Maera octodens Sivaprakasam, 1968

Appadoo, Chandani, Myers, Alan A. & Fagoonee, Indur, 2002, The genera Quadrimaera and Maera (Amphipoda: Gammaridea: Melitidae) from Mauritius, Journal of Natural History 36 (6), pp. 641-673 : 668-670

Maera octodens Sivaprakasam, 1968

(®gure 17) Maera octodens Sivaprakasam, 1968a: 36 , ®gure 2; Surya Rao, 1972: 196; Ledoyer, 1978: 278,

®gure 31; Ledoyer, 1979: 80, ®gure 45; Ledoyer, 1982: 532, ®gure 200; Berents, 1983: 128,

®gure 22; Myers, 1985: 112, ®gure 88.

Material examined

1, from coral rubble, Padina sp. , Pocockiella variegata , sponges and 3 from Valonia sp. and ®brous green alga, 14 May 1998; 1, from Turbinaria ornata , 4, 1, nine juv., from ®lamentous green alga, 4 from Gracilaria salicornia and Pocockiella variegata , 1 from coral rubble and ®brous green alga, 10 September 1998, Balaclava (20ss3.7¾S 57ss30.7¾E).

Description

Male. Length, 3.5 mm. Head with subocular notch, eyes small and subround. Antenna 1 moderately setiferous; peduncle article 2, 1.1 times article 1; article 3, 0.2 times article 2; ¯agellum with 17 articles; accessory ¯agellum three-articulate. Antenna 2 weakly setiferous; article 5, 0.6 times length of article 4; ¯agellum sevenarticulate. Mandible palp, article 2 subequal to 3; article 3 with three terminal setae and two medial setae. Maxilla 1 inner plate with 3 terminal setae. Maxilla 2 inner plate slightly less broad than outer plate and bearing very ®ne setae on inner margin. Gnathopod 1 coxa produced antero-distally and bearing a notch at the posteroventral corner; ischium with a small excavation; carpus globular in shape without sub-distal excavation; palm convex; dactylus ®tting palm. Gnathopod 2 asymmetrical. Larger gnathopod 2 with very large propodus. Carpus reduced; propodus twice as long as broad and robust; palm with seven strong teeth, with setae in the depressions; dactylus broader distally with a curved and pointed tip ®tting a cavity on the inner face of the propodus. Smaller gnathopod 2, carpus elongate, 2.7 times as long as broad; propodus 2.7 times as long as broad; palm oblique bearing a few small robust and ®ne setae. Pereopod 3±4 basis 4.7 times as long as broad; merus and carpus with few robust setae; dactylus not bi®d. Pereopod 5 basis subrectangulate, 2.8 times as long as broad; merus slightly produced distally. Pereopod 6 basis posterior margin weakly toothed and bearing short setae, anterior margin with short robust setae; merus, carpus and propodus bearing short robust and ®ne setae. Pereopod 7 basis 2.3 times as long as broad, posterior margin toothed and bearing short setae. Epimeron 3, with four distinct teeth on posterior margin. Uropod 1 with many robust setae; outer ramus shorter than inner; peduncle subequal to inner ramus. Uropod 2 peduncle and rami with numerous robust setae; rami subequal to each other and to peduncle. Uropod 3 rami ¯attened with strong elongate robust setae; rami twice as long as peduncle. Telson deeply but not fully cleft; lobe apices bi®d and each bearing a very strong robust seta.

Female. Length, 4.7 mm. Gnathopod 1 very similar to that of male. Gnathopod 2, carpus 2.2 times as long as broad; propodus 2.2 times as long as broad; palm oblique, palmar margin with double rows of short robust setae; dactylus normal.

Remarks

M. octodens males are easily recognized by the asymmetrical male gnathopod 2 (either the left or the right can be large), with strongly expanded propodus, and distinctly toothed palm. The very small round eyes also distinguish this species from Maera hamigera (Haswell) .

Type locality. East Coast of India .

Distribution. N.E. Australia, India, Fiji, Madagascar, Marshall Islands, Mauritius.