Paratanais puia, Bird & Bamber, 2013

BIRD, GRAHAM J. & BAMBER, ROGER N., 2013, New littoral, shelf, and bathyal Paratanaidae (Crustacea: Peracarida: Tanaidacea) from New Zealand, with descriptions of three new genera, Zootaxa 3676 (1), pp. 1-71 : 46-53

Paratanais puia sp. nov.

Figures 27– 31 , 36S , A’

Material examined. Holotype: one ovigerous ♀ CR.012175. Stn O. 608/BS.862, immediately outside entrance to Whangaroa Harbour, Northland, 25 m, shell & bryozoans, 35.0058˚S, 173.7617˚E, 26 January 1981, RV Tangaroa .

Allotype: one swimming ♂ CR.23502; details as for holotype.

Paratypes: one manca-III CR.012174; two manca-II, one manca-III, seven non-ov. ♀♀ (one partially dissected CR.23503/1), two preparatory ♂♂ (?), one swimming ♂ (partially dissected on microslide CR.23501/2), CR.23501; details as for holotype.

Diagnosis. Female: with pleon longer than pereonites 5–6 combined. Antennule without cap-like terminal segment. Antenna article-2 weakly expanded, with small pedestal-based inferodistal seta, with small lateral seta; article-3 superior spine acute. Mandible lacinia mobilis with crenulated distal margin. Maxilliped palp article-2 with unspecialised serrulate medial seta; endite with rounded distal spines. Cheliped basis longer than broad; palm with sinuate spine dactylus; dactylus without inferior peg-like spines. Pereopod-1 basis with superior seta: merus 2.5 times ltb. Pereopods 2–3 basis with superior seta. Pereopods 4–6 merus without seta; carpus spines well developed, finely serrate. Uropod shorter than pleotelson, exopod one-segmented, as long as peduncle; endopod two-segmented.

without terminal cap-like segment; peduncle article-1 1.5 times ltb; flagellum segment-1 with dense brush of aesthetascs (ca. 20); segment-2 longer than segments 3–4 combined. Cheliped fixed finger incisive margin weakly dentate-serrate; dactylus with peg-like spine. Uropod endopod two-segmented.

Etymology. From Te reo Maori puia , ‘a tuft’, alluding to the male antennule; noun in apposition.

Description. Female: Habitus ( Fig. 27A, C ) slender, 8.0–8.8 times ltb (stretched-relaxed condition; estimated 7.0–7.5 times ltb contracted); length 1.0– 2.9 mm. Cephalothorax ( Fig. 27B ) 1.3–1.4 times ltb, longer than pereonites 1–2 combined (assumed contracted state). Pereon typical, pereonite-1 0.4 times as long as broad; pereonites 4–5 longest, equally long. Pleon 1.3–1.4 times ltb. Pleotelson ( Fig. 27D ) as long as pleonites 4–5 combined, with weakly produced apex.

Antennule ( Fig. 27E ) five times ltb and only 0.75 times as long as cephalothorax; article-1 half of total length; article-2 distolateral seta almost as long as article-4; article-5 indistinct. Antenna ( Figs 27F , 36 A’) article-2 slightly wider distally, superodistal seta as long as article-3.

Labrum ( Fig. 28A ) typical. Mandibles ( Fig. 28B–C ) left molar with six or seven spines; right incisor weakly bifid. Labium ( Fig. 28D ) typical of genus. Maxillule and maxilla (not figured), typical. Maxilliped ( Fig. 28E–F ) bases with setae reaching distal of endite; endite spines relatively large. Epignath not observed.

Cheliped ( Fig. 28G ) basis 1.6 times ltb, posterior lobe smaller than anterior; chela slightly longer than carpus, propodus 2.3 times ltb, palm medial comb with two spines; fixed finger 0.36 times length of propodus; dactylus with two peg-like spines.

Pereopod-1 (Fig. 29A) basis 3.6 times ltb; merus longer than carpus, 2.5 times ltb, with two small superodistal setae and inferior seta; carpus 2.2 times ltb, with four distal setae; propodus nearly five times ltb; dactylus-unguis combined just shorter than propodus. Pereopod-2 (Fig. 29B) 0.7 times length of pereopod-1; basis 2.5 times ltb; merus about as long as broad, with inferodistal spine and seta; carpus subovate; propodus as long as merus and carpus, with one superodistal seta; dactylus-unguis combined 0.8 times length of propodus. Pereopod-3 (Figs 29C, 36S) similar to pereopod-2 but slightly shorter.

Pereopod-4 (Fig. 29D–G) basis stout, 2.1 times ltb, with two inferior PSS; merus with spinulate inferior margin; and carpus slightly longer than merus; propodus slightly longer than carpus, superodistal spine shorter than dactylus. Pereopod-5 (Fig. 29H) similar to pereopod-4. Pereopod-6 (Fig. 29J, 36S) typical, similar to pereopod-5 but basis with one PPS. Pleopod (not figured) similar to that of P. paraoa .

Uropod ( Fig. 27G ) peduncle as long as broad; exopod one-segmented as long as peduncle; endopod twosegmented, 1.7 times longer than peduncle, with five terminal setae.

Manca-II: length 0.75–0.80 mm.

Manca-III: length 1.11 mm.

Male: Habitus (Fig. 30A) typically dimorphic, similar to that of P. paraoa , 4.6 times ltb; length 1.4–1.5 mm. Cephalothorax flask-shaped, as long as pereonites 1–4, rostrum spatulate; eyes just over 0.3 times as long as cephalothorax. Pereon 35 % of body length, all pereonites less than a third as long as broad, but pereonites 4–5 longer than pereonites 1–3. Pleon 28% of body length, as long as pereonites 3–6 combined; pleonites shorter than pereonites 4–5. Pleotelson (Fig. 30B) nearly three times wider than long, with small rounded apical process bordered by two setae.

Antennule (Fig. 30C) as long as cephalothorax, peduncle article-1 very stout, about 38% of total length; article- 2 with lateral seta and three PSS; article-3 short, overhanging following flagellar segment, with two superior setae; flagellar segment-1 very short, segments 1–3 with inferior bundle of aesthetascs (ca. 25–30, eight, and five, respectively), segment-4 with one large stiff distal seta, two short stiff setae, and one long simple seta and aesthetasc. Antenna (not figured) similar to female but article-3 less expanded, with superior stiff seta, article-4 more slender, with medial PSS and long distal seta; article-5 more slender.

Mouthparts: reduced (maxilliped present), typical of genus.

Cheliped ( Fig. 31A–C ) similar to that of P. paraoa but propodus (palm and fixed finger) with more strongly curved long axis (concave inferior margin), and medial comb with nine spines; fixed finger with dentate-serrate incisive margin; dactylus with sinuous inferior margin with proximal serration, and one long lanceolate seta on incisive margin.

Pereopod-1 ( Fig. 31D ) similar to that of P. paraoa but merus, carpus and propodus all longer; merus naked. Pereopod-2 ( Fig. 31E ) similar to that of P. paraoa female but merus slightly longer and propodus inferodistal seta

Pereopod-4 and pereopod-5 ( Fig. 31F ) similar to those of P. paraoa . Pereopod-6 ( Fig. 31G ) similar to pereopod-5 but propodus without superior PSS, with three superodistal serrate spines and inferior margin heavily setulated.

Pleopod similar to that of female but exopod and endopod setae proportionately longer.

Uropod (Fig. 30D) longer than pleotelson; peduncle as long as broad; exopod one-segmented, not quite reaching endopod segment-1; endopod two-segmented, segment-1 as long as peduncle, segment-2 shorter than segment-1, with five simple setae (one very long) and at least one PSS.

Distribution and ecology. Recorded from one locality in northern New Zealand waters, in sublittoral (25 m) shells/bryozoans outside Whangaroa Harbour.

Remarks. Overall, this taxon is very similar to Paratanais paraoa and P. incomptus . It differs from P. paraoa in being more gracile, having a less expanded antenna article-2, and the pereopodal spines tend to be longer. There is a greater disparity in size of pereopods 1–3 than in P. incomptus . The male of P. puia sp.nov. is very similar to that of P. paraoa but is distinguishable by the denser tuft of aesthetascs on the first flagellar segment, more aesthetascs on segments 2–3, a proportionately longer flagellar segment-2, and more bent cheliped chela. With respect to the male antennule, it is very similar to P. clarkae Bird & Bamber, 2000 that also has very stout peduncular articles (N.B. it is presumed that in that species, the tuft of aesthetascs illustrated as being attached to the peduncle article-3 is in fact on flagellum article-1). The male cheliped also approaches that of the Australian P. wanga Bamber, 2008 in shape but has fewer spines in the propodal comb.

It is conceivable that the trio incomptus-paraoa-puia are actually one complex species ‘ paraoa -group’, paraoa-puia representing a habitat-determined cline (with puia in coarse subtidal sediment), and incomptusparaoa a bathymetric series. Ideally, genetic studies would be needed to resolve these taxa fully.

Figures

FIGURE 27. Paratanais puia sp. nov. Holotype female [CR.12175]: A habitus; B cephalothorax, distal. Paratype non-ov.

FIGURE 28. Paratanais puia sp. nov. Paratype non-ovigerous female [CR.23502/1]: A labrum; B–C left and right mandibles, respectively; D labium; E maxilliped (palps omitted); F maxilliped palp; G cheliped. Scale bar: 0.25 mm.

FIGURE 31. Paratanais puia sp. nov. Male [CR.23502 and CR.23503/2]. A cheliped [right]; B cheliped propodus medial

FIGURE 36. A Metatanais sp. antennule, lateral; B Metatanais sp. uropod; C Xeplenois pleon-pleotelson, dorsal and lateral (pleopod & setae omitted), after Bamber 2005; D Penteparatanais pereopod-4 carpus; E Paratanais hamulus pereopod- 5carpus; F Acallocheirus pereopod-2 carpal spines; G P. incomptus pereopod-2 carpal spines; H Aparatanais timutimu maxilliped palp article-2 spine; J A. timutimu cheliped kukri spine: K A. timutimu uropod; L Paratanais caterae cheliped spine; M P. puia uropod; N P.hamulus antenna article-3. O Atemtanais antenna article-3, after Bird 2011; P Atemtanais pereopod-2 carpal spines, after Bird 2011; Q Paratanais caterae pereopod carpal spines; R P.caterae maxilliped palp article-2 spine; S P.