Corallianassa assimilis (De Man, 1928)

Poore, Gary C. B., 2023, New records and one new species of Callichiridae (Crustacea, Axiidea) from the Indo-West Pacific, with keys to species of Corallianassa, Lepidophthalmus and Neocallichirus, Memoirs of Museum Victoria (Mem. Mus. Vic.) 82, pp. 71-95 : 72-73

Corallianassa assimilis (De Man, 1928)

Figure 1

Callianassa martensi .— De Man, 1888: 482–483, pl. 21 fig. 1 (not Callianassa martensi [ Miers, 1884]).

Callianassa (Callichirus) assimilis De Man, 1928a: 28 , 93, 109

Glypturus assimilis .— Sakai, 1999: 78, fig. 16a–f.— Sakai, 2005: 138–139.— Sakai, 2011: 433.

Callianassa assimilis .— Tudge et al., 2000: 143.

Corallianassa bayeri Kensley, 2001: 328–332 , figs 1, 2.— Sakai, 2011: 424 (type locality, Agat Bay, Guam).

Corallianassa assimilis .— Komai et al., 2015: 15 ff.

Material examined. USA, Mariana Is , Guam , Apra Harbor and Agat Bay, 13.5° N, 144.8° E, 1–12 m, UF 506 , UF 538 , UF 545 , UF 1227 , UF 1301 , UF 1966 , UF 2055 , UF 2133 , UF 2961 , UF 3027 (17 females, 5 ovigerous; 4.1–8.1 mm) .

Diagnosis. Rostrum upturned; carapace anterolateral spines triangular, short. Maxilliped 3 ischium-merus 2.5 times as long as wide; merus mesiodistal margin convex; propodus, free distal margin oblique. Major cheliped ischium lower margin with 2 small distal spines; merus lower margin with row of distally diminishing denticles; palm as long as wide, upper margin obscurely carinate along proximal half. Minor cheliped merus lower margin smooth; palm 1.3 times as long as wide, tapering; fingers longer than palm, straight. Uropodal endopod 2.4 times as long as wide; anterior margin convex over most of length; posterior margin convex; apex narrow, acute, upturned. Uropodal exopod posterior margin slightly concave; proximal article with blunt lobe overlapping endopod. Telson slightly tapering, 1.5 times as wide as long; posterior margin evenly convex; dorsal surface with about 6 pairs of fine setae separated by median gap on transverse ridge.

Distribution. Tropical Northwestern Pacific, Western Coral Triangle ( Indonesia [type locality: Ambon], Guam).

Remarks. Corallianassa assimilis has a more acute uropodal endopod tip than C. martensi but less so than C. lanceolata . Moreover, the endopod has a strong middorsal ridge and an upturned distal tip. The species was described from Ambon, Indonesia, and its accepted synonym, C. bayeri Kensley, 2001 , from Guam. Sakai (2011) treated the two as synonyms of “ Glypturus ” assimilis on one page but also as separate species in two genera. The most convincing of De Man’s (1928) features distinguishing C. assimilis and C. martensi is the shape of the minor cheliped. The palm of the minor cheliped is more barrelshaped than in other species of the genus and its fingers are relatively longer (much longer than the palm).