Canterburaturus cooki 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 : 24-26

Canterburaturus cooki Pesic & Smit sp. nov.

( Fig. 2F , 18A–I )

Type material. Holotype: male dissected and slide mounted in Hoyer's fluid. New Zealand, South Island, Selwyn River near Chamberlain's Ford, 21.x.2004. Paratypes: 0/1/0 (mounted), same data as holotype; 1/0/0, Selwyn River near Coalgate, 21.x.2004.

Diagnosis. Surface of dorsal sclerites rugose; projections associated with insertions of IV-L large; male gonopore triangle-shaped, located well anterior to the posterior end; P-2 without ventral projection and with several very small pointed projections distoventrally.

Description. Male. Integumental pigment absent; eye pigment slightly reduced; surface of sclerites rugose (as shown in Fig. 2F ); dorsal shield ( Fig. 18A ) L 229, W 203; anteromedial plate L 94, W 152; anterolateral platelets bearing a pair of glandularia; posterolateral platelets with one pair of glandularia; posteromedial plate bearing two pairs of glandularia; anterodorsal portion of ventral shield with a hood-like projection which does not extend to the tips of the first coxae ( Fig. 18C ); excretory pore located dorsally on a moderately developed terminal tubercle ( Fig. 18D ); ventral shield ( Fig. 18B ) L 352, W 266; capitular bay L 69; projections associated with insertions of IV-L large and extending to sides of idiosoma; a well developed ridge on each side extending posterolaterally from region of insertion of IV-L; a pair of short apodemes and a pair of glandularia located medial to insertions of IV-L; gonopore located well anterior to the posterior margin, L 37, W 27; five pairs of small setae immediately flanking the gonopore; acetabula difficult to see in the rugose integument; palp ( Fig. 18 F-G): total L 123, dL and %L (in parentheses): P-1, 15 (12.2); P-2, 32 (26.0); P-3, 20 (16.3); P-4, 40 (32.5); P-5, 16 (13.0); P-2 without ventral projection and with several very small denticles distoventrally; P-3 with a pointed projection ventrodistally; P-4 relatively long and without ventral projections; capitulum ( Fig. 18F ) ventral L 57; dL of IV-L-2-6: 57, 24, 29, 36, 46; maximum H of IV- L-2 30, IV-L-2 L/H ratio 1.9; chaetotaxy of IV-L as illustrated in Fig. 17 H; swimming hairs absent.

Female. Similar to male except for genital field ( Fig. 18I ); dorsal shield L 255, W 203; anteromedial plate L 92, W 145; ventral shield L 351, W 255; capitular bay L 69; gonopore terminal, L 40; palp ( Fig. 18E ): total L 119, dL and %L (in parentheses): P-1, 14 (11.8); P-2, 32 (26.9); P-3, 20 (16.8); P-4, 39 (32.8); P-5 14 (11.8); dL of IV-L-2-5: 53, 23, 28, 34; maximum H of IV-L-2, 28; IV-L-2 L/H ratio, 1.9.

Etymology. Named after Dr David Cook in appreciation of his studies of New Zealand water mites.

Remarks. Canterburaturus cooki resembles C. minutus in relatively small dimensions of idiosoma and gnathosoma and the P-2 lacking a ventrodistal projection, but differs in a different ornamentation of the dorsal shield (compare Figs. 2F and 2D ), the larger projections associated with insertions of the IV-L, the male gonopore triangle-shaped and located well anterior to the posterior margin, and presence of very small denticles on the ventral margin of P-2.

Ecology. The studied material was collected from the perennial 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 18 A – I. Canterburaturus cooki Pesic & Smit sp. nov., (A – B, D, F – H male, C, E, I female): A = dorsal shield; B, I = ventral shield; C = anterodorsal portion of ventral shield; D = posterior part of idiosoma, dorsal view; E, G = palp (P- 1 missing); F = capitulum, chelicera and palp; H = IV-L. Scale bars = 100 μm.

FIGURE 17 A – F. Canterburaturus novaeseelandicus Pesic & Smit sp. nov., female (A – D, F holotype, E paratype): A = dorsal shield; B = ventral shield; C = anterodorsal portion of ventral shield; D = palp; E = capitulum, chelicera and palp; F = IV-L. Scale bars = 100 μm.