Parahelice pilimana (A. Milne-Edwards, 1873 )

Hsu, Jhih-Wei & Shih, Hsi-Te, 2024, First records of Parahelice K. Sakai, Türkay & Yang, 2006 and Pseudohelice K. Sakai, Türkay & Yang, 2006 from Vanuatu, with description of a new species of Parahelice (Crustacea: Brachyura: Varunidae), Zootaxa 5476 (1), pp. 138-151 : 145-147

Parahelice pilimana (A. Milne-Edwards, 1873)

( Fig. 3 )

Helice pilimana A. Milne-Edwards, 1873: 313 (part), pl. 18(1a) [not pl. 18(1, 1b) = Pse. subquadrata ] (type locality: New Caledonia); Serène 1968: 109 (list).

Pseudohelice (Parahelice) pilimana .— K. Sakai et al. 2006: 50, figs. 65, 71, 73, 82, 83 (part?) ( New Caledonia; Indonesia: Lombok; Maluku; Flores).

Parahelice pilimana .— Ng et al. 2008: 227 (list); Nishigaki et al. 2011: 88, figs. 2, 3 (part) [not fig. 2F = Par. daviei ] (Ishigaki, Japan); Sasaki 2019: 12937; Shih et al. 2020: 255 , figs. 3, 4 (Taiwan); Maenosono et al. 2020: 3, fig. 1C, D.

cytochrome c oxidase subunit I (COI) within and between species of Parahelice and Pseudohelice (see Table 1 and Fig. 5 ). Values of the range are shown in parentheses.

Material examined. 3 males (11.2 × 9.0, 10.0 × 8.1, 6.8 × 5.7 mm), ZRC 2023.0247 , st. VM4, between Rose Point and Nasouli River, Sanma Province, Espiritu Santo Island , Vanuatu, coll. SANTO 2006 Marine Biodiversity Survey, 11 Sep. 2006 .

Diagnosis. Carapace ( Fig. 3A ) quadrate, slightly broader than long, ca. 1.2 times as broad as long; surface convex, irregularly punctate and granulate, with noticeable epigastric groove. Frontal margin slightly concave in both dorsal and anterior views.Anterolateral margin with 3 teeth. Suborbital cristae ( Fig. 3D ) in male heteromorphic, mesial part with 3–6 rounded and 4–6 elongated tubercles, lateral part with 1 elongated, laterally, particularly vertically inflated crest, ending with 2 rounded tubercles. Chelipedal palm ( Fig. 3C ) stout, surface finely punctate; usually unequal in male, distinct patch of setae at base of fingers, mostly expanding onto fixed finger; chelipeds in females usually equal, distinct patch of setae at base of fingers but less than in males. Ambulatory legs broad, anterior margins of meri, carpi, and propodi covered with short setae. G1 ( Fig. 3E–F ) slender, slightly curved towards distal end, tapering; female vulvae sunken in lateral part, with elongate semicircular sternal cover.

Distribution. From southern Ryukyus ( Japan), Pingtung (Taiwan), Lombok, Maluku, Flores (Indonesia), Vanuatu, to New Caledonia (K. Sakai et al. 2006; Shih et al. 2020; Maenosono et al. 2020; Shih et al. 2020; this study).

Remarks. This species can be easily separated from other species in Parahelice by the male suborbital cristae. The lateral part has an elongated, laterally, particularly vertically inflated crest in Par. pilimana ( Fig. 3D ; Shih et al. 2020: fig. 4C) [vs. crest not particularly vertically inflated in other species (K. Sakai et al. 2006: figs. 60–66; Shih et al. 2020: figs. 2C, 6C)]. Parahelice pilimana is a newly recorded species to Vanuatu, within its distributional range in the western Pacific Ocean, from southern Ryukyus to New Caledonia (see above distribution).

Figures

FIGURE 3. Parahelice pilimana (A. Milne-Edwards, 1873). A–F, male (11.2 × 9.0 mm, ZRC 2023.0247). A, dorsal view; B, ventral view; C, outer view of left male cheliped; D, left male suborbital crista; E, F, dorsal view of male right G1.

FIGURE 5. A Bayesian inference (BI) tree for species of Parahelice and Pseudohelice, based on the cytochrome c oxidase subunit I (COI) gene. Probability values at the nodes represent support values for BI and maximum likelihood (ML) analyses. For haplotypes from Vanuatu (shown in bold with “*”) obtained in this study, see Table 1. Other haplotypes from GenBank are shown as the accession numbers.