex, tapering distally.

Habitat. Marine epibenthic, living on mixed algae such as Padina , Pocockiella , Sargassum , Turbinaria and Ulva , intertidal.

Remarks. Dulichiella cuvettensis has four spines on the distolateral crown of male gnathopod 2 and a 7- 7-7-5-4-2 pleonite/urosomite formula. Four other species share these characters: the Atlantic species D. appendiculata and D. lecroyae , the Red Sea species D. fresnelii and the South Pacific species D. pacifica .

Dulichiella cuvettensis is most similar to D. fresnelii and D. pacifica . It differs from both of these species in having two accessory spines on the dactyli of pereopods 5 and 6 and presumably pereopod 7 and in lacking bunches of long, slender setae on any articles of male pereopod 6 and presumably 7. Pereopod 7 is missing in all specimens of D. cuvettensis available to us. The state of the pereopod is presumed based on the character consistency in other species. Dulichiella cuvettensis is further distinguished from D. pacifica by the corner of the male gnathopod 1 palm which is subquadrate in D. cuvettensis and rounded in D. pacifica .

Dulichiella cuvettensis can be distinguished from the Atlantic species, D. appendiculata and D. lecroyae by the longer mandibular palp article 3 and the dactyli of the pereopods which have two accessory spines in D. cuvettensis and only 1 accessory spine each in the two Atlantic species.

Distribution. Mauritius. La Cuvette, Bain Boeuf and Grand Baie, Indian Ocean ( Appadoo & Myers, 2005).