Limnoria segnoides Menzies, 1957

Min, Ji-Hun Song and Gi-Sik, 2017, New record of limnoriid and asellote species (Crustacea: Malacostraca: Isopoda) from South Korea, Journal of Species Research 6 (3), pp. 237-240 : 238-239

1. Limnoria segnoides Menzies, 1957

‼은ṜAEḎ꼬ƝȒNj (ljḏ) ( Fig. 1 ) Limnoria segnoides Menzies, 1957: 184 , fig. 38; Roman,

1970: 163.

Material examined. South Korea: 2 females, Munseom, Seogwi­dong, Seogwipo­si , Jeju Island (33°13 ʹ 40.26 ʺ N, 126°33 ʹ 59.64 ʺ E); depth 10­15 m; SCUBA diving and rinsing the rhizome of Corallina sp. (red algae); collected by J.­H. Song on September 18, 2015 .

Diagnosis. Female. Body ( Fig. 1A, D ) oblong, approximately 3.1 mm long, almost 3.2 times longer than the greatest width. Body surface covered with thin setae. Coxae of pereionites 2­7, large and well visible dorsally. Pleonite 5 approximately 0.7 times as long as pleotelson, with V­shaped carina and without node or punctum. Pleotelson ( Fig. 1A, D ), followed by a single node and followed posteriorly by longitudinal carinae. Mandible ( Fig. 1B ), lacking palp, replaced by a stout long seta; lacinia mobilis with two serrated setae. Maxilliped ( Fig. 1C ) with clavate­shaped epipod.

Remarks. Limnoria segnoides was described by Menzies (1957) based on specimens collected from Misaki, Japan. All limnorid species have a mandibular palp, except the following four species (lacking palp): L. segnoides ; L. bituberculata Pillai, 1957 ; L. uncapedis Cookson, 1991 ; and L. zinovae ( Kussakin, 1963) . Among these species, L. segnoides is most similar to L. zinovae ( Kussakin, 1963) in external features, especially in structure of pleotelson. However, L. segnoides differs from L. zinovae in having a bifid lacinia mobilis on mandible and a less elevated node on pleotelson. In general, diagnosis of L. segnoides from South Korea agreed well with the original description of Menzies (1957).

Habitat. Habitat information is not available for the type locality. However, the holotype was collected from a coralline algal community at low tide level in Misaki , Japan. The present specimens were also collected from the bottom with red algae ( Corallina sp. ) at a depth of 10­15 m.

World distribution. Japan ( Menzies, 1957), Madagascar ( Roman, 1970), and South Korea (this study).

Deposition. NIBR No. NIBRIV0000470353 and NIBR IV0000470354 (2 females) .

Molecular characters. GenBank accession numbers: KX171203 and KX171204 (2 females).

Figures

Fig. 1. Limnoria segnoides: A, body of female, dorsal view; B, mandible; C, maxilliped; D, body of female, photographs. Scale bars: A, D=1 mm, B, C=0.05 mm.