Caligus undulatus Shen and Li, 1959

Maran, B. A. Venmathi, Ohtsuka, Susumu & Jitchum, Pailin, 2012, Occurrence of Caligid Copepods (Crustacea) in Plankton Samples Collected from Japan and Ŋailand, with the Description of a New Species, Species Diversity 17 (1), pp. 87-95 : 93

Caligus undulatus Shen and Li, 1959

Caligus undulatus Shen and Li, 1959: 12 ; Pillai 1966: 123; 1985: 360; Montú 1982: 329; Venmathi Maran and Ohtsuka 2008: 202.

Material examined.On e adult (KMNH IvR 500,

513), Mukaishima island, the Seto Inland Sea, Hiroshima

Prefecture, Japan, St. 3, 34°37 .1'N , 133°21.2'E, 9 September 2010, plankton net.

Description. F emale. Body (Fig. 6E) 3.46 mm long, excluding caudal setae. Cephalothoracic shield longer than wide, 1.78× 1.11 mm. Fourth pediger 0.17× 0.35 mm and slightly constricted anteriorly. Genital complex longer than wide, 0.78× 0.53 mm. Abdomen long, 0.62× 0.17 mm. Caudal ramus 0.15× 0.06 mm, with 3 long terminal and 3 short subterminal setae.

Remarks.ffi e present female is smaller (3.46 mm) than those in previous reports (4.25–4.29 mm) ( Venmathi Maran and Ohtsuka 2008; Venmathi Maran et al. in preparation). However, the general body structure of this specimen corresponds well to a previous description based on specimens found in plankton samples from o Japan and Korea ( Venmathi Maran and Ohtsuka 2008). Later descriptions of C. undulatus di er from that of the original material from China (cf. Shen and Li 1959) in the form of the genital complex which lacks prominent ridges, but they are similar to material from India ( Pillai 1966), Japan, and Korea ( Venmathi Maran and Ohtsuka 2008; Venmathi Maran et al. in preparation). Caligus undulatus has been found rather frequently in plankton in the world oceans ( Ho and Lin 2004b), and it may have unique aspects to its life history, since its host sh has never been reported.