Nicippe unidentata K.H. Barnard 1932

Nicippe unidentata K.H. Barnard, 1932

(Figure 8)

Nicippe unidentata K.H. Barnard, 1932: p. 133;? Enequist, 1949: 325. (probably Nicippe unidentata = Nicippe tumida Bruzelius, 1859, according to J.L. Barnard, 1959); J.L. Barnard, 1958: 110;? J.L. Barnard, 1959: 38. (probably Nicippe unidentata = Nicippe tumida); Karaman, 1974: 23; Lowry & Bullock, 1976: 124.

? Voss, 1988: 54. (Nicippe? unidentata); Barnard & Karaman, 1991: 578;? Klages, 1991: 51; De Broyer & Jazdzewski, 1993: 82; De Broyer et al., 2007: 179.

Material examined: 1 male, 10 mm, from the type series designated as lectotype herein; paralectotypes: 1 ovigerous female, 11 mm; 1 female, 11 mm; 1 damaged female, approx. 12 mm; 2 males (?), 10 mm; 1 damaged male, approx. 12 mm; all specimens from locus typicus: Schollaert Channel, Palmer Archipelago, 278–500 m, 14 March 1927, The Natural History Museum London, 1936.11.2 1136-1143, Discovery Expedition St. 182.

1 paralectotype, not exactly from type locality, female with setose oostegites, 14 mm (designated herein, illustrated specimen); Schollaert Channel, Palmer Archipelago, 160–335 m, 12 March 1927, The Natural History Museum London, 1936.11.2 1144, Discovery Expedition St. 181, designated as cotype on the museum label.

Description based on male lectotype and illustrated female paralectotype. Head without any trace of eyes or ommatidea; with short rostrum; lateral cephalic lobe acute, with a keel starting at this sharp angle and extending more than half the head length posteriorly; head quadrately lobate posteroventrally. Pereon segments 1–4 subequal in length, segments 5–6 longer, segment 7 longest. Pleon segments 1–2 subequal in length, segment 3 longest. Epimeral plates 1–3 with posteroventral sharp cusps. Urosomite 1 as long as 2–3 combined, with a strong pointed tooth extending beyond the posterior segmental margin; small pointed process ventrally at insertion of uropod 1. Urosomites 2–3 smooth, without dorsal teeth.

Antenna 1 longer than antenna 2; peduncular articles 1–3 relative lengths = 1: 0.6: 0.3; accessory flagellum 3-articulate in male lectotype, with elongate and widened article 1 and 4-articulate in female; flagellum article 1 stouter and longer in male. Antenna 2 peduncular article 3 twice as wide as article 4; articles 4–5 subequal in length. Epistome weakly produced, rounded. Labrum wider than long, medially excavate with right lobe longer than left one. Both mandibles with a sharp incisor with projecting tooth posteriorly; left lacinia mobilis wide, with dentate cutting edge, on the right mandible spine-like; mandibular palp 3-articulate, article 2 longest, about 1.75 x length of article 3, article 2–3 with long setae on ventral margin. Maxilla 1 outer plate with 7 smooth apical spine-teeth, the lateral one strongest and longest; palp 2-articulate, second article expanded distally, with apical row of short spine-like setae; inner plate small with 1 apical seta. Maxilla 2 small, inner lobe slightly shorter than outer, with row of setae on medial margin; both lobes with long apical setation. Maxilliped inner lobes narrow and pointed with long apical setae; outer plate slender, extending up the distal margin of palp article 1, with setae along medial margin; palp long, robust, article 2 longest and widest, densely covered with setae posteromarginally; article 4 slender with serrate inner margin.

Coxal plates all wider than long, not much overlapping. Gnathopod 1 coxa with rounded anterior projecting lobe; basis expanded distally, anterior margin widened and flat, triangular in cross section, posterior margin with groups of long setae; ischium triangular, subequal in length to merus; carpus with wide, rounded ventrally projecting lobe, with long setae posteromarginally and medially; propodus about as wide as carpus, tapering distally, straight palm with long setae; dactylus slender, slightly curved, with one proximal tooth on inner margin. Gnathopod 2 coxa subrectangular; compared to that of gnathopod 1; basis longer, more slender, less expanded; ischium shorter than merus; carpus more slender, but with similar groups of long setae; propodus and dactylus of similar shape but slightly shorter. Pereopods 3–4 similar in shape and length, both with long setation, but pereopod 3 with slightly wider basis to propodus, propodus slightly shortened; coxa 3–4 subequal to coxa 2; basis slender, anterior margin straight, posterior margin weakly convex; ischium small with anteromarginal notch; merus expanded distally, anterodistal angle acutely drawn out; carpus as wide as merus, anterior margin of carpus produced; propodus slender, less than 0.5 x width of carpus; dactylus long, slender and weakly curved. Pereopod 5 much shorter than 6 but of similar shape, pereopod 7 longest, slightly surpassing ends of all uropods. Pereopod 5 coxa bilobate, anterior lobe stronger and slightly longer; basis posterior margin straight and flat, posteroventral corner with short rounded lobe; ischium shortest with anteromarginal notch, merus to propodus relative lengths = 1: 0.7: 0.83; dactylus slender and straight, longer than on pereopods 3–4. Pereopod 6 coxa bilobate, both lobes alike; basis longer compared to pereopod 5; merus to propodus relative lengths = 1: 0.76: 1.22; dactylus as for pereopod 5. Pereopod 7 coxa short, tapering posteriorly; basis anteroproximally widened, posterior margin straight and flat with long setae, posteroventral corner roundly lobate; merus to propodus relative lengths = 1: 1.2: 1.2.

Uropod 1 peduncle slightly shorter than rami, distolateral peduncular tooth very strong; outer ramus somewhat longer than inner ramus, both rami slightly surpassing the uropod 2 apex; rami margins bordered with relatively long spine-like setae, with stout spine at tip of both rami. Uropod 2 of similar shape as uropod 1, but both peduncle and rami shorter than on preceding appendage; distolateral peduncular tooth about half the length of that on uropod 1, situated rather dorsally; rami subequal with long spine-like setae. Uropod 3 peduncle with 3 pointed processes dorsally; outer ramus slightly longer than inner; medial margins of both rami with long setulated setae. Telson deeply cleft (almost down to the base) with straight margins of incision, with a long stout seta proximodorsally and a few laterally on both sides; apex of each telson lobe incised, lateral part of apex slighter longer than medial part.

Remarks. The status of Nicippe unidentata K.H. Barnard, 1932, has never been clear (see synonymy). Much of the taxonomic confusion was due to the fact that K.H. Barnard (1932) gave a very brief description of only 6 lines of text, stating the overall similarity to Nicippe tumida Bruzelius, 1859, but unfortunately, providing no illustrations for comparison. Later descriptions of N. tumida (see synonymy) addressed the possible synonymy, but never resolved the problem. Enequist (1949) considered the south Atlantic N. unidentata to be synonymous with the considered cosmopolitan N. tumida, as he found two forms of this species: one with the typical dorsal bidentate urosomite 1 and one with only a single dorsal tooth. In the meantime collections made during polar ecological surveys (Voss 1988; Klages 1991) were found to contain this pardaliscid, but the specimens could not be identified with certainty. As N. unidentata has never been studied in detail since Barnard’s description, the need for a decision on the validity of the species is long overdue.

After our examination of the type series, we are convinced that N. unidentata is a valid and distinct species. However, the situation of N. tumida seems to be more complicated and this cosmopolitan taxon may yet be a complex of several local (North Atlantic, Mediterranean, north east Pacific, South Africa) species.

Nicippe unidentata differs from this complex by several subtle characters (compare Fig. 9) which are especially well visible in the female paralectotype, the largest specimen collected by K.H. Barnard: the characteristic shape of the mid-dorsal process of urosomite 1, which is large and drawn out into a thin acute process (vs a rather angular process); mandibular palp article 3 is shortened, article 2 is 1.75 x as long as this article (vs 1.18 x); maxilliped article 2 appears to be expanded (vs more slender); pereopod 5–6 coxae are clearly bilobed and excavated ventrally (vs almost straight); pereopod 7 coxa is tapering posteriorly (vs subrectangular shape); the peduncle of uropod 2 has a straight, distolateral tooth (vs a curved, distolateral tooth); uropod 3 peduncle with 3 dorsoapical teeth (vs none) and the telson cleft has straight inner margins of incision (vs sinuous inner margins).