Tyrphonothrus kimberleyi, Colloff, Matthew J., 2013

Colloff, Matthew J., 2013, Species-groups and biogeography of the oribatid mite family Malaconothridae (Oribatida: Malaconothroidea), with new species from the south-western Pacific region, Zootaxa 3722 (4), pp. 401-438 : 406-408

Tyrphonothrus kimberleyi sp. nov.

( Fig. 3 , 4 )

Dimensions. Holotype female length 495 Μm, breadth 290 Μm; paratypes (n = 10) mean length 502 Μm (range 470–542 Μm); mean breadth 282 Μm (range 272–293 Μm). Ratio of prodorsum to total length: 0.3 (holotype).

Female. Prodorsum. Rostrum rounded, smooth, porose ( Fig. 3 a). Rostral seta (ro) smooth, curved, flagelliform apically, 42 Μm long, shorter than mutual distance, emerging from alveolus on slight transverse indentation.

Lamellar seta (le) smooth, curved, flagelliform apically, 60 Μm long, as long as their mutual distance, enclosed by incurved, S-shaped lateral prodorsal ridge. Interlamellar seta (in) smooth, thin, extremely long (128 Μm), 7–8 × longer than seta ex. Prodorsum finely porose.

Notogaster. Anterior notogastral margin straight, transverse. Humeral region obtusely angled ( Fig. 3 a). With 15 pairs of smooth, thin, setiform setae. Setae e 2, h 2 and p 2 much longer (55–67 Μm long) than others (13–35 Μm long). Setae p 3 markedly anterior of p 2; p 3 30 Μm long, shorter than distance to p 2; p 2 on squat tubercle, 55 Μm long. Median longitudinal ridges absent but with vestiges of posterior M-shaped ridge in the form of semicircular indentations anterior of p 1 and posterolateral to h 2. Margins narrowing anteriorly, broadest in caudal region. Ratio of length to breadth 1.3. Caudal margin broadly rounded, indented at level of seta h 2. Notogaster densely porose interspersed with foveae.

Coxisternum. Epimeral setal formula 2-1-3-3. Epimeral setae smooth, setiform, minute ( Fig. 3 b). Setae on epimeral plates I and II 8–12 Μm long; setae 3b, 3c and 4a – c longer than others (15–20 Μm); 3b in lateral position; 4b in lateral position. Epimeral plates I separated medially, rounded anterolaterally. Epimeral plates II acute posterolaterally, partly fused medially. Epimeral plates III and IV separated medially. Apodeme IV, as far as posterolateral acetabulum, straight, transverse. Epimeral plate IV with blunt lateral spine.

Anogenital Region. With seven pairs of smooth genital setae, g 1-3 subequal in length (12–17 Μm), closely spaced, g 4-7 longer (23–31 Μm), spaced more broadly apart ( Fig. 3 b). Genital plates sub-rectangular; each plate 117 Μm long, 55 Μm broad, with well-developed median carina. Posterior margin of genital plate transverse, overlapping adanal plate. Anterior margin of adanal plate transverse, with sclerotised transverse region. Each adanal plate 127 Μm long, 47 Μm broad; three pairs of smooth, setiform setae, 17–27 Μm long. Two pairs of minute anal setae 5 Μm long.

Legs. Pre-tarsi homotridactylous; claws smooth ( Fig. 4 ). Tarsi long, thin: ratio of lengths to breadths: I 4.1; II 4.1; III 4.3; IV 5.3. Setal formula: Leg I 1-5 -4(1)-3(1)-11(3); Leg II 1-5 -4(1)-4(1)-10(1); Leg III 2-2 -1-2(1)-10; Leg IV 1-2 -1-2-10. Setae of Femur I barbed, setae of other segments on Leg I smooth except tc, u and pv. Proral setae (p) short, broad basally; those on Tarsi I flagelliform apically, others spiniform. Primiventral setae (pv) on Tarsus I heavily barbed, expanded ( Fig. 4 b). Solenidia ω1-3 clustered. Famulus (ε) spiniform, peg-like, 10 Μm long. Fastigial setae on Tarsus I heteromorphic: both long, curved but ft ’ thicker and longer than ft ”. Setae ft ” and ft ’ on tarsi II similarly shaped, both sparingly barbed, ft ’ thicker and longer ( Fig. 4 c); those on tarsi III heteromorphic; ft ” long, thin, straight, ft ’ thicker and curved; both smooth ( Fig. 4 d). Tarsus IV with seta ft ” curved, pointed, smooth; seta s smooth, primiventral setae sparingly barbed ( Fig. 4 e).

Material examined. Adult female holotype and 15 paratypes, moss, Corin Forest, Namadji National Park, Australian Capital Territory, 35°30'50"S, 148°55'08"E, 1250 m., coll. M.J. Colloff, 21.vi.1995. Holotype and paratypes deposited in the Australian National Insect Collection, CSIRO Ecosystem Sciences, Canberra.

Etymology. This species is named after my eldest step-son, Kimberley Garth Dent.

Remarks. Tyrphonothrus kimberleyi sp. nov. differs from other members of the genus by the following combination of characters: 1) the long, thin interlamellar setae; 2) the straight, transverse anterior notogastral margin; 3) the foveolate notogaster; 4) the vestigial, posterior notogastral ridge in the form of semicircular indentations; 5) the extremely short setae p 1; 6) the epimeral setal formula 2-1-3-3; 7) the seven pairs of genital setae; 8) the two pairs of anal setae; 9) the sclerotised transverse region on the anterior margin of the adanal plate.

Tyrphonothrus kimberleyi sp. nov. shares with T. aquatilis (Fain, Lambrechts & Wauthy 1990) , T. foveolatus (Willmann, 1931) , T. glaber (Michael, 1888) and T. maior (Berlese, 1910) seven pairs of setae and reduced or vestigial elements of the longitudinal and posterior M-shaped ridges, foveolate notogastral cuticle and setae pv of Tarsus I heavily barbed and expanded (expect in T. foveolatus for which setae pv have not been described). Tyrphonothrus kimberleyi differs from T. aquatilis in that the latter species has the shorter notogastral setae barbed. Tyrphonothrus kimberleyi has much longer interlamellar and exobothridial setae than T. glaber and T. foveolatus and much longer adanal and anal setae and shorter lamellar setae than T. maior .

Figures

FIGURE 3. Tyrphonothrus kimberleyi sp. nov., holotype female; a) dorsal; b) ventral.

FIGURE 4. Tyrphonothrus kimberleyi sp. nov., left legs, left-hand view; a) Leg I; b) detail of primiventral setae on Tarsus I; c) Leg II; d) Leg III; e) Leg IV.