Taintaturus selwynus Pesic & Smit

Pesic, Vladimir, Smit, Harry & Datry, Thibault, 2010, Water mites (Acari: Hydrachnidia) from the hyporheic waters of the Selwyn River (New Zealand), with descriptions of nine new species, Zootaxa 2355, pp. 1-34 : 8-10

Taintaturus selwynus Pesic & Smit sp. nov.

( Fig. 2B , 6A–F , 7A–C )

Type material. Holotype: male dissected and slide mounted in Hoyer's fluid. New Zealand, South Island: Selwyn River near Old Bridge, riffle, 04.vi.2004. Paratypes: 0/1/0, same location as holotype, 08.vii.2004; 0/ 1/0 (mounted), same location as holotype, 10.ix.2004; 1/0/0 (mounted), Selwyn River near Rayvell Farm, 08.vii.2007; 0/1/0 (damaged, dorsal shield and legs missing, mounted), Selwyn River near Rayvell Farm, 22.xi.2004; 1/0/0, Selwyn River near Chamberlain's Ford, 23.v.2005; 0/1/0 (damaged, palps and legs missing), Selwyn River near Ridgens, riffle, 20.viii.2004.

Diagnosis. Surface of dorsal sclerites smooth; ventral margin of P-2 with a rounded extension, with irregularly rugose surface, P-3 distoventrally with a pointed projection.

Description. Male (holotype, in parentheses some measurements of paratype). Integumental pigment absent; eye pigment reduced; surface of sclerites smooth (as shown in Fig. 2B ); dorsal shield ( Fig. 6A ) L 316 (319), W 275 (281); anteromedial plate L 144 (152), W 188 (195); anterolateral platelets bearing a pair of glandularia; a pair of small glandularia lying free in the integument between anterolateral and posterolateral platelets; posteromedial plate bearing two pairs of glandularia; anterodorsal portion of ventral shield forming a pointed hood-like projection extending beyond anterior margin of first and second coxae ( Fig. 6C ); ventral shield ( Fig. 6B ) L 405 (425), W 375 (343); tips of first, second and third coxae somewhat pointed and with well developed intercoxal slots; projections associated with insertions of IV-L broad and somewhat truncate; a well developed ridge on each side extending posterolaterally from region of insertion of IV-L; a pair of apophyses and a pair of glandularia located immediately medial to insertions of IV-L; gonopore terminal, L (31); genital acetabula numerous; ejaculatory complex L (71); palp ( Fig. 6 D-E): total L 159, dL: P-1, 24; P-2, 40 (41); P-3, 24 (25); P-4, 49 (52); P-5, 22 (22); %L: P-1, 15.1; P-2, 25.2; P-3, 15.1; P-4, 30.8; P-5, 13.8; ventral margin of P-2 with a rounded extension, with irregularly rugose surface; P-3 distoventrally with a pointed projection; capitulum ventral L (71); dL of IV-L: 49 (50), 78 (83), 38 (36), 59 (60), 62 (62), 66 (68); maximum H of IV-L-2, (49); IV-L-2 L/H ratio, (1.69); chaetotaxy of IV-L as illustrated in Fig. 6F ; swimming hairs absent.

Female. Similar to male except for genital field ( Fig. 7A ); dorsal shield L 327, W 298; anteromedial plate L 152, W 198; ventral shield L 430, W 344; capitular bay L 109; gonopore terminal, L 113, W 72; palp ( Fig. 7B ): total L 163, dL and %L (in parentheses): P-1, 23 (14.1); P-2, 42 (25.8); P-3, 23 (14.1); P-4, 53 (32.5); P- 5, 22 (13.5); dorsal L of IV-L-2-6: 84, 35, 57, 62, 68; maximum H of IV-L-2, 50; IV-L-2 L/H ratio, 1.68. Etymology. The species is named after the type locality, the Selwyn River.

Remarks. Due to the combination of relatively wide anteromedial (L/W ratio, 0.77–0.78) and posteromedial (L/W ratio, 0.98) plates of the dorsal shield, a smooth surface of dorsal sclerites, the coxae projecting far beyond the pointed dorsomedial projection of the ventral shield, and P-2 and -3 bearing ventral projections, the new species resembles Taintaturus livingstoni Cook, 1991 , known from driven wells in the vicinity of Nelson (South Island, New Zealand). Taintaturus selwynus can be easily distinguished from T. livingstoni in the rounded ventrodistal projection of P-2 with irregularly rugose surface vs. P-2 with a pointed projection near middle of ventral side in T. livingstoni (see: Cook 1991).

Ecology. The studied material was collected from June to December, from ephemeral-losing (Ridgens), intermittent-gaining (Rayvell Farm) and the perennial-gaining (Old Bridge and Chamberlain's Ford) reaches of the river.

Figures

FIGURE 2 A – L. Photographs of dorsal shield. A— Colobaturus selwynus Pesic & Smit n. sp., female; B— Taintaturus selwynus Pesic & Smit n. sp., male; C— T. rostratus Pesic & Smit n. sp., female; D— Canterburaturus minutus Pesic & Smit n. sp., male; E— C. novaeseelandicus Pesic & Smit n. sp., female; F— C. cooki Pesic & Smit n. sp., female; G— Abelaturus schwoerbeli Pesic & Smit n. sp., male; H— A. schwoerbeli Pesic & Smit n. sp., female; I— Abelaturus cornophorus Cook, 1983, female; J— Piotaturus bovalus Cook, 1983, male; K— Paratryssaturus cantermus Cook, 1983, female; L— Zelandalbia longipalpis Pesic & Smit n. sp., female.

FIGURE 6 A – F. Taintaturus selwynus Pesic & Smit sp. nov., male (A – D, F holotype, E paratype): A = dorsal shield; B = ventral shield; C = anterodorsal portion of ventral shield; D = palp; E = palp (P- 1 missing); F = IV-L. Scale bars = 100 μm.

FIGURE 7 A – C. Taintaturus selwynus Pesic & Smit sp. nov., female: A = ventral shield; B = palp, capitulum and chelicera; C = I-L- 5 - 6. Scale bars = 100 μm.