Homologenus namakae Ng, 2016

Ng, Peter K. L., Forges, Bertrand Richer De & Martin, Joel W., 2020, The Homolidae of the Hawaiian Islands, with notes on the taxonomy of Moloha major (Kubo, 1936) (Crustacea: Decapoda: Brachyura), Zootaxa 4809 (2), pp. 306-328 : 323-324

Homologenus namakae Ng, 2016

( Fig. 13 , 14 )

Homologenus namakae Ng, 2016: 48 , figs. 1–3.

Material examined. Hawaiian Islands: Holotype female (14.3 × 12.7 mm) ( SIO C3517 ), station SS-72, 137-DB, south of Kaua‘i , 21º58.13’N 159º16.81’W, 823 m, coll. RV Sea Scope , box dredge, 9 July 1972.— Others : 1 female (13.4 × 11.8 mm) ( USNM 128585 ), Molokai , north coast, 1009.5–1479.5 m, coll. RV Albatross , trawl, 17 April 1902.—1 ovigerous female (14.6 × 12.6 mm) ( USNM 128586 ), French Frigate Shoal , 23º49’30”N 166º25’55”W, 726–757 m, coll. RV Albatross , tangle net, 29 May 1902.— 1 male (carapace partially crushed, length 10.9 mm) ( USNM 128587 ), off Kaua‘i , southeast of Ukula Point, 929–1018.6 m, coll. RV Albatross, trawl, 17 June 1902.

Remarks. Ng (2016) described Homologenus namakae from one female from Kaua‘i but we have since found three lots in the USNM from Hawai‘i that are also referable to this species; they had been previously been identified as H. malayensis Ihle, 1912 . Ng (2016: 52) placed H. namakae in a group of with H. asper Zarenkov, in Zarenkov & Khodkina, 1983 , H. malayensis Ihle, 1912 , H. levii Guinot & Richer de Forges, 1995 , and H. donghaiensis Chen, 1986 ), all of which are distinguished by the absence of a spine at the base of the large anterolateral spine and the presence of only one spine on the distal margin of each P2–P4 merus. Homologenus namakae , however, can be eas- ily distinguished from the other species in this group by the complete absence of a spine or tubercle on the gastric region and having relatively short antennal and subhepatic spines. The male of the species is figured here for the first time ( Fig. 14 C–E). The taxonomy of H. malayensis s. str. was also recently revised by Ng & Richer de Forges (2017) who recognised two allied new species from the South China Sea.

Distribution. Known only from the type locality around Kaua‘i (Ng, 2016).

Figures

FIGURE 13. Homologenus namakae Ng, 2016. A, B, female female (13.4 × 11.8 mm) (USNM 128585); C–E, male (carapace partially crushed, length 10.9 mm) (USNM 128587). A, overall overall dorsal view; B, dorsal view of carapace; C, D, left G1; E, left G2. C–E, same scale.

FIGURE 14. Homologenus namakae Ng, 2016. A, B, ovigerous female (14.6 × 12.6 mm) (USNM 128586); C–E, male (carapace partially crushed, length 10.9 mm) (USNM 128587). A, left P5; B, left P5 propodus and dactylus; C, pleonal somites 4–6; D, pleonal somite 6 and telon; E, left G1. Scales: A, C, D = 1.0 mm; B, E = 0.5 mm.