Colobaturus selwynus Pesic & Smit sp. nov.

(Fig. 2A, 3A–B, 4A–C, 5A–B)

Type material. Holotype: male dissected and slide mounted in Hoyer's fluid. New Zealand, South Island: Selwyn River near Coalgate, riffle, 26.xi.2003. Paratypes: 0/1/0 (mounted), same location as holotype, 10.v.2004; 2/0/0, same location as holotype, 04.vi.2004; 1/0/0, same location as holotype, 08.iv.2004.

Diagnosis. Gnathosoma with very long basal apodeme.

Description. Male. Integumental pigment absent; eye pigment reduced; surface of sclerites smooth (as shown in Fig. 2A); dorsal shield (Fig. 3A) L 463, W 348; anteromedial plate L 181, W 241; anteromedial plate truncate anteriorly; posteromedial plate bearing three pairs of glandularia; four pairs of lateral platelets, none of which bear glandularia, the second pair being the largest; anterodorsal portion of ventral shield anteriorly rounded, extending anterior to tips of first coxae; ventral shield (Fig. 3B) L 534, W 434; capitular bay L 131; projections associated with insertions of IV–L small and continuing as a ridge on each side extending anterolaterally to margins of body; a pair of long shallow concavities beginning somewhat anterior to insertions of IV–L and extending along lateral margins of body nearly to the posterior end; posterior suture lines of fourth coxae prominent; fourth coxae with a pair of glandularia located more or less in a line with insertions of IV–L, but located more medially; suture lines of anterior coxae prominent and well separated from each other on their respective sides; gonopore nearly terminal, L 39, W 25; three pairs of very small setae closely flanking the gonopore; few acetabula present at extreme posterior end; palp (Fig. 4A): total L 223, dL and %L (in parentheses): P-1, 26 (11.7); P-2, 55 (24.7); P-3, 31 (13.9); P-4, 51 (22.9); P-5 60 (26.9); P-2 without ventral projection; P-4 with two somewhat thickened setae inserted close together and near middle of ventral margin; P-5 long and gradually tapering; capitulum (Fig. 4B) bearing very long basal apodeme, ventral L (without basal apodemes) 88, with basal apodeme 201; dL of IV-L-2-6: 55, 62, 79, 73, 71; chaetotaxy of fourth legs as illustrated in Fig. 4C; swimming hairs absent.

Female. Similar to male except for genital field (Fig. 5B); dorsal shield (Fig. 5A) L 522, W 350; anteromedial plate L 184, W 238; ventral shield L 553, W 484; capitular bay L 131; gonopore terminal and 118 in width at posterior end; palp: total L 224, dL and %L (in parentheses): P-1, 28 (12.5); P-2, 57 (25.5); P- 3, 30 (13.4); P-4, 49 (21.9); P-5 60 (26.8); capitulum ventral L (without apodemes) 85, with apodemes 214; dL of IV-L: 51, 62, 80, 73, 72.

Etymology. The species is named after the Selwyn River, where this species was collected. Remarks. This is the second known species of the genus Colobaturus Cook, 1991. The other, Colobaturus diamphidus Cook, 1991, was described from driven wells in the vicinity of Nelson, South Island (Cook 1991). The new species can be distinguished by the gnathosoma bearing very long basal apodemes (without basal apodeme in C. diamphidus —see Cook 1991).

Ecology. The studied material was collected from April to December, from the perennial-losing reach of the river.