Rhopalione kali Ahyong & Boyko, 2019

Boyko, Christopher B. & Williams, Jason D., 2024, New records of bopyrid parasites (Crustacea, Isopoda, Epicaridea) of pea crabs (Crustacea, Decapoda, Pinnotheridae) with descriptions of two new species of Rhopalione Pérez, 1921 and a review of the genus, Zoosystema 46 (7), pp. 149-175 : 166-167

Rhopalione kali Ahyong & Boyko, 2019

isopod parasite – Serène 1967: 819 [mention].

Rhopalione sp. – Ahyong & Ng 2005: 124 [mention]. — An et al. 2014: 2, table 1 [list].

Rhopalione kali Ahyong & Boyko, 2019: 284-286 , fig. 1 [ ex Serenotheres besutensis ( Serène, 1967) , Perhentian Besar, South China Sea, east coast of peninsular Malaysia, 05°55’N, 102°45’E), 4 m depth]. — Williams et al. 2023: 533 [list].

DESCRIPTION (modified from Ahyong & Boyko 2019) Female

Body nearly straight, subcircular in outline, wider than long when including coxal plates; all segments distinct. Head subquadrate, separated from pereon, wider than long, anterior and posterior margins convex, lateral margins almost straight; wide frontal lamina. Eyes absent. Antennules of three articles each, antennae of five articles each, both visible dorsally, neither with setae. Maxilliped longer than wide; broad non-articulated palp with short, recurved, digitate apex; plectron short, slender, straight. Barbula with smooth, slender falcate projection and round blunt lobe laterally, shallowly concave medially. Pereon nearly straight. Peremeres dorsally distinct, produced laterally into blunt, rounded lobes; widest at pereomere 4; margins straight or weakly curved, mid-dorsal bosses or projections absent; irregularly-shaped dorsolateral bosses and coxal plates on all seven pereomeres, fusion of dorsolateral bosses and coxal plates in posterior two pereomeres. Oostegites completely enclosing brood pouch, strongly vaulted ventrally, not protruding beyond anterior margins of body, not visible dorsally.Oostegite 1 longer than wide; anterior lobe rounded, with shallow emargination, longer than distal lobe; internal ridge with few irregular slender digitations and rounded lobes; posterior lobe with acute, slightly recurved distal projection on margin. Oostegite 5 posterior margin fringed with setae. Pereopods isomorphic, subchelate. Pleon short, five pleomeres, all dorsally distinct, each with lateral plates produced into slender, distally rounded lobes, similar in size and shape to corresponding five pairs of biramous pleopods. Uniramous uropods similar in size and shape to pleopods and adjacent lateral plates of pleomere 5.

Male

Body elongate, fusiform, slightly curved, length 2.2 × width; all segments distinct. Head transversely ovate in dorsal view, longer than pereomere 1; anterior margin broadly curved, almost straight medially; posterior margin broadly curved; eyes present but weakly pigmented. Antennules of three articles each, antennae of five articles each, both with terminal setae. Pereomeres 1-7 subequal in length, lateral margins rounded, posterior margins straight or at most weakly sinuous; pereomere 1 narrower than pereomere 2; pereomeres 2-4, 6, 7 subequal in width, narrower than pereomere 5; midventral projections absent. Pereopods isomorphic in size and shape, subchelate. Pleon broadly tapering to rounded outline; pleomeres distinct, distal margins produced as slender tapering lobes, posteriorly recurved, apices blunt; pleopods 1-5 bulbous, uniramous. Pleotelson deeply bifurcate posteriorly.

REMARK

Only the type material of R. kali is known.