Balsscallichirus Sakai, 2011

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 : 108

Balsscallichirus Sakai, 2011

Balsscallichirus Sakai, 2011: 414–415 .— Hyžný, 2016: 43–46.

Tirmizicallichirus Sakai, 2011: 474–475 (type species, Callianassa (Callichirus) masoomi Tirmizi, 1970 , by original designation and monotypy).

Barnardcallichirus Sakai, 2011: 416–417 (type species, Callichirus tenuimanus de Saint Laurent and Le Loeuff, 1979 , by original designation).

Capecalliax Sakai, 2011: 345 (type species, Callianassa pixii Kensley, 1976 , by original designation and monotypy) syn. nov.

Forestcallichirus Sakai, 2011: 426–427 (type species, Callichirus foresti Le Loeuff and Intès, 1974 , by original designation and monotypy) syn. nov.

Type species. Callianassa (Callichirus) balssi Monod, 1933 , by original designation and monotypy.

Diagnosis. Anterior branchiostegal lobe sclerotised, well produced anteriorly beyond junction with oblique branchiostegal ridge with which it articulates by means of a virtual condyle. Rostrum obsolete or obtusely triangular, flat, not reaching cornea. Pleomere 1 tergite divided into 2 sections by unsclerified band; tergite weakly sclerotised, if so only posteriorly; pleura oblique thin rods independent of tergite dorsally, separated by extensive flexible region; sternite a thin transverse plate. Antennular peduncle longer than antennal peduncle. Maxilliped 3 ischium and merus narrow, at least 3 times as long as wide at their articulation; crista dentata absent (or few proximal spines only); propodus longer than wide, lower margin convex or about as wide as long, free distal margin clearly oblique or free distal margin transverse or nearly so. Male major cheliped merus with lower margin almost straight or with denticulate blade, more prominent over proximal half of lower margin or with prominent proximal denticulate blade-like tooth on lower margin. Male minor cheliped much narrower than major, carpus longer than palm, fingers shorter than palm. Pereopod 3 propodus subpentagonal, with strong broadly rounded proximal lobe on lower margin, lower margin straight-concave, lower margin straight or weakly concave or weakly convex. Pereopod 4 subchelate. Male pleopod 1 of 2 articles, article 2 longer than wide, with or without slight apical notch. Male pleopod 2 biramous or uniramous; appendix interna absent. Pleopods 3–5 appendices internae barely emerging from endopod margin. Uropodal endopod with convex anterior margin, acute-rounded apex, straight-slightly curved posterior margin, longer than wide. Telson converging to about half basal width from near anterior width over most of length to rounded posterolateral corners or with convex lateral margins and rounded posterolateral corners, posterior margin trilobed, excavate each side of medial lobe or slightly excavate or obscurely excavate between rounded posterolateral corners, with transverse row of robust setae.

Remarks. Balsscallichirus is best recognised by its very narrow maxilliped 3. Sakai (2011) distinguished Balsscallichirus ( B. balssi , B. guineensis ), Tirmizicallichirus ( T. masoomi ), Barnardcallichirus ( B. tenuimanus , B. gilchristi ) and Forestcallichirus ( F. foresti ) from Podocallichirus ( P. madagassus ) on the basis of male pleopods 1 and 2. The distinction is valid— Podocallichirus is considered here a junior synonym of Lepidophthalmus . He did not compare the new genera with each other or with others. Hyžný (2016) synonymised Tirmizicallichirus and Barnardcallichirus with Balsscallichirus and listed five Recent species and four fossils.

Kensley (1976) recognised that his new species Callianassa pixii belonged in the “subgenus Callichirus ”, likening it to Callianassa guineensis . He was supported by de Saint Laurent and Le Loeuff (1979), who grouped this with four of the species listed above, B. balssi , B. foresti , B. tenuimanus and B. guineensis (as species of Callianassa ), on the similarity of triangular rostrum, rounded posterior border of the telson, pediform maxilliped 3 and reduced male pleopod 2. Sakai (2011) erected another monotypic genus, Capecalliax for C. pixii , this time in the family Anacalliacidae , to which it clearly does not belong. Capecalliax and Forestcallichirus , for C. foresti listed in this group correctly characterised by de Saint Laurent and Le Loeuff (1979) are also synonyms of Balsscallichirus . The exceptionally narrow maxilliped 3 was treated as a symplesiomorphy by the morphological analysis of Robles et al. (in press).

The seven species are known only from around Africa, as far north as Mauritania in the west and Pakistan in the east.