Flabellamon kanchanaburiens

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

Flabellamon kanchanaburiens e (Naiyanetr, 1992)

(gure 13a–c)

Ranguna kanchanaburiense Naiyanetr, 1978: 84 (nomen nudum).

Potamon kanchanaburiensis Naiyanetr, 1992b: 2 , gure 1A, B; Ng and Naiyantr 1993: 7, gures 1, 34.

HOLOTYPE. ( RMNH D 42352) Sai Sok Waterfall, Amphoe Sai Yok , Changwat Kanchanaburi, 7 March 1976, leg. P. Naiyanetr.

PARATYPES. One, one ( RMNH D 41616) Sai Sok Waterfall, Amphoe Sai Yok , Changwat Kanchanaburi, 19 July 1981, leg. P. Naiyanetr.

Material. One, one ( SMF 24742): Sai Sok Waterfall, Amphoe Sai Yok , Changwat Kanchanaburi: 14ss06¾ 00 ² N 99ss23¾ 00 ² E, 14 April 1974, leg. Warin.

Diagnosis. Carapace smooth, anterolateral margin well developed, serrated with distinct regular teeth, cervical groove deep in the basal part, Postorbital margin distinct, sharp, sinuous, reaching triangular epibranchial tooth and ending below postfrontal lobes; chelipeds distinctly unequal, only large cheliped with ngers slightly gaping when closed, lined with diOEering teeth on cutting edges, surface of chelae rugose, pleon slender triangular.

Terminal joint of rst gonopod cylindrical, slender; lateral margin straight, overlapping zone reaching the dorso-mesial edge. Overlapping zone forming a conical protuberance on outer overlapping margin at half of terminal joint; exible zone strongly elongated, asymmetric with one mesial lobe; subterminal joint elongated, straight, outer margin sinuous, with a dorso-latera l deep groove close to exible zone.

Type locality. Sai Sok Noi Waterfall, Sai Yok district , Kanchanaburi province .

Distribution. Presently known only from the type locality.

Measurements. 47.7: 62.4: 15.4: 8.6 (holotype).

Remarks. The species is well characterized by its rst gonopod morphology which shows no variation within the material examined. Distinct characters of the rst gonopod are the overlapping zone which forms a conical protuberance on the outer overlapping margin and the exible zone, which is strongly elongated and asymmetric, with one mesial lobe. Re-examination of the holotype and the paratypes here shows clearly that the morphology of the second gonopod is congruent to that of Flabellamon turgidula . The fused zone of the terminal tube of the second gonopod turning one and a half times round the axis of the terminal tube, as well as the cross-section of the terminal tube is characteristic. Therefore this species is transferre d to the genus Flabellamon .