Necallianassa, Heard & R.B.Manning, 1998

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 : 95

Necallianassa Heard and Manning, 1998

Necallianassa Heard and Manning, 1998: 883–884. Trypaea .— Sakai, 2011: 385–387 (partim) (not Trypaea Dana, 1952 ).

Type species. Necallianassa berylae Heard and Manning, 1998, by original designation .

Diagnosis. Rostrum obsolete or obtusely triangular, flat, not reaching cornea, or acute, anteriorly directed, as long as eyestalks. Pleomere 1 tergite undivided or with weak transverse step. Antennular peduncle length about 2.5–3 times the width of both eyestalks. Antennal scaphocerite simple, longer than wide, acute. Maxilliped 3 merus wider at ischium-merus suture than long. Male major cheliped merus with prominent truncate hook armed with serrations along lower margin, excavate laterally at base; 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 absent. Uropodal endopod asymmetrical, at least as wide as long, distal margin truncate-convex, at right angles to straight anterior margin, anterior margin with distal spine. Uropodal exopod posterodistal margin with row of 6–8 long blade-like setae proximal to long setae on distal margin.

Remarks. The sharp spine on the anterior margin of the uropodal endopod and usually one or two spines on the lateral margins of the telson uniquely differentiate Necallianassa from all other callianassids ( Heard and Manning, 1998). Necallianassa truncata lacks lateral spines on the telson but the male major cheliped has the same setose propodus and dactylus as N. acanthura (cf. Ngoc-Ho, 2003). The genus was synonymised with the very different Trypaea by Sakai (2011) without explanation.