Takereana, Poore, Gary C. B. & Hurley, Desmond E., 2015

Poore, Gary C. B. & Hurley, Desmond E., 2015, Takereana, a new genus of Idoteidae (Crustacea: Isopoda: Valvifera) from New Zealand, Zootaxa 4057 (4), pp. 590-594 : 591-592

Takereana n. gen.

Type species. Idotea festiva Chilton, 1885 , here designated.

Diagnosis. Body vaulted, deeply longitudinally grooved, head narrower than pereonite 1, body barely widest at pereonite 4. Pleon with 2 fully articulating pleonites, pleonite 3 indicated by suture ventrally and dorsally except in median third; pleotelson apically triangular. Antennule flagellum of 1 short article. Antenna flagellum multiarticulate. Mandible narrow, with obsolete setose molar process without armature, with spine row, asymmetrical lacinia mobilis, and toothed incisor. Maxillule inner lobe with apical setae; outer lobe with 12 apical spiniform setae. Maxilla inner lobe with complex setation, middle and outer lobes with distal rows of numerous denticulate setae. Maxillipedal endite with apical setation; palp operculate, articles 2–3 and 4–5 fused. Coxae 2–7 with well-developed contiguous weakly articulating dorsal coxal plates shielding coxal-basal articulation from dorsal view. Pereopods without spiniform setae on palms of merus, carpus and propodus. Pleopod 1 rami narrower and shorter than those of pleopod 2–5. Male pleopod 2 appendix masculina unknown. Oostegites lamellar, on pereopods 1–5.

Etymology. Epithet chosen by the second author; takere in the Māori language of New Zealand means hull of a canoe, and seabed ( Moorfield 2011). Takereana alludes to both the species’ body shape and to its habitat (feminine).

Remarks. Along with most idoteid genera, Takereana has a multiarticulate antennal flagellum. Takereana , Austridotea Poore, 2001 and Idotea Fabricius, 1798 are the only idoteid genera in which both pleonites 1 and 2 are truly articulating. In all other genera pleonite 2 is variously fused to pleonite 1 and visible only laterally. Takereana differs from both in having an obsolete setose mandibular molar; it is columnar and toothed in Austridotea (original observations on material in Museum Victoria) and Idotea (Poore & Lew Ton 1989: fig. 28). Austridotea , another endemic New Zealand genus, with three species, is the only other idoteid with a uropodal exopod (biramous uropod). Takereana differs from Austridotea in that maxillipedal palp articles 2–3 and 4–5 are fused and operculate whereas in Austridotea the palp is of five free articles or has only articles 4–5 fused. All species of Austridotea are smooth with laterally expanded coxae ( Chadderton et al. 2003), a different habitus from Takereana festiva . Takereana differs from Idotea in having two uropodal rami rather than one, greater fusion of maxillipedal palp articles, lacking spiniform setae on pereopods, and unusual narrow pleopods 1.

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