Hyperhalosydna striata ( Kinberg, 1856 ) Oi

Park, Taeseo, Lee, Sang-kyu & Kim, Won, 2016, New record of commensal scale worms, Arctonoe vittata (Grube, 1855) and Hyperhalosydna striata (Kinberg, 1856) (Polychaeta: Polynoidae) from Korean waters, Journal of Species Research 5 (3), pp. 517-529 : 520-526

Hyperhalosydna striata ( Kinberg, 1856) Oi 쟁Ñậūffiẖ갯mǵÑ (ṵAE) ( Figs. 2 , 4 )

Lepidonotus striata Kinberg, 1856: 384 .

Polynoe fulvovittata Grube, 1876: 63 ; 1878: 33, 34, Pl. III, fig. 1.

Polynoe platycirrus McIntosh, 1885: 111 , Pl. III, fig. 4, Pl. XVI, fig. 2, Pl. XIX, fig. 3, Pl. VIIIA, figs. 14 - 15, Pl. IXA, fig. 1; Knox, 1951: 62.

Halosydna carinata Moore, 1903: 417 , Pl. XXIII, figs. 16 - 17.

Hyperhalosydna striata : Augener, 1922: 4; 1927: 105; Fauvel, 1932: 26; 1939: 260; Hartman, 1938: 113; 1954: 622; 1975: 194; Imajima & Hartman, 1964: 21; Uschakov, 1982: 96, Pl. XXV, 1 - 5.

Lucopia magnicirra Pillai, 1965: 117 , figs. 2G - H, 3A - C.

Material examined. 1 ind., Jeju­do, Seogwipo­si, near Beomseom (islet), 25 Feb. 2009, depth 25 m, T Park ( NI

BRIV0000326194 ); 2 inds., Jeju­do, Seogwipo­si, near Supseom (islet), 30 Apr. 2009, depth 10 m , T Park ( NIBR IV0000326198 ), ( NIBRIV0000326201 , associated with eunicid species); 1 ind., Jeju­do, Jeju­si, Udo­myeon (island), Boseopbonguji point, 20 Oct. 2011, depth 22 m , T Park and Y Eun ( NIBRIV0000326196 ); 2 inds., Jeju­do, Seogwipo­si, near Supseom (islet), 30 Oct. 2013, depth 34.5 m , T Park ( NIBRIV0000326199 - 200 ) .

Description. Based on 6 specimens. Body elongated, flattened, tapering anteriorly and posteriorly. Length 30 - 42 mm, widest width 4 - 7 mm including parapodium. Body tinged with reddish­brown pigment on ceratophores, cirrophores, styles of antennae and cirri ( Fig. 2A, E ).

Twenty two pairs of elytra on segment 2, 4, 5, 7, 9, alternate segments to 39, 41, and 42. Elytra large, overlapping medially and posteriorly, covering dorsum. Elytra with five reddish­brown longitudinal stripes and white spot above elytrophore. Surface of elytron smooth except for a band of numerous microtubercles along outer edge ( Fig. 2A, C ).

Prostomium bilobed, wider than long, without cephalic peaks. Two pairs of eyes, anterior eyes large, lying dorsolaterally near widest part of prostomium; posterior eyes smaller, lying near rear of prostomium. Palps long, stout basally, tapering to abruptly tapered tips. Three antennae; median antenna with large cylindrical ceratophore, basally cylindrical style, subterminally swelled and abruptly tapered filiform tip; lateral antennae with ceratophores inserted terminally on prostomium thinner than median ceratophores, styles similar with median style but thinner and shorter ( Fig. 2E ). Everted proboscis dorsally and ventrally with total 18 soft papillae, and two pairs of jaws ( Fig. 2B ).

Tentacular (first) segment achaetous, invisible dorsally. Lateral tentaculophores moderate length, with two pairs of dorsal and ventral tentacular cirri, dorsal tentacular cirri longer than ventral cirri; styles smooth, slender, with slight subterminal swelling and abruptly tapered filiform tip. Facial tubercle small, well developed. Buccal (second) segment without nuchal fold, with first pair of elytra, subbiramous parapodia, noto and neurochaetae. Ventral buccal cirri longer than following ventral cirri ( Fig. 2A, E ).

Parapodia subbiramous. Notopodium small, digitiform, with distal groove on anterodorsal face of large neuropodium. Neuropodium notched dorsally and ventrally with bluntly rounded pre­, postchaetal lobes ( Fig. 2G, I ). Dorsal cirrophores on elytraless segment, large, cylindrical, styles basally cylindrical with slight subterminal swelling and abruptly tapered filiform tips ( Fig. 2E ). Ventral cirri short, subulate. Nephridial papillae well developed from segment 8 ( Fig. 2I ).

Notochaetae very small, often absent, mostly hidden between notopodial lobes or by acicular, slightly curved, with several rows of spines below unidentate tips ( Fig. 2F ). Neurochaetae much larger, numerous, with several rows of spines below bidentate tips( Fig. 2J ).

Pygidium small, with pair of anal cirri similar to dorsal cirri ( Fig. 2H ). Anus dorsally on last 3 - 4 chaetigers ( Fig. 2D ).

Remarks. Genus Hyperhalosydna Augener, 1922 consists of three species; H. striata , H. alleni ( Day, 1934) and H. bicornis Averincev, 1978 . Among these species, only H. striata has been reported from southern part of eastern Asian waters ( Moore, 1903; Okuda, 1936; Uschakov, 1982; Uchida, 1988; 1992; Imajima, 2001) ( Fig. 5 ). Hyperhalosydna striata is easily distinguishable from its congeners by unique striped elytra ( Fig. 2A, C ). Examined specimens agree well with previous redescriptions of Hanley and Burke (1991) and Wehe (2006). The number of elytron pairs on adults of this species reportedly show a considerable variation ( Marenzeller, 1902; Rullier, 1965). Later, Hanley and Burke (1991) and Wehe (2006) confirmed the number of elytron pairs as constant 22. All specimens examined from this study agree with this number.

Previous records of this species make no mention of commensal association except Hanley and Burke (1991). Thirteen individuals were closely related with eunicid polychaetes and this commensal association was confirmed in this study ( Fig. 4A ).

Figures

Fig. 2. Hyperhalosydna striata (Kinberg, 1856), NIBRIV0000326200. A, Anterior end with elytra, dorsal view; B, Proboscis, frontal view; C, Right elytron from segment 11; D, Posterior end, dorsal view; E, Anterior end without elytra, dorsal view (arrow indicate dorsal cirrophore); F, Notopodium with notochaeta (arrow) from segment 14; G, Cirrigerous parapodium from segment 14, anterior view; H, Posterior end, ventral view; I, Posterior segments with nephridial papillae, ventral view; J, Neurochaeta from segment 14. Scale bar:A-E, H=1 mm; F, J=0.05 mm; G=0.3 mm; I=0.2 mm.

Fig. 4.A, Hyperhalosydna striata in a tube of eunicid polychaeta; B, Free­living H. striata.

Fig. 5. Distribution of Arctonoe vittata (Grube, 1855) and Hyperhalosydna striata (Kinberg, 1856) in eastern Asia based on the present study (P) and literatures (1-19). 1: Uschakov (1982), 2: Uchida (1992), 3: Imajima (2001), 4: Uchida (1988), 5: Moore (1903), 6: Okuda (1936), 7: Imajima (2001), 8: Imajima and Hartman(1964); Imajima(2001), 9: Imajima(2001), 10: Okuda (1936), 11 and 12: Imajima(2001), 13: Okuda (1936), 14: Imajima(1988), 15-19: Uschakov (1955).