Hatschekia cadenati Nunes-Ruivo, 1954

Lee, Soyoung, Lee, Wonchoel & Boxshall, Geoffrey, 2013, Seven new species of Hatschekia Poche, 1902 (Copepoda: Siphonostomatoida: Hatschekiidae) parasitic on fishes of New Caledonia, and a redescription of H. cadenati Nunes-Ruivo, 1954, Zoosystema 35 (3), pp. 377-413 : 406-407

Hatschekia cadenati Nunes-Ruivo, 1954

Hatschekia sp. 1 – Justine et al. 2010a: fig. 1B.

MATERIAL EXAMINED. — 3 ♀♀ from E. cyanopodus [JNC 945A], outer side of Récif Kué , off coast of Nouméa, New Caledonia (22°35’59’’S, 166°32’00’’E), coll. J.-L. Justine on 28.X.2003. Female ( NHMUK 2013.1360 ) dissected on 11 slides. 2 ♀♀ used for SEM ;

12 ♀♀ from Variola albimarginata [JNC1209A], Récif Le Sournois , New Caledonia, coll. J.-L. Justine, 27.VII.2004. ( MABIK CR00179969 - CR00179980 ) ;

5 ♀♀ from V. albimarginata [JNC1247B], Récif Le Sournois , off coast of Nouméa, New Caledonia (22°19’32’’S, 166°27’37’’E), coll. J.-L.Justine, 15.IX.2004. ( NHMUK 2012 . 1332-1336) ;

1 ♀ from V. albimarginata [JNC1353B], Passe de Dumbéa , New Caledonia, coll. J.-L. Justine, 28.IX.2004. (specimen lost) ;

31 ♀♀ from E. coeruleopunctatus [JNC1905], Fausse Passe de Uitoé , New Caledonia, coll. J.-L. Justine, 10.VII.2006. (MNHN-IU-2013-4021) ;

18 ♀♀, 1♂ from E. polyphekadion [JNC1911], Récif Tabou, New Caledonia, coll. J.-L. Justine, 20.VII.2006. ( NHMUK 2012 . 1337-1346) ;

6 ♀♀ from E. polyphekadion [JNC1915], Récif Tabou, New Caledonia, coll. J.-L. Justine, 20.VII.2006. (MNHN- IU-2013-4022) ;

1 ♀, 1♂ from E. fasciatus [JNC1936], Récif To, New Caledonia, coll. J.-L. Justine, 5.IX.2006. ( NHMUK 2012 . 1347-1348) ;

1 ♀ from E. rivulatus [JNC1873], Récif Le Sournois , New Caledonia, coll. J.-L. Justine, 20.VI.2006. ( NHMUK 2012 . 1349) ;

10 ♀♀ from E. maculatus [JNC2157], Off Ever Prosperity, New Caledonia, coll. J.-L. Justine, 17.IV.2007. ( NHMUK 2012 . 1350-1359) ;

DNA-barcode (mtCOI) sequences and traces were submitted to GenBank (accession numbers: JQ 664007 ).

REDESCRIPTION

Female

Total body length 625-880 Μm (n = 12, mean = 712 Μm) excluding caudal rami. Cephalothorax ( Fig. 17A ) elliptical with expanded, rounded lateral margins, slightly shorter than wide (172 × 271 Μm), dorsal surface with distinct chitinous markings in form of “m-shape”, bar in mid-line, without side branches, extending only as far as branched posterior tips of curved lateral bars; lateral bars each with short, anterior side branch near anterolateral angles. Trunk ( Fig. 17A ) longer than wide (620 × 256 Μm), widest at level between third and fourth legs; tapering anteriorly to narrow zone resembling neck region; convex lateral margins converging posteriorly to narrow border with urosome; trunk lacking posterior processes.Urosome excluding caudal ramus shorter than wide (43 × 78 Μm) comprising fused genital complex and abdomen ( Fig. 18E ). Caudal ramus ( Fig. 18E ) elongate, longer than wide (31 × 13 Μm), with six naked setae and one plumose mid-lateral seta. Egg sacs shorter than trunk, each containing two elongate eggs.

Rostrum absent. Antennule ( Fig. 17B ) 4-segmented; length 213 Μm; armature formula: 5, 8, 1, 13 + ae. Antenna ( Fig. 17C ) 3-segmented; proximal segment unarmed, fused with cephalosome; middle segment (basis) swollen and tapering distally, ornamented with surface pits; terminal claw without armature, subdivided by suture; total length 131 Μm; middle segment length 95 Μm; terminal claw length 37 Μm. Parabasal papilla ( Fig. 10A ) four or five thumb-like or oval processes. Oral cone robust. Mandible ( Fig. 17D ) slender, tapering distally, with two small distal teeth. Maxillule ( Fig. 17E ) bilobate; both lobes armed with two sharp tapering processes. Maxilla ( Fig. 17F ) 4-segmented; proximal segment unarmed; second segment swollen with one basal seta; third segment rod-like, elongate, with one distal seta; terminal segment small, with one small seta and bifid claw. Maxilliped absent.

Leg 1 ( Fig. 18A ) biramous; protopod bearing one fine inner spine and one outer seta; exopod indistinctly 2-segmented, exp-1 one outer seta, exp-2 with one distal seta and three inner setae (innermost seta minute); endopod 2-segmented, enp-1 unarmed, enp-2 with two distal setae; protopod length 53 Μm; exopod length 55 Μm; endopod length 21 Μm. Leg 2 ( Fig. 18B ) biramous; protopod bearing one plumose outer seta; exopod 2-segmented, exp-1 with one outer seta, exp-2 with two distal setae (inner seta minute); endopod 2-segmented, enp-1 unarmed, enp-2 with two distal setae; protopod length 75 Μm; exopod length 73 Μm; endopod length 44 Μm. Protopods and rami of legs 1 and 2 ( Fig. 18A, B ) ornamented with crescentic rows of blunt spinules on surface. Intercoxal sclerites of both legs elongated, unornamented and unmodified. Leg 3 ( Fig. 18C ) represented by two simple plumose setae arising from subsurface papilla, at mid-level of trunk. Leg 4 ( Fig. 18D ) one small plumose seta arising from subsurface papilla located laterally at three quarters length of trunk.

REMARKS

Hatschekia cadenati had not been adequately characterized and was in need of redescription according to Jones (1985), however, certain details were apparent from the original description by Nunes-Ruivo (1954) that allowed us to positively identify this species. Leg 1 exhibits an unusual setation feature that is unique in our experience, namely that the exopod carries two large setae set very closely together on the inner margin just distal to the articulation between the first and second segments ( Fig. 18B ). Nunes-Ruivo (1954) figured these setae and our material has two large setae and a minute (and easily-overlooked), vestigial element in the same position. In view of additional similarities in overall body shape, size, form of egg sacs with two eggs, defined urosome and elongate caudal rami, we identify our material as H. cadenati . This material was mistakenly treated as representing an undescribed species by Boxshall (in Justine et al. 2010a). All Hatschekia species recorded from serranid hosts are listed in Table 1 and H. cadenati is now reported from a total of 11 different hosts.

Figures

FIG. 17. — Hatschekia cadenati Nunes-Ruivo, 1954 female: A, habitus, dorsal; B, antennule; C, antenna; D, mandible; E, maxillule; F, maxilla. Scale bars: A, 250 μm; B, C, F, 50 μm; D, E, 25 μm.

FIG. 18. — Hatschekia cadenati Nunes-Ruivo, 1954 female: A, leg 1; B, leg 2; C, leg 3; D, leg 4; E, posterior part of trunk, ventral. Scale bars: A-D, 25 μm; E, 50 μm.

FIG. 10. — Hatschekia cadenati Nunes-Ruivo, 1954: A, cephalothorax, ventral view of anterior region showing parabasal papilla (arrowed). Hatschekia euanus n. sp.; B, rostrum, ventral. Hatschekia fuscoguttatus n. sp.; C, parabasal papilla (arrowed); D, rostrum. SEM micrographs.