Epipenaeon latifrons Bourdon, 1979

An, Jianmei, Boyko, Christopher B. & Li, Xinzheng, 2014, Review of the parasitic genus Epipenaeon Nobili, 1906 (Crustacea: Isopoda: Bopyridae), with new records and redescription of four species from China, Journal of Natural History 48 (33 - 34), pp. 2027-2048 : 2040-2044

Epipenaeon latifrons Bourdon, 1979

( Figures 4 , 5 )

Epipenaeon ingens latifrons Bourdon, 1979b: 425 , 429–430, Figure 4 [Northern Territory, Australia, infesting « tiger prawn » (see below). - Bourdon et al. 1981: 497, 498, 500. - Nearhos and Lester 1984: 257, 258 [type material (?), infesting “ Penaeus semiculatus ”, see below]. - Poore et al. 2002: 125.

Epipenaeon latilamellaeous An, 2006: 138 , fig. 70 [ China, infesting P. semisulcatus ].

Material examined

Infesting Fenneropenaeus penicillatus: CIEPE 550303, ♀, CIEPE550304 , ♂, Xiamen , Fujian Province, 118°05’ E, 24°30’ N, 29 March 1955 . CIEPE550305 , ♀ , CIEPE550306 , ♂, Xiamen , Fujian Province, 118°05’ E, 24°30’ N, 29 March 1955 . CIEPE570301 , ♀ , CIEPE570302 , ♂, Xiamen , Fujian Province, 118°05’ E, 24°30’ N, 28 March 1957 . CIEPE570303 , ♀ , CIEPE570304 , ♂, Xiamen , Fujian Province, 118°05’ E, 24°30’ N, 28 March 1957 . CIEPE560326 , 2♀♀, 2♂♂, Guanghai , Guangdong Province, 112°45’ E, 21°56’ N, 26 March 1956 .

Infesting Penaeus semisulcatus: CIEPE 550502, ♀, ♂, Xinying , Hainan Province, 109°30’ E, 19°45’ N, 23 May 1955. CIEPE560302 , 4♀♀, 4♂♂, Suixi fish market, Guangdong Province, 110°28’ E, 21°00’ N, 29 March 1956. CIEPE550102 , ♀, ♂ (for SEM), Shanwei , Guangdong Province, 115°22’ E, 22°45’ N, 7 January 1955. CIEPE560303 , 3♀♀, 2♂♂, Suixi fish market, Guangdong Province, 110°28’ E, 21°00’ N, 29 March 1956. CIEPE541109 , ♀, ♂, Zhapo town, Yanjiang city, Guangdong Province, 115°22’ E, 22°45’ N, 7 January 1955 .

Description of female (CIEPE550303)

Length 20.26 mm, maximal width 15.55 mm across third pereomere, head length 3.11 mm, head width 3.37 mm. All body regions and segments distinct ( Figure 4A, B ).

Head oval, wide frontal lamina extending beyond head; eyes lacking. Pair of small semicircular perforations on boundary between frontal lamina and head ( Figure 4A ). Antennae and antennules of four and three articles, respectively. Maxilliped with long articulated palp ( Figure 4C, D ). Barbula with two pairs of digitate lateral projections on each side, each irregularly tuberculate near centre ( Figure 4E ).

Pereon broadest across third pereomere ( Figure 4A ). Coxal plates well developed on all pereomeres; those on longer side of body larger than those on shorter side. Dorsolateral bosses on first five pereomeres. Brood pouch medially open ( Figure 4B ). First oostegite ( Figure 4F, G ) with rounded posterolateral point, internal ridge bearing many small projections. Pereopods larger posteriorly ( Figure 4H, I ), basis of each pereopod with carina.

Pleon of five pleomeres, fifth pleomere medially incised. Five pairs of biramous pleopods and pair of biramous uropods with surfaces tuberculate, visible in dorsal view ( Figure 4B ).

Description of male (CIEPE407302)

Length 5.66 mm, maximal width across fourth pleomere 2.02 mm, head width 1.07 mm, pleonal length 1.10 mm. All pereon segments distinct, pleomeres fused ( Figures 4J, K , 5A–C ).

Head semicircular, posterior edge curved ( Figure 4J ). Small black eyes on median of head ( Figure 4J ). Antennules of three articles each, setae on distal articles; antennae of five articles each, terminal two articles setose ( Figure 4L ).

Pereomeres subequal in width, midventral projections lacking ( Figures 4K , 5A ). All pereopods with similar sized dactyli, but first three pereopods with rounded carpi, last four pereopods with elongate carpi ( Figure 5A, C ). All carpi, meri with scales and setae on ventral surfaces ( Figure 5B ).

Pleomeres fused with lateral irregular indentations indicating segment traces; pleopods and uropods lacking ( Figure 5C ).

Remarks

Bourdon (1979b) described Epipenaeon ingens latifrons from Australia based on five females (no males) from hosts recorded only as “tiger prawn.” Nearhos and Lester (1984) provided statements that implied they examined the type specimens of E. ingens latifrons , but they listed their material as four females and four males, which is at odds with the number of types given in Bourdon’ s (1979b) description. Bob Lester (pers. comm. to CBB 19 Sept 2013) recalls that the specimens were sent back to Roland Bourdon after examination; their current whereabouts are not known. The identity of the host as given by Bourdon (1979b) is vague, as “tiger prawn” could refer to a variety of penaeids including Marsupenaeus japonicus , Penaeus esculentus , Penaeus monodon , Penaeus semisulcatus , or even Melicertus canaliculatus (Olivier, 1811) , all of which have the word “tiger” in at least one of their common names. Nearhos and Lester (1984) listed the type host for E. ingens latifrons as P. semisulcatus but given the confusion about the number and sex of the types, it is not clear they even examined the actual type material and whether the host was present with the specimens or they inferred host identity from the common name given in Bourdon (1979b).

The present female specimens conform well to the description of Bourdon (1979b), each presenting a wide frontal lamina, coxal plates well developed on the shorter side of the body, a medial incision on the terminal pleomere, and a pair of perforations on the boundary between the frontal lamina and the head. These characters distinguish the taxon from E. ingens (narrow frontal lamina, less developed coxal plates on the shorter side of the body, smaller medial incision on terminal pleomere, front perforations lacking) and we remove E. ingens latifrons from synonymy and consider it as a full species. Characters of the male are provided here for the first time; although Nearhos and Lester (1984) apparently examined males, possibly those collected with type females but not described by Bourdon (1979b), they did not provide any description of male characters.

The first author examined the specimens cited herein for her doctoral work and listed them in her doctoral dissertation (not a published work in the sense of the ICZN 1999) as representing a new species, E. latilamellaeous . Reexamination of these specimens shows that their characters conform to those of E. latifrons Bourdon, 1979 . Therefore, the name E. latilamellaeous , not made available from An (2006), is introduced here in synonymy with E. latifrons and is therefore not an available name from the present work either (ICZN Article 11.6.3). We include the name here to bring attention to its existence and so future authors can avoid confusion by not using it as a name of any species described in this genus or any closely related genera.

Figures

Figure 4. Epipenaeon latifrons Bourdon, 1979, reference female (CIEPE550303) (A–I), reference male (CIEPE550304) (J–L). (A) Dorsal view; (B) Ventral view; (C) Right maxilliped, external view; (D) Palp of right maxilliped; (E) Right side of barbula; (F) Right oostegite 1, external view; (G) Right oostegite 1, internal view; (H) Right pereopod 1; (I) Right pereopod 7; (J) Dorsal view; (K) Ventral view; (L) Left antenna and antennule. Scale: 1 mm for A, B; 0.38 mm for C; 0.18 mm for D; 0.50 mm for E, F, G; 0.14 mm for H; 0.15 mm for I; 0.27 mm for J, K; 0.14 mm for L.

Figure 5. Epipenaeon latifrons Bourdon, 1979, SEM image of male (CIEPE550102) (A–C): (A) Ventral view of first three pairs of pereopods; (B) Right pereopod 7; (C) Ventral view of last two pairs of pereopods and pleon. Scale: 0.20 mm for A, B, C.