Marojejy Cumberlidge, Boyko & Harvey, 2002

Cumberlidge, Neil & Sternberg, Richard V., 2002, The freshwater crabs of Madagascar (Crustacea, Decapoda, Potamoidea), Zoosystema 24 (1), pp. 41-79 : 71

Genus Marojejy Cumberlidge, Boyko & Harvey, 2002

TYPE SPECIES. — Marojejy longichela Cumberlidge, Boyko & Harvey, 2002 .

DIAGNOSIS. — Eyestalks tapering distally, corneas very reduced; merus, carpus, propodus of both chelipeds extremely elongated, ratio total length cheliped p1 (from ischium to dactylus) to cw 2.6 (right), 2.3 (left).

REMARKS

Marojejy can be distinguished from all other genera of Madagascan freshwater crabs by the tapering eyestalk with a reduced cornea, and by the extremely elongated merus of the cheliped. In addition, Marojejy can be further distinguished from the other small long-legged crabs found in Madagascar ( Madagapotamon , Skelosophusa , and Malagasya n. gen.) as follows. The anterior process of the terminal segment of the mandibular palp is bilobed in Marojejy but this process is completely lacking in Madagapotamon , and the flagellum of the exopod of the third maxilliped while reduced (i.e. of medium length) in Marojejy , is virtually absent (a short stub) in Madagapotamon . The terminal segment of the mandibular palp of Skelosophusa is simple, with a small ledge-like anterior process, whereas the terminal segment of the mandibular palp of Marojejy is bilobed with a medium sized, lobelike anterior process. The exorbital and epibranchial teeth are low and blunt in Marojejy , but relatively large and pointed in Malagasya n. gen.; the anterolateral margins of the carapace are granular in Marojejy , but conspicuously toothed in Malagasya n. gen., and the front is wide and moderately deflexed in Marojejy , but narrow and sharply deflexed in Malagasya n. gen. The long, slender walking legs of Marojejy set this genus apart from Hydrothelphusa and Boreas n. gen., which both have walking legs of normal length.