Waematau muriwhenua Duncan, 1994

Ball, P., Webber, W. Richard & Shepherd, Lara D., 2017, New species and phylogeny of landhoppers in the genus Waematau Duncan, 1994 (Crustacea: Amphipoda: Talitridae) from northern New Zealand, Zootaxa 4306 (2), pp. 151-207 : 165-173

publication ID	https://doi.org/ 10.11646/zootaxa.4306.2.1
publication LSID	lsid:zoobank.org:pub:1995C97D-AD54-4CB2-A13F-4C62083FF052
DOI	https://doi.org/10.5281/zenodo.5998958
persistent identifier	https://treatment.plazi.org/id/03B987D8-936E-4072-89E5-FDE2FADA0307
treatment provided by	Plazi
scientific name	Waematau muriwhenua Duncan, 1994
status

Treatment

( FigS 9–14 View FIGURE 9 View FIGURE 10 View FIGURE 11 View FIGURE 12 View FIGURE 13 View FIGURE 14 )

Material examined. Type material. Holotype: male ( CMNZ 2017.18.1), 5 km SoutheaSt of Unuwhao , Northland, New Zealand , coll. WiSe K.A.J., 24 November 1967. Allotype: female ( CMNZ 2017.18.2), 5 km SoutheaSt of Unuwhao , Northland, New Zealand , coll. WiSe K.A.J., 24 November 1967. Other material examined: 5 maleS, 4 femaleS (MNZ CR. 022709), Unuwhao (A); 1 female (MNZ CR.023881), Unuwhao (A) ; 1 male, 1 female (MNZ CR.023882), North Cape ; 3 maleS, 3 femaleS (MNZ CR.023883), SpiritS Bay (B); 3 maleS, 2 femaleS (MNZ CR.023884), Haupatoto ; 1 female (MNZ CR.023885), Kohuroa (A); 2 maleS, 1 female (MNZ CR.023886), Kohuroa (A) ; 1 female (MNZ CR.023887), Radar BuSh ; 1 female (MNZ CR.023888), Unuwhao (A) ; 1 male, 2 femaleS (MNZ CR.023889), Radar BuSh ; 1 female (MNZ CR.023890), Unuwhao (A) ; 1 male (MNZ CR.023891), Radar BuSh ; 1 female (MNZ CR.023892), Unuwhao (A); 2 femaleS (MNZ CR.023893), Radar BuSh; 3 maleS, 2 femaleS (MNZ CR.023894), Unuwhao (A) ; 1 male (MNZ CR.023921), Unuwhao (A).

Diagnosis. Large (body length 11–17 mm), Sexually dimorphic. Eye large, approximately one third head length. Antenna 2 aS long aS head and firSt 5–6 pereoniteS. Maxilliped outer plate not arcuate or diStally acute. Gnathopod 1 propoduS Subchelate in both SexeS; gnathopod 2 propoduS mitten-Shaped in femaleS, Strongly Subchelate in maleS. PleopodS 1 and 2 well developed, biramouS; pleopod 3 reduced, biramouS, but rami minute. Uropod 1 diStolateral robuSt Seta approximately 0.3 timeS length of outer ramuS; outer ramuS with no dorSal robuSt Setae, inner ramuS with dorSal robuSt Setae. Uropod 2 peduncle with characteriStic diagonal row of cloSe-Set robuSt Setae on meSial margin and face; rami with dorSal robuSt Setae. Uropod 3 peduncle laminate, ramuS 0.5–0.6 timeS length of peduncle, with robuSt Setae. TelSon plate-like, longer than broad, with robuSt Setae.

Description. AdultS ( Fig. 9 View FIGURE 9 ) 11–17 mm long. Sexual dimorphiSm apparent at 9–10 mm. Head Slightly longer than pereonite 1. Eye large, approximately one third head length.

Antenna 1 ( Fig. 9 View FIGURE 9 ) extending to leSS than half way along peduncle article 5 of antenna 2; article 3 of peduncle Subequal in length to article 2, narrower; flagellum conSiSting of 6–8 articleS, geniculate near baSe. Antenna 2 ( Fig. 9 View FIGURE 9 ) aS long aS head and firSt 5–6 pereoniteS; article 4 of peduncle Slightly broadening diStally, article 5 of peduncle approximately 1.4 timeS longer than article 4; flagellum 1.3–1.4 timeS longer than peduncle, conSiSting of 17–29 articleS.

Upper lip ( Fig. 10 View FIGURE 10 ) apical margin rounded and SetoSe. Mandible ( Fig. 10 View FIGURE 10 ) left lacinia mobiliS 4-dentate. Lower lip ( Fig. 10 View FIGURE 10 ) inner lobeS well developed, SetoSe. Maxilla 1 ( Fig. 10 View FIGURE 10 ) inner plate Slender, Shorter than outer plate, with two apical plumoSe Setae; outer plate broad with 9 apical Serrate robuSt Setae, outer margin with veStigial palp. Maxilla 2 ( Fig. 10 View FIGURE 10 ) inner plate Slightly Shorter than outer, apical margin with many curved robuSt Setae, plumoSe Seta on inner margin; outer plate apex with many Slender, curved robuSt Setae. Maxilliped ( Fig. 10 View FIGURE 10 ) outer plate broad, not arcuate or diStally acute; palp article 2 with well-developed Seta-covered diStomedial lobe, article 4 viSible but very reduced and button-like.

Gnathopod 1 ( Fig. 11 View FIGURE 11 ) Sexually dimorphic. FemaleS: coxa, deeper than wide, ventral margin with robuSt Setae; baSiS hardly narrowing proximally along poSterior margin; iSchium Short; meruS poSterodiStal margin produced into a Small lobe covered in palmate Setae; carpuS with lobe covered in palmate Setae poSterodiStally; propoduS 0.6–0.7 timeS length of carpuS, Slightly expanded poSterodiStally into a lobe covered in palmate Setae; dactyluS Slightly Shorter than or Subequal to palm, Subchelate. MaleS: Similar to femaleS except baSiS narrowing Significantly along proximal poSterior margin; meruS poSterodiStal margin produced into a large lobe covered in palmate Setae; propoduS greatly expanded poSterodiStally into a lobe covered in palmate Setae; dactyluS conSiderably Shorter than palm.

Gnathopod 2 ( FigS 11 View FIGURE 11 , 12 View FIGURE 12 ) Strongly Sexually dimorphic. FemaleS: coxa Slightly deeper than wide, anterodiStal corner rounded, ventral margin convex with Small robuSt Setae, poSterior margin with Small Subacute proceSS; baSiS narrowing anteroproximally; iSchium weakly broadening diStally; meruS Slightly Shorter than iSchium, produced poSterodiStally into a lobe covered in palmate Setae; carpuS elongate with lobe covered in palmate Setae poSterodiStally; propoduS mitten-Shaped, Subequal in length to carpuS, broadening diStally, lobe apically rounded; dactyluS Short. MaleS: baSiS narrowing poSteroproximally; iSchium Significantly broadening diStally; meruS and carpuS Small; propoduS Strongly Subchelate, Subtriangular to elliptic, palm convex, palm margin with row of Setae of varying lengthS on each Side; dactyluS diStally attenuated.

Pereopod 3 ( Fig. 12 View FIGURE 12 ) coxa anterior margin nearly Straight, ventral margin with Short robuSt Setae, poSterior margin with Subacute proceSS; baSiS broadening diStally; iSchium Short; meruS broadening diStally; carpuS approximately 0.8 timeS length of meruS; propoduS Slender, Subequal to or Slightly longer than carpuS.

Pereopod 4 ( Fig. 12 View FIGURE 12 ) Shorter than 3; coxa ventral margin nearly Straight to Slightly convex with Short robuSt Setae, anterodiStal corner rounded and obtuSe, poSterodiStal corner a Sharper right angle, poSterior margin with Subacute proceSS; baSiS broadening diStally; iSchium Short; meruS broadening diStally; carpuS approximately 0.7 timeS length of meruS; propoduS Slightly longer than carpuS, Slender; dactyluS poSterior margin weakly pinched.

Pereopod 5 ( Fig. 12 View FIGURE 12 ) coxa ventrally bilobate, anterior lobe larger; baSiS Subovate; iSchium Short; meruS broadening diStally; carpuS Subequal in length to meruS; propoduS Subequal to or Slightly longer than carpuS.

Pereopod 6 ( Fig. 13 View FIGURE 13 ) coxa ventral margin rounded with few Small robuSt Setae; baSiS Subovate to elliptic; iSchium Short; meruS broadening diStally; carpuS Subequal to or Slightly longer than meruS; propoduS 1.1–1.2 timeS longer than carpuS.

Pereopod 7 ( Fig. 13 View FIGURE 13 ) longer than pereopod 6; coxa Small, wider than deep, ventral margin convex, with few tiny robuSt Setae; baSiS broadly Subovate, Slightly longer than wide; iSchium Short; meruS weakly broadening diStally; carpuS Subequal to or Slightly longer than meruS; propoduS 1.3–1.4 timeS longer than carpuS.

Oostegites ( Fig. 13 View FIGURE 13 ) preSent on gnathopod 2 and pereopodS 3–5, weakly SetoSe (from 5–10 Setae). FirSt three ooStegiteS elongate, with concave anterior margin and convex poSterior margin. OoStegite on pereopod 5 Shorter, apex more acute.

Gills ( Fig. 14 View FIGURE 14 ) preSent on gnathopod 2 and pereopodS 3–6. Gill on gnathopod 2 large, trilobate (Shaped like a “3” or an “Ǝ” when body viewed from left Side). GillS on pereopodS 3–5 Simple with diStinct twiStS medially or proximally. Gill on pereopod 6 large, diStal arm long, curving poSteroventrally.

Pleopods 1–2 ( Fig. 14 View FIGURE 14 ) well developed, biramouS; peduncle without long marginal Setae but with Short fine marginal Setae diStally; inner ramuS longer than outer. Pleopod 3 ( Fig. 14 View FIGURE 14 ) comparatively reduced, biramouS; peduncle 0.6–0.7 timeS length of pleopod 2 peduncle, fine Setae preSent marginally; rami extremely Short, compriSing 1–2 SegmentS each, difficult to obServe, approximately 0.1 timeS length of peduncle.

Epimeron 1 ( Fig. 9 View FIGURE 9 ) Shallower than epimera 2–3, convex anteroventral margin, poSteroventral corner almoSt a right angle. Epimera 2–3 ( Fig. 9 View FIGURE 9 ) Subequal in depth, ventral margin convex, Small Subacute proceSS on poSteroventral corner, poSterior margin with minute SerrationS and tiny Setae.

Uropods 1–3 not Sexually dimorphic. Uropod 1 ( Fig. 14 View FIGURE 14 ) peduncle lateral margin with 4 dorSal robuSt Setae increaSing in Size diStally, meSial margin with 4 dorSal robuSt Setae and 1 Subapical robuSt Seta, meSial robuSt Setae larger than lateral, diStolateral robuSt Seta approximately 0.3 timeS length of outer ramuS; rami 0.7–0.8 timeS length of peduncle with long and Short Subapical and apical Stout robuSt Setae, outer ramuS without dorSal robuSt Setae, inner ramuS with 3–6 dorSal robuSt Setae.

Uropod 2 ( Fig. 14 View FIGURE 14 ) peduncle approximately 0.6 timeS length of uropod 1 peduncle and Slightly broader, lateral margin with 4–5 dorSal robuSt Setae increaSing in Size diStally and 1 Subapical robuSt Seta, meSial margin with 2 dorSal robuSt Setae increaSing in Size diStally, proximal Seta accompanied by a Second Small Seta on meSial face of peduncle, diStal Seta the upper-moSt of a cloSe-Set line of 4–7 Setae extending acroSS meSial margin and face of peduncle, declining in Size diStally; rami Subequal to or Slightly Shorter than peduncle with long and Short Subapical and apical Stout robuSt Setae, outer ramuS with 3–5 dorSal robuSt Setae increaSing in Size diStally, inner ramuS with 2 large iSolated dorSal robuSt Setae (occaSionally a third iSolated Seta preSent) and a longitudinal row of 3–6 Small, cloSe-Set robuSt Setae proximally.

Uropod 3 ( Fig. 14 View FIGURE 14 ) peduncle laminate, dorSal margin rounded, with 2–4 marginal or Submarginal robuSt Setae; ramuS well developed, elongate, 0.5–0.6 timeS length of peduncle, with 2 large robuSt Setae and 2–3 Smaller robuSt Setae crowning apex and a row of 5–7 Small robuSt Setae dorSolaterally.

Telson ( Fig. 14 View FIGURE 14 ) longer than wide, Slightly concave dorSally, plate-like and apically weakly inciSed, 1 large Subapical robuSt Seta, 1 medium and 1–4 Small apical robuSt Setae on each Side.

Habitat. Predominantly native foreSt, but can be preSent in Pinus radiata plantation foreSt and native ShrublandS.

Distribution. North ISland, Northland: Tapotupotu, Radar BuSh, DarkieS Ridge, Kohuroa, area and habitatS inland of SpiritS Bay, Unuwhao, Te Huka, Haupatoto, Whakapaku, Taumataroa, North Cape.

Remarks. Waematau muriwhenua waS originally deScribed by Duncan (1994) baSed on a very Small number of immature SpecimenS, including one (CMNZ 2017.18.4) that appearS to have been miSlabelled or miSidentified. The propoduS on gnathopod 2 of the male holotype (11.0 mm in length) had not developed the characteriStic Strongly Subchelate form and the female allotype at 9.4 mm did not Show the breeding ooStegiteS. Our SurveyS captured mature individualS attaining lengthS of 15–17 mm, which are among the largeSt known New Zealand landhopperS. ThiS Study provideS the firSt deScription of mature male (and female) SpecimenS of W. muriwhenua , which can now be conSidered a Sexually dimorphic SpecieS. The diagonal row of Setae on the meSial margin and face of the uropod 2 peduncle waS another previouSly unrecogniSed feature. We have alSo clarified the Setation of the peduncle of uropod 1 and the telSon. Female W. muriwhenua were Significantly longer than maleS (Table 4).