Eremitione clibanaricola ( Shiino, 1933 ) Williams & Boyko & Madad, 2019

Williams, Jason D., Boyko, Christopher B. & Madad, Asma Z., 2019, Branchial parasitic isopods (Crustacea: Isopoda: Bopyridae: Pseudioninae) of hermit crabs (Crustacea: Decapoda: Diogenidae) from the western Pacific, with descriptions of a new genus and three new species, Raffles Bulletin of Zoology 67, pp. 83-118 : 110-112

Eremitione clibanaricola ( Shiino, 1933) , new combination

(Figs. 16F–J, 17)

Pseudione clibanaricola Shiino, 1933: 265–268 , fig. 6 [Tanabe Bay, Japan; infesting Clibanarius bimaculatus (De Haan, 1849) ]; Dollfus in Neveu-Lemaire et al., 1934: 74 [list]; Shiino, 1952: 35, 42 [mention]; Codreanu & Codreanu, 1963: 285 [mention]; Bourdon, 1968: 314 [mention]; Shiino, 1972: 7 [list]; Harada, 1991: 202 [type specimen data]; Trilles, 1999: 326 [mention]; Saito et al., 2000: 37 [list]; Williams & Schuerlein, 2005: 106 [mention]; Markham, 2003: 72 [list]; Boyko & Williams, 2004: 364, 365, 383 [mention]; Saito & Kinoshita, 2004 [list]; Madad, 2008: 2, 4–6, 19, 35–37, 43–46, 48, 49, 51, 62, 63, 82, 83, fig. 7A–E [ Philippines; infesting Calcinus gaimardii (H. Milne Edwards, 1848) and C. minutus Buitendijk, 1937 ]; McDermott et al., 2010: 9 [list].

Ps. clibanaricola, Carayon, 1943: 44 [mention].

Pseudione clibanarticola [sic] Danforth, 1963: 11 [list].

Material examined. Japan: sinistral ♀ lectotype (3.1 mm), 6 sinistral ♀ paralectotypes (2.9–4.3 mm), 1 ♂ paralectotype (0.6 mm) ( SMBL Type #42), all infesting left branchial chambers of Clibanarius bimaculatus (sexes and sizes unknown), coll. S. M. Shiino, Tanabe Bay ; Philippines: 1 sinistral ovigerous ♀ (3.0 mm), 1 ♂ (0.9 mm; lost) ( USNM 1493999 ) from left branchial chamber of ♂ Calcinus gaimardii (2.9 mm SL), host also infested with Bopyrissa marami , new species ( USNM 1493934 ) from right branchial chamber, Puerto Galera, Coco Beach , coll. JDW, 12-15 January 1999 ; 1 sinistral ovigerous ♀ (4.9 mm), 1 ♂ (0.9 mm) ( USNM 1494000 ) from left branchial chamber of ♀ C. gaimardii (3.2 mm SL) Puerto Galera, Coco Beach , coll. JDW, 12-15 January 1999 ; 1 sinistral ovigerous ♀ (4.3 mm), 1 ♂ (1.4 mm) ( USNM 1494001 ) from left branchial chamber of ♀ Calcinus minutus (3.1 mm SL), Batangas, Anilao , coll. JDW, 13 February 1999 ; 1 sinistral ovigerous ♀ (4.2 mm), 1 ♂ (0.9 mm) ( USNM 1494002 ) from left branchial chamber of ♂ C. gaimardii (2.6 mm SL), Puerto Galera, Big Lalaguna Beach , coll. JDW, 28 March 1999 ; 1 sinistral ovigerous ♀ (3.5 mm), 1 ♂ (0.8 mm) ( USNM 1494003 ) from left branchial chamber of ♀ C. gaimardii (2.1 mm SL), Bataan, Morong , coll. JDW, 25 April 1999 ; 1 ovigerous ♀ (4.5 mm), 1 ♂ (1.1 mm) ( USNM 1494004 ) from left branchial chamber of ♂ C. gaimardii (3.0 mm SL), Puerto Galera, Agus Beach , coll. JDW, 18 June 2000 .

Type locality. Tanabe Bay , Japan ( Shiino, 1933) .

Distribution. Tanabe Bay, Japan ( Shiino, 1933); Puerto Galera, Bataan, and Batangas, Philippines ( Madad, 2008; herein).

Hosts. Calcinus gaimardii (H. Milne Edwards, 1848) ( Madad, 2008; herein), C. minutus Buitendijk, 1937 ( Madad, 2008; herein); Clibanarius bimaculatus (De Haan, 1849) ( Shiino, 1933) .

Size range (length). Females to 5.3 mm, males to 1.5 mm ( Shiino, 1933). Mean length of Philippine female specimens was 4.21 ± 0.68 mm and mean maximal width was 2.37 ± 0.42 mm (n=6). Mean length of Philippine male specimens was 1.16 ± 0.25 mm and mean maximal width was 0.46 ± 0.04 mm (n=6).

Remarks. Eremitione clibanaricola , new combination has not been reported subsequent to Shiino’s (1933) original description. One of the female specimens in the type series (SMBL Type #42) is labeled as the lectotype but such a designation was never published by any author; we formally select this specimen as the lectotype herein. Shiino (1933) noted that one of the more important characteristics of this species is the marked asymmetry of the female. Reduced development of the frontal lamina as well as reduction in the coxal plates are also characteristics that distinguish females of E. clibanaricola , new combination from congeneric species ( Fig. 17A ). Females of this species examined in the current study had very short antennae, which did not extend past the margin of their heads. The inner ridge of oostegite 1 of nearly all female specimens had slight digitation, often close to the base of attachment (Fig. 16F, H), which differs from Shiino’s (1933) original description. However, examination of the types of Pseudione clibanaricola confirmed the presence of slight digitation (Fig. 16J) and this character was merely overlooked by Shiino. All female specimens, including the types, lack a palp on the maxilliped (Fig. 16I) and have a barbula represented by a single large lateral digitiform extension and a medial low rounded nub (Fig. 16G), which is consistent with the original description, although Shiino (1933) stated that there were two medial lobes. Uniramous uropods were seen in all of the female specimens examined; however, in certain cases the uropods were proportionally smaller than originally described. Male specimens were consistent with the original description of Pseudione clibanaricola , with eyes absent, a suboval head, and rounded, broad pleopods extending from the ventral surface of pleomeres 1–5 ( Fig. 17B ). One male specimen exhibited coalescing of some pleomeres.

Shiino (1933) reported that E. clibanaricola , new combination was found only in the left branchial chamber of its type host, Clibanarius bimaculatus , in Tanabe Bay, Japan, and this sinistral distortion is consistent with all specimens examined in the present study. Asymmetrione asymmetrica ( Shiino, 1933) is known only from the right chamber of C. bimaculatus ; occasionally this host bears both species of bopyrids simultaneously ( Shiino, 1933). This dual-parasitism and apparent resource partitioning is similar to the occurrence noted in this study of Bopyrissa marami , new species in the right branchial chamber and E. clibanaricola , new combination in the left branchial chamber in one specimen of Calcinus gaimardii .

Ecology. Mean prevalence was 1.03 ± 0.40% over the five collections in which the parasite was found (n=742 total hermits examined). In total, six specimens of Eremitione clibanaricola , new combination. were extracted from hermit crabs collected in the Philippines, most (83.33%) infesting C. gaimardii ( Table 1) but one was found on a female C. minutus .

Figures

Fig. 17.Eremitione clibanaricola (Shiino, 1933), new combination, USNM 1494001. A, female, dorsal view; B, male, dorsal view. Scale bars = 1.0 mm (A); 500 µm (B).