Scolelepis (Scolelepis) kudenovi Hartmann-Schröder,

Choi, Hyun Ki & Yoon, Seong Myeong, 2016, Scolelepis (Scolelepis) kudenovi (Polychaeta: Spionidae) new to Korea, Journal of Species Research 5 (3), pp. 355-358 : 356-358

Scolelepis (Scolelepis) kudenovi Hartmann-Schröder,

1981 ṣÑḇẚṆëƌ갯mǵÑ (ṳAE) Scolelepis (Scolelepis) kudenovi Hartmann­Schröder,

1981: 52, figs. 124-129; Imajima, 1992: 17, figs. 11, 12;

Meissner and Götting 2015: 390, fig. 4.

Material examined. Korea, 5 specimens, Gyema­ri, Hongnong­eup, Yeonggwang­gun , Jeollanam­do (126° 26′14″E, 35°23′27″N), 2 Apr 2015, muddy sand, collect­ ed from intertidal soft­bottoms using a sieve (pore size 0.5 mm) .

Description. Body slender, about 8.0 mm long in incomplete specimens and width about 1.0 mm at anterior region including parapodia.

Prostomium conical­shaped, elongated and tapered anteriorly; caruncle extending to setiger 1 with distinct protuberance posteriorly; 2 pair of eyespots arranged in transverse row. Occipital tentacle absent. Palps paired, reaching to about setigers 10­23. Peristomium distinct from setiger 1, forming lateral wings on each sides ( Fig. 1A, B ).

First setiger without branchiae, but with conical­shaped notopodial and neuropodial presetal lamallae; notopodial lamellae slightly longer than neuropodial ones ( Fig. 1C ).

Branchiae elongate and tapered into pointed tip, presented from setiger 2, and continued until posterior end ( Fig. 1 D­G).

Notopodial postsetal lamellae on anterior and medi­ an setigers partially fused to branchiae; pointed tips of lamellae separated from branchiae. Notopodial postsetal lamellae on posterior setigers almost separated from branchiae, becoming gradually smaller, and elongate ventrally. Notopodial presetal lobes low and rounded. Neuropodial postsetal lamellae low and rounded, divid­ ed into interramal and ventral lamellae from median and posterior setigers; interramal lamellae low and rounded, with elongate tips dorsally, and ventral lamellae increasing transverse length ( Fig. 1 D­G).

Anterior setigers with limbate capillary only, arranged in 2 transverse rows. Notopodial hooded hooks bidentate with open hoods, composed of 2­4 hooks per fascicle, presented on posterior setigers. Notopodial capillary setae slender, presented on posterior setigers. Neuropodial hooded hooks bidentate with open hoods, composed of 5­12 hooks per fascicle, and presented from setigers 30­33. Neuropodial capillary setae slender, presented on setigers bearing neuropodial hooded hooks ( Fig. 1 H­M).

Remarks. The present species, Scolelepis (Scolelepis) kudenovi Hartmann­Schröder, 1981 , has been described from Australian and Japanese waters based on the following distinctive features: the notopodial setae are present on the setiger 1; the occipital tentacle is absent; the branchiae are partially fused to the notopodial postsetal lamellae; the notopodial and neuropodial hooded hooks are bidentate only; the notopodial hooded hooks are present on the posterior setigers ( Hartmann­Schröder, 1981; Imajima, 1992; Meissner and Götting, 2015). In this respect, Korean materials of Scolelepis generally agree well with the previous descriptions of S. (S.) kudenovi ( Hartmann­Schröder, 1981; Imajima, 1992; Meissner and Götting, 2015).

Meissner and Götting (2015) described some differences between Australian and Japanese materials of S. (S.) kudenovi in the morphology of the prostomium and the beginning setigers of the neuropodial and notopodial hooks. Korean materials of the present study are very similar to Japanese materials in these characters. So, it is believed that at least two different regional groups, Australian and Far Eastern groups, are existed in S. (S.) kudenovi : Australian group has anteriorly trifid prostomium (vs. anteriorly long and pointed one in Far Eastern group), the neuropodial hooks beginning from about the setigers 38­44 (vs. from the setigers 26­33 in Far Eastern group), and the notopodial hooks from about the setiger 98 (vs. from the setigers 55­62 in Far Eastern group) ( Imajima, 1992; Meissner and Götting, 2015). However, the taxonomic value of these differences between regional groups are still in need of further detailed study because those can belong to intraspecific variability as mentioned by Meissner and Götting (2015).

Among Scolelepis species reported from East Asia, S. (S.) kudenovi resembles S. (S.) daphoinos Zhou, Ji and Li, 2009 and S. (S.) lefebvrei (Gravier, 1905) in having the setiger 1 with notopodial setae, the partially fused branchiae to the notopodial lamellae, and the absence of the occipital tentacles. However, the former species is easily distinguishable from latter two species by the presence of the indistinct pigment pattern on the dorsum of anterior body (vs. distinct reddish pigment patches in S. (S.) daphoinos ) and the bidentate hooded hooks (vs. unidentate ones in S. (S.) lefebvrei ) ( Imajima, 1992; Zhou et al., 2009).

Habitat. Japanese materials were collected from the subtidal zone (depth 45 m), but Australian materials were distributed in the fine sand of intertidal zone ( Imajima, 1992, Meissner and Götting, 2015). In Korean waters,

our materials were found from the muddy sand of intertidal zone.

Distribution. Australia, Japan, Korea.

Depository. NIBRIV0000325701, NIBRIV0000325702.

Figures

Fig. 1. Scolelepis (Scolelepis) kudenovi Hartmann­Schröder, 1981. A, dorsal view of anterior end; B, lateral view of anterior end; C, anterior view of first setiger; D, anterior view of setiger 12; E, anterior view of setiger 42; F, anterior view of setiger 58; G, anterior view of posterior setiger; H, notopodial hooded hook; I, neuropodial hooded hook; J, neuropodial capillary seta of setiger 12; K, notopodial seta in posterior row of setiger 42; L, neuropodial seta in anterior row of setiger 42; M, neuropodial companion seta of posterior setiger. Scale bars: A, B=0.5 mm, C­G=0.2 mm, H­M=0.05mm.