Lupocyclinae Paulson, 1875

Huang, Yu-Hsuan & Shih, Hsi-Te, 2021, Chthonius rhodochelatus Hadzi 1933, Zoological Studies 60 (60), pp. 1-45 : 11

Subfamily Lupocyclinae Paulson, 1875 Genus Lupocycloporus Alcock, 1899 Lupocycloporus minutus ( Shen, 1937) ( Figs. 3B , 6 )

Neptunus (Lupocycloporus) minutus Shen, 1937: 115 , fig. 10a–b (type locality: Siglap, Singapore).

Portunus minutus – Stephenson 1967: 16, pl. 2 (Indo-West Pacific); Stephenson 1975: 179 (Timor; Sumatra: Aceh); Cariaso and Garcia 1986: 213, fig. 26 ( Philippines).

Portunus (Lupocycloporus) minutus – Serène 1968: 67 (list); Ng et al. 2008: 151 (list).

Lupocycloporus minutus – Sasaki 2019: 9038 (list).

Material examined: Taiwan: 3 males (17.0–17.6 × 9.7–10.1 mm) (NCHUZOOL 16534), Zuoying, Kaohsiung, Jun. 2001; 1 female (17.9 × 10.4 mm), 1 ovig. female (18.9 × 10.6 mm) (NCHUZOOL 16565), Dalinpu, Siaogang, Kaohsiung, Jun. 2001.

Diagnosis: Carapace transversely hexagonal, 1.7 times broader than long. Frontal ridge absent; protogastric, mesogastric, metagastric, cardiac regions each with a pair of faintly granulated ridges; epibranchial regions with a pair of granulated ridges; mesobranchial regions with 2 pairs of granulated ridges ( Fig. 6A ). Front granulated with 4 shallow lobes, lateral 2 broader than median. Supraorbital margins with 2 notches ( Fig. 6A ). Anterolateral margins with 9 teeth, each tooth with posterior margin granulated, teeth 2–4 small and blunt, teeth 5–9 gradually increasing in size, tooth 9 largest ( Fig. 6A ). Chelipeds elongated with surface granulated, merus with 4 spines on inner margin, 2 spines on outer margin; carpus with 2 spines; palm slender with 3–4 spines on dorsal surface, outer surface with 3 granulated ridges, inner surface with 1 granulated ridge. P5 with merus having spine on inner margin; propodus with inner margin smooth. Male pleon with pleomere 6 trapezoidal; telson longer than broad. G1 smooth, distal half slender, bent laterally ( Fig. 6B, C ).

Distribution: East Timor; Philippines; Taiwan; Japan (Ryukyus); Singapore (Siglap); Thailand (eastern side); India (Andaman and Nicobar Is.) ( Sasaki 2019; this study).

Ecological notes: Specimens were collected by trawling at about 30 meters deep.

Remarks: Lupocycloporus minutus ( Shen, 1937) is similar to Luo. innominatus (Rathbun, 1909), but both were described too briefly to distinguish them ( Spiridonov 1999). Spiridonov (1999) found the specimens from Ambon agreed with the characters of “? Neptunus (Lupocycloporus) gracilimanus ” from Andamans (= Luo. innominatus (Rathbun, 1909)) in Alcock (1899: 45), with more prominent median front lobes and without protogastric ridges, differed from Luo. minutus , but it is also necessary to re-examine the type specimens of Luo. minutus . Our specimens agree with the characters of Luo. minutus in the shallow front lobes ( Fig. 6A ; Shen 1937: fig. 10a) and the G1 morphology ( Fig. 6B, C ; Cariaso and Garcia 1986: fig. 26c, d). This identification is also consistent with its distribution, because the type locality of Luo. minutus is Singapore ( Shen 1937), which is closer to Taiwan, compared with Andamans of Luo. innominatus ( Alcock 1899).

Figures

Fig. 3. Species of the family Portunidae. A, Carupa ohashii Takeda, 1993, female (34.9 × 23.1 mm) (NCHUZOOL 16500), Dongsha I.; B, Lupocycloporus minutus (Shen, 1937), male (17.5 × 9.7 mm) (NCHUZOOL 16534), Zuoying, Kaohsiung; C, Lupocyclus inaequalis (Walker, 1887), male (21.6 × 16.3 mm) (NCHUZOOL 16551), Erzihliao Fishing Port, Kaohsiung; D, Lupocyclus tugelae Barnard, 1950, male (17.5 × 13.1 mm) (NCHUZOOL 16560), Erzihliao Fishing Port, Kaohsiung; E, Podophthalmus minabensis Sakai, 1961, male (25.2 × 14.9 mm) (NCHUZOOL 16499), Dalinpu, Siaogang, Kaohsiung; F, Monomia gladiator (Fabricius, 1798), male (53.0 × 31.2 mm) (NCHUZOOL 16506), Erzihliao Fishing Port, Kaohsiung; G, Monomia lucida Koch & Ďuriš, 2018, male (54.8 × 30.7 mm) (NCHUZOOL 16538), Erzihliao Fishing Port, Kaohsiung; H, Xiphonectes tuberculosus (A. Milne-Edwards, 1861), males (24.3 × 14.3 mm) (NCHUZOOL 16530), Zuoying, Kaohsiung.

Fig. 6. Lupocycloporus minutus (Shen, 1937), male (17.5 × 9.7 mm) (NCHUZOOL 16534). A, carapace; B, C, right G1; B, dorsal view; C, ventral view.