Rikkarus lea Barnard & Drummond 1978

Rikkarus lea

DESCRIPTION OF MALE (juvenile).—Head about 18 percent of total body length, greatest width about 45 percent of length; rostrum almost reaching apex of article 3 on antenna 1, unconstricted, tapering towards apex, apically rounded. Eyes small, dark, with one layer of clear peripheral ommatidia. Article 1 on peduncle of antenna 1 about 1.5 times as long as wide, twice as wide as article 2, apicoventral margin with 7 or more setules, produced dorsal apex with 3 setules, medial face lacking fuzz; article 2 about 0.3 times as long as article 1, apicoventral lateral face with 2 setae; article 3 slightly overriding article 2 on medial surface; accessory flagellum much shorter than primary flagellum, 3-articulate; primary flagellum as long as peduncle, 4-articulate, basal article elongate, all articles bearing large and numerous aesthetascs. Spine formula on article 4 of antenna 2 = 3–1, set 2 with one accessory setule, spines thin, dorsomedial margin fuzzy but elements very elongate and thick, proximoventral margin with 2–3 penicillate setules, ventral margin with 4 setae in tandem, ventral apex with short spine; article 5 about 0.77 times as long as article 4, facial spine formula = 1, with accessory setule, dorsodistal corner with 2 spinesetae, dorsal margin with one calceolus and 2 weakly developed groups of male setae, ventrodistal apex with one seta and 4 setules, ventral margin naked; flagellum weakly elongate, about 2.4 times as long as articles 4–5 of peduncle together, 10-articulate, segments with 1–3 apparent aesthetascs, no calceoli. Prebuccal complex convex anteriorly, poorly extended forward, epistome and upper lip mostly fused together, ventral margin of upper lip truncate. Palpar hump of mandible medium to large, broad; right incisor tridentate; left bidentate with humps; right lacinia mobilis flabellate, distal branch broad, serrate, face with cusp, proximal branch simple, longer than distal branch; left lacinia mobilis broadly flabellate, with 5 teeth; right rakers 2; left 3 plus one rudimentary; molar formed of weak hump bearing 2 densely spinulose or penicillate spines; left molar with regular spination and penicillate spine; palp stout, article 1 short, article 2 with 3 stout inner distal setae and one wire-like inner basal seta, article 3 about 0.95 times as long as article 2, rounded–transverse apex with 9 spine-setae. Each outer lobe of lower lip with cone, mandibular lobes long, weakly attenuate, apically rounded, inner lobes almost completely fused together (damaged during dissection). Inner plate of maxilla 1 large, linguiform, naked; outer plate with 7 spines; palp reaching apex of outer plate, 1-articulate, bearing 3 apical setae and apicomedial notch. Inner plate of maxilla 2 shorter and broader than outer plate, bearing 3 apical setae; subconical outer plate with one medial, one lateral and 2 apical setae. Inner plate of maxilliped with one apicomedial spine, one apicolateral spine and one thinner midapical spine; outer plate with 3 short medial spines and one elongate (hidden) basomedial spine; palp article 2 sparsely spinose medially, article 3 unprotuberant, lacking facial spine, somewhat slipper-shaped and sparsely spinose medially, dactyl elongate, bearing medium apical nail and adjacent setule plus second setule in notch on inner margin. Coxae 1–3 each with posteroventral cusp and setule near sinus, coxa 1 expanded distally, with concave anterior margin, sharp anterior point above anteroventral bevel (point may be artificial); coxae 2–3 rectangular; long setal formula of coxae 1–4 = 4–4–4–1; coxa 4 quadratiform, posterodorsal excavation medium in size, L-shaped, posterodorsal corner rounded, ratio of width to length = 17:18. Long posterior setae on article 2 of gnathopods 1–2 and pereopods 1–2 = 2–3–4–4, long anteriors = 1 (side)–0–0–0, short anteriors = 1–2–2–1, no others. Gnathopod 2 scarcely larger than gnathopod 1; article 5 very small and triangular; article 6 elongate, palm very oblique, defining hump small to medium defining spine large, dactyl fitting palm, posterior margin of article 6 with one seta; length ratios of articles 5–6 on gnathopods 1–2 = 31:95 and 32:97, width ratios = 20:38 and 21:41. Pereopods 1–2 similar to each other; article 4 with one apicofacial seta, article 5 with 2, largest posterior spine far exceeding apex of article 6, posterior margin of article 5 with 4 other similar but shorter spinesetae laterally, with one setule between spines 3–4, article 6 naked proximally but with highly distad set of spine-setae in formula of 2 + 2 plus one middistal spinule, lateral pair of spine-setae short, medial pair as long as dactyl, latter bearing apical scale but lacking any inner distal setule, notch or medial pluseta. Coxae 5–7 posteroventral setule formula = 1–1–1. Articles 4–5 of pereopods 3–4 thin, facial spines absent, formula of facial ridges on article 2 of pereopods 3–5 = 0–1–1; width ratios of articles 2, 4, 5, 6 of pereopod 3 = 45:18:15:8, of pereopod 4 = 67:23:16:8, of pereopod 5 = 91:13:12:6, length ratios of pereopod 3 = 61:22:28:32, of pereopod 4 = 83:50:57:48, of pereopod 5 = 110:27:21:19; article 2 of pereopod 5 especially large, extending to apex of article 4, posterior margin with 4 small setule acclivities, ventral margin with 2; apex of article 6 finely combed. Epimeron 1 with facial ridge, absent on epimeron 2, each with rounded subquadrate posteroventral corner, weakly convex posterior margins with one setule, epimeron 1 otherwise naked,epimeron 2 with 3 facial setae in tandem horizontally, epimeron 3 with 6 teeth on lower half of posterior margin, upper tooth blunt, others sharp, becoming small and cusp-like ventrally, each with setule or seta in adjacent sinus, epimeron 3 otherwise naked. Urosomites naked, unproduced dorsally. Peduncle ofuropod 1 naked basofacially, lateral apex, medial apex and medial margin with one spine, rami of uropods 1–2 naked dorsally, apices of inner ramus on uropod 1 and both rami of uropod 2 with sharp, attenuate scale and barest indication of completely submerged and fused nail, outer ramus of uropod 1 slightly shortened and thinner than inner ramus, curved, apex simple, blunt, inner rami of uropods 1–2 lacking basomedial setule, peduncle of uropod 2 with 3 dorsal spines, medially with one apical spine, lateral peduncular apices of uropods 1–2 very minutely and weakly combed. Uropod 3 scarcely elongate, peduncle with 3 ventral spines, one dorsolateral spine, one dorsomedial setule; rami submasculine, inner extending to M. 87 on article 1 of outer ramus, with 2 long apical and 2 medial setae, article 2 of outer ramus elongate, 0.57, bearing 2 apical setules, lateral margin of article 1 naked except for 2 apicolateral spines, medial margin with one long seta, medial apex with one long seta, one short spine. Telson elongate, not fully cleft, length–width ratio = 18:13, apices tapering, of medium breadth to narrow, subtruncate, bearing one long spine and one apicolateral setule, dorsal pair of plusetules alike, near middle of lobe, elongate. Small bulbar setules of cuticle extremely sparse, emergent setules very short, scarcely as long as width of pore.

ILLUSTRATIONS.—Lateral view of head drawn from slightly dorsal aspect, dorsal view of head reconstructed; unique juvenile male with small penial processes.

HOLOTYPE.—AM, immature male “a,” 2.29 mm. Unique.

TYPE-LOCALITY.—SBS 3, 23 Jul 1973, off Malabar, New South Wales, Australia, 150°16’ E, 33°58′42” S, 66 m.

MATERIAL.—AM, one sample (1).

DISTRIBUTION.—New South Wales, off Malabar, 66 m.


Japara, new genus

DIAGNOSIS.—Eyes present. Flagella of antennae 1–2 reduced in female. Article 2 of antenna 1 ordinary, ventral setae confined apically. Article 1 of antenna 2 not ensiform; article 3 with 2 setules; facial spines on article 4 in 2 rows; article 5 especially short. Right mandibular incisor with 3 teeth; molar not triturative, medium, elongate, conical, bearing 4 or more splayed, semiarticulate spines, bearing fuzz; palpar hump small. Palp of maxilla 1 uniarticulate; inner plate naked. Setation of maxilla 2 weak. Inner plate of maxillipeds partly fused together, apex of palp article 3 not protuberant, dactyl elongate, apical nail distinct, medium. Gnathopods dissimilar, gnathopod 2 strongly enlarged; article 5 of gnathopod 2 very short, cryptic, elongate on gnathopod 1, with eusirid attachment, palms oblique to transverse to chelate, hands of gnathopods 1–2 rectangular, broadened, poorly setose anteriorly. Article 5 of pereopods 1–2 setose posteroproximally. Article 2 of pereopod 3 of broad form, articles 4–5 of pereopods 3–4 narrow to medium, article 2 of pereopods 3–4 not setose posteriorly; pereopod 5 ordinary, article 2 naked ventrally, article 3 ordinary, dactyl normal. Epimera 1–2 lacking long posterior setae, without midfacial setae above ventral facial ridge; epimeron 3 of rounded classification and lacking long setae. Urosomite 1 generally naked; urosomite 3 without dorsal hook or special process. Peduncle of uropod 1 normally elongate, without apicoventral spike, without special enlarged apicolateral–medial spine, peduncular apices of uropods 1–2 combed, inner ramus of uropod 1 with marginal spines in one row, no rami continuously spinose to apex, inner ramus of uropod 2 ordinary. Uropod 3 small to minute, lacking article 2 of outer ramus, rami minute, shorter than peduncle, extending equally, in female each carrying 1–2 vestigial apical setae. Telson ordinary, with 1–2 apical spines or setae on each lobe plus setules.

DESCRIPTION.—Rostrum small to obsolescent. Fuzz on article 1 of antenna 1 in male present; calceoli on male primary flagellum of antenna 1 present. Calceoli on article 5 of male antenna 2 present; flagellum in male with calceoli. Prebuccal parts strongly extended forward, massive, distinct, both epistome and upper lip prominent. Right lacinia mobilis bifid, flabellate; mandibular palp thin, article 1 elongate, article 2 without outer setae, apex of article 3 oblique. Lower lip lacking cones. Outer plate of maxilla 1 with 7 spines, no spine especially thickened, one attached medially and pointing medially. Inner plates of maxilliped poorly armed, thick. Article 3 of gnathopod 1 elongate. Coxae 2–4 without special anterodorsal humps. Some posterior spines on article 6 of pereopods 1–2 thin and seta-like, others thick and stiff, midapical spine or seta absent. Article 2 of pereopod 5 without facial setae. Peduncle of uropod 1 with dorsolateral spines confined apically, medial spines widely spread; peduncle of uropod 2 with only one medial spine confined apically. Peduncle of uropod 3 lacking extra subapical setae or spines. Telson with pair of midlateral or dorsal setules on each side, highly apical.

TYPE-SPECIES.—Japara papporus, new species (here designated).

COMPOSITION.—Unique.

RELATIONSHIP.—The type-species of this genus has general resemblance to Metaphoxus fultoni (Scott) because of the shape of gnathopod 1; the genus appears close to Metaphoxus because of the uniarticulate palp of maxilla 1, the nontriturative molar, broad article 2 of pereopod 3, unproduced article 3 of the maxillipedal palp and the general appearance of the head, body, coxae, and pereopods. Japara differs from Metaphoxus in the miniaturized rami of uropod 3 and the short, broad inner plates of the maxillipeds. In terms of general knowledge about Phoxocephalidae we suggest that the condition of the maxillipeds represents a primitive state and the condition of the third uropods an advanced state in relation to Metaphoxus. The second maxilla of Metaphoxus, Leptophoxus Sars, and Japara also shares similarities in the numerical reduction of setae.

Japara differs from Kondoleus in the absence of spouts on the maxillipeds, the more elongate dactyl of the maxillipeds, the normally subchelate gnathopod 2, the thin pereopod 4, the much shorter rami of uropod 3 and the absence of long distal setae on uropods 1–2.