A new classification of Callianassidae and related families (Crustacea: Decapoda: Axiidea) derived from a molecular phylogeny with morphological support Author Poore, Gary C. B. Author Dworschak, Peter C. Author Robles, Rafael Author Mantelatto, Fernando L. Author Felder, Darryl L. text Memoirs of Museum Victoria 2019 Mem. Mus. Vic. 2019-12-31 78 73 146 http://dx.doi.org/10.24199/j.mmv.2019.78.05 journal article 10.24199/j.mmv.2019.78.05 1447-2554 12214175 urn:lsid:zoobank.org:pub:263C1363-0ADA-4972-9224-AC690A1FD238 Aqaballianassa gen. nov. http://zoobank.org/urn:lsid:zoobank.org:act:27E2FC97-B393- 48F5-B69F-83AFD8FF49D7 Type species. Callianassa aqabaensis Dworschak, 2003 , by present designation. Diagnosis . Hermaphrodite. Triangular sclerite separate from branchiostegite at anterior end of linea thalassinica . Rostrum obsolete or obtusely triangular, flat, not reaching cornea. Pleomere 1 tergite undivided, or with weak transverse ridge. Pleomere 6 with sublateral ventral sharp ridge, flared posteriorly. Antennular peduncle articles 2 and 3 with single lateral row of 6–10 well-spaced long setae along lower margin. Mandibular molar calcified, swollen projection without sharp edge; incisor with few teeth. Maxilliped 3 merus wider at ischium-merus suture than long. Male major cheliped merus with oblique spine about one third to half-way along lower margin; propodus distal margin with small lateral tooth; dactylus with dense setae along upper margin. Minor cheliped two-thirds width of major cheliped, both flattened. 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, with spiniform setae near anterior and distal margins, or with facial spiniform setae on rib. Uropodal exopod 1.0–1.8 times as long as wide, 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 anterolateral lobe obsolete, undefined; truncate or slightly convex between posterolateral angles, or slightly concave, sometimes with medial spine. Etymology. An alliteration of the name of the type species and Callianassa , type genus of the family. Remarks . The genus is recognisable by the unique triangular sclerite separated by a clear suture or discontinuity from the branchiostegite at the anterior end of the linea thalassinica. All specimens of A. aqabaensis have male and female gonopores, but pleopods 1 and 2 are sexually dimorphic (Dworschak, 2003; Markham and Dworschak, 2005 ). Two species are included besides the type species, A. brevirostris from Thailand and A. lewtonae from Queensland, plus an undescribed species from Papua New Guinea .