Paratanais species

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 : 61-62

Key to NZ Paratanais species

(with Atemtanais male)

1. Body slender [6.0–8.8 times ltb]; antennule four or five-articled, [excluding any cap-like segment], with only one terminal aesthetasc; eyes small..............................................................................females, 2

- Body stout [4.2–5.5 times ltb]; antennule with multi-segmented flagellum [four or five segments] bearing numerous aesthetascs; eyes large............................................................................. ..males, 7

2. Pereopods 2–6 carpus spines heavily serrate ( Fig. 36Q ); maxilliped palp article-2 medial seta with sparse but elongate oral pectination ( Fig.36R ); uropod endopod only as long as peduncle.................................... Paratanais caterae

- Pereopods 2–6 carpus spines weakly or moderately serrate ( Fig. 36S ); maxilliped palp article-2 medial seta with short dense oral or aboral serration ( Fig. 36T ); uropod endopod longer than peduncle......................................... 3

3. Antenna article-2 with thorn-like inferior spine or apophysis with terminal seta ( Fig. 36U )............................4

- Antenna article-2 with mid-inferior or inferodistal seta (usually on small apophysis or pedestal [if present]) ( Fig. 36V )...... 5

4. Antennal article-2 inflated, with inferodistal spine; article-3 superior spine relatively short and broad; pereopods 2–3 basis with superior seta (c.f. Fig. 36W ); pereopods 4–6 merus without seta (c.f. Fig. 36X )................................ P. tara

- Antenna article-2 not inflated but with large subdistal apophysis; article-3 spine long and acute; pereopods 2–3 basis with inferior seta ( Fig. 36Y ); pereopods 4–6 merus with seta ( Fig. 36Z ).......................................... P. hamulus (N.B. Penteparatanais may key out here if only with four-articled antennule; see remarks for this species).

5. Antenna article-2 inflated; article-3 superior margin convex; carpus spines of pereopods 4–6 relatively short and stout; uropod exopod one or two-segmented.................................................................... .. P. paraoa

- Antenna article-2 not inflated (subrectangular); article-3 superior margin not strongly convex; uropod exopod one-segmented.....................................................................................................6

6. Cephalothorax only as long as pereonites 1–2 combined; pereopod-1 merus long (three times ltb); uropod exopod longer than peduncle; pereopods 2–3 hardly smaller than pereopod-1; antenna article-2 inferior seta at mid-length ( Fig. 36V ).................................................................................................... P. incomptus

7. Antennule flagellum four-segmented....................................................................... 8

- Antennule flagellum five-segmented (segment-5 small, caplike)................................................. 9

8. Antenna flagellum segment-1 with many aesthetascs, segment-2 longer than succeeding segments; chela strongly curved ( Fig. 31A ), dactylus with one long spine on incisive margin.................................................. .. P.puia

- Antenna flagellum segment-1 with relatively few aesthetascs, segment-2 short; chela not curved, dactylus with one or two peg- like spines on incisive margin............................................................. Atemtanais taikaha

9. Antenna article-2 with inferior apophysis and seta........................................................ P. tara

- Antenna article-2 with sub-distal or inferodistal seta (with or without small apophysis).............................. 10

10. Uropod endopod longer than peduncle; cheliped dactylus with one peg-like spine on incisive margin............ P. paraoa

- Uropod endopod about as long as peduncle; cheliped dactylus with two peg-like spines on incisive margin........ P. caterae

The southeast Australian species Paratanais tanyherpes would key out at couplet 4 with P. tara , but is more elongate (pereonites 4 and 5 longer than broad, both shorter than broad in P. tara ) and has a one-segmented uropod endopod, inter alia. The other three Paratanais species described from the eastern seaboard of Australia, P. maleficus , P. perturbatius , and P. wanga would appear at couplets 6, 6, and 5 respectively but the first (actually a chimaera with P. malignus in Larsen 2001) lacks a sinuate cheliped propodal spine, has a very short antennal article-3 spine, and the antennal article-2 has mid-inferior seta (not shown in Larsen 2001); P. perturbatius (also chimaeric with malignus ) has an inferodistal seta on antennal article-2 as in P. puia but has a shorter cheliped fixed finger and dactylus, and less size-differentiation in pereopods 1–3; P. wanga has a large antenna article-2 seemingly without an inferior seta, and one-segmented uropod endopod inter alia [all observations apart from those on P. wanga are based on examination of type and cited material from the Australian Museum, see below].

Figures

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.