Biffarius Manning and Felder, 1991

Poore, Gary C. B., Dworschak, Peter C., Robles, Rafael, Mantelatto, Fernando L. & Felder, Darryl L., 2019, A new classification of Callianassidae and related families (Crustacea: Decapoda: Axiidea) derived from a molecular phylogeny with morphological support, Memoirs of Museum Victoria (Mem. Mus. Vic.) 78, pp. 73-146 : 91

Biffarius Manning and Felder, 1991

Biffarius Manning and Felder, 1991: 769–771 .— Poore, 2004: 181 (partim).

Trypaea .— Sakai, 2011: 385–387 (partim; not Trypaea Dana, 1952 ).

Type species. Callianassa biformis Biffar, 1971 , by original designation.

Diagnosis. Rostrum obsolete or obtusely triangular, flat, not reaching cornea. Pleomere 1 tergite undivided or with weak transverse ridge. Antennular peduncle exceeded by most to all of antennal peduncular article 5; articles 2 and 3 with single lateral row of 6–10 well-spaced long setae along the lower margin. Maxilliped 3 merus wider at ischium-merus suture than long; crista dentata absent (or few proximal spines only). Male major cheliped merus with prominent truncate hook armed with serrations along lower margin, excavate laterally at base; upper margins of ischium and merus, and lower margins of merus and carpus beaded, with dense row of long fine setae; propodus distal margin with deep notch at base of fixed finger. Pereopod 3 propodus rectangular, lower margin deeply convex, leading to broadly rounded free proximal lobe. Male pleopod 2 present or absent. Uropodal endopod ovoid, usually longer than wide, anterior margin straight or slightly convex, posterodistal margin evenly convex. Uropodal exopod distal margin clearly differentiated from anterior margin, anterodistal corner right-angled, posterodistal margin with row of 6–8 long blade-like setae proximal to long setae on distal margin. Telson longer than wide, tapering evenly from near base; anterolateral lobe defined posteriorly by short transverse slit; transverse ridge with only fine setae; truncate or slightly convex between posterolateral angles.

Remarks. Biffarius has been widely misused by several authors, with up to a dozen species allocated to it, possibly because it was a genus of last resort in Poore’s (1994) key. In fact, the type species shares with one other species, B. limosus , and possibly B. delicatulus , a long antennal peduncle and the lower margins of the major cheliped merus and carpus being beaded and with a dense row of long fine setae. Biffarius biformis occurs from the North Atlantic to Caribbean waters, B. delicatulus occurs in the South Atlantic and B. limosus is known from south-eastern Australia, a somewhat enigmatic generic distribution.