Flabellamon erewanense ( Naiyanetr, 1992b )

Brandis, Dirk, 2002, On the taxonomic status and biogeography of the Isolapotamidae Bott, 1970 (Decapoda, Brachyura), Journal of Natural History 36 (11), pp. 1291-1339 : 1318-1320

Flabellamon erewanense ( Naiyanetr, 1992b)

(gure 14a–c) Potamon erewanense Naiyanetr, 1992b: 5 , gure 1G, H; Ng and Naiyanetr, 1993: 16, gures 9, 44.

PARATYPES. One, one: ( RMNH D 41619) Kanchanaburi province, Erewan waterfall, Thailand, 25 December 1990, leg Naiyanetr .

Diagnosis. Carapace appears stippled due to numerous stumps of setae, anterolateral margin distinct, serrated with small regular teeth, gastric groove deep, connected with indistinct sinuous cervical groove, postorbital crest sharp, straight, connected with a small epibranchial tooth leading to postfrontal lobes, which are on the same level. Chelipeds slightly unequal, chelae rugose, short, cutting edges of ngers with large teeth. Pleon slender, triangular.

Taxonomy and biogeography of the family Isolapotamidae 1319

Terminal joint of rst gonopod conical, lateral margin straight, overlapping zone facing ventral side. A conical protuberance occurs mesially on outer overlapping margin of terminal joint; exible zone bilobed.

Type locality. Erewan waterfall, Kanchanaburi province.

Distribution. Presently known only from type locality.

Measurements. 30.6: 40.1: 12.3: 15.1 (RMNH D 41619).

Remarks. F. erewanense can be easily characterized by the shape of the rst gonopod terminal joint, which diOEers from all other species included in Flabellamon , because the overlapping zone is in the ventral position. In common with the other species, F. erewanense bears a small mesial protuberance on the outer overlapping margin. Flabellamon erewanense was originally described ( Naiyanetr, 1992b) as a species of Potamon , bearing a distinct and well-developed agellum on the exopod of the third maxilliped ( Naiyanetr, 1992b). Examination of the second gonopod of the paratype shows clearly that this species shows the characteristic torsion of the terminal tube and is here reassigned to the genus Flabellamon .