Ancylodactyla, Galil, 2004

Galil, Bella S., 2004, A new deep water leucosiid genus (Crustacea, Decapoda, Brachyura), Zoosystema 26 (3), pp. 495-502 : 496

Genus Ancylodactyla n. gen.

TYPE SPECIES. — Praebebalia elongata Zarenkov, 1969 , by present designation.

ETYMOLOGY. — From the Greek, ankylos, bent, crooked, and dactylos, finger, for the proximally arched cheliped dactyl.

DIAGNOSIS

Carapace subhexagonal, globose, granulate; regions of carapace excluding hepatic region indistinct. Front produced, bilobed, uptilted. Postorbital region concave. Antennula folded diagonally into antennular fossa, basal antennular segment sealing lower portion of fossa. Antenna short, inserted into orbit, between antennular fossa and ventral orbital tooth. Orbital margin bifissured dorsally, V-shaped fossa ventrally, triangulate tooth proximally on ventral margin. Eyes retractible. Anterior margin of efferent branchial channel laminate, projecting, unifissured, visible in dorsal view. External maxillipeds concealing trapezoid buccal opening, granulose; exognath shorter, more slender than endognath; merus nearly as long as ischium.

Anterolateral margin of carapace sinuous, posterolateral margin rounded. Posterior margin prominent, transverse. Intestinal region tumescent.

Chelipeds very long, nearly equal, slender, subcylindrical; longer, more robust, in adult male than in female specimens. Cheliped merus bearing small knob proximally on posterior margin. Propodus somewhat thicker distally; fingers long, their cutting edge unevenly denticulate. Cheliped dactyl of adult male proximally arched. Pereiopods slender, short; dactyls longer than propodi, lanceolate.

Male abdominal sulcus deep, elongate, nearly reaching buccal cavity. Male abdomen with segments 3-6 fused, narrowing distally, basiolaterally inflated, bearing subdistal tooth, telson triangular; its lateral margin bearing medially vertical ridge fitting into suture between thoracic segments 4 and 5. Adult female abdomen with segments 3-6 fused, greatly enlarged, shield-like; telson laciniate. Shaft of male first pleopod flanged on interior margin, elongate, slender, tapering distally. Second male pleopod longer than first pleopod, filiform.

REMARKS

Ancylodactyla n. gen. differs from Praebebalia emend. in having the male abdomen with segments 3-6, rather than 3-5, fused; lateral margins of carapace rounded rather than medially tuberculate, male second pleopod filiform, longer than first pleopod, rather than short and distally scoop-like; and in lacking spines laterally on the posterior margin of the carapace ( Galil 2001). Ancylodactyla n. gen. differs from Randallia s.s. in having the male abdominal somites 3-6 fused, antennular operculum sealing only the lower portion of the antennular aperture, the anterior margin of efferent branchial channel bilobate, and the second male pleopod longer than first pleopod ( Galil 2003).