Zeanillus nanus, sp.n.

Figs. 1 F, 5F, 7I, 11J, 13I –L, 14F, 15J, 16H, 17C, 18B

Type material. HOLOTYPE, male, in NZAC, board-mounted, undissected, labeled: / New Zealand DN Start of Government Tck Waipori Valley / Washed soil sample 17 Dec 06 /.

PARATYPES (24 specimens, 7 dissected), 1 male and 1 female labeled same as holotype; 1 male labeled: / New Zealand CO Snow Farm Pisa Range 15.02.0 7 / Tussock litter /; 1 female labeled: / New Zealand CO Snow Farm, Pisa Range, 1520m, moss and soil sample, subalpine tussockland, F41/001852 J.Nunn 17 Jan 2008 /; 1 male and 2 females labeled: / New Zealand DN Goodwood SR Palmerston 9 Jul 0 6 / Soil sample, dry kowhai/totara forest /; 1 male labeled: / New Zealand: DN, Goodwood Scenic Reserve, nr Palmerston J. Nunn 5 Oct 2008 /; 1 male labeled: / New Zealand SL Manuka Ridge Blue Mountains 19 Aug 0 6 / Washed soil sample, 600m G44: 333754 /; 2 males and 5 females labeled: / New Zealand SL Otanomomo SR Balclutha 1 Jan 0 7 / Washed soil sample, coastal podocarp forest /; 5 males and 3 females labeled: / New Zealand SL Toms Creek Beaumont Forest 19 Aug 0 6 / Washed soil sample, 40m G45: 365676 /.

Specific epithet. The specific epithet is a Latinized adjective in the masculine form and is derived from the Greek word νᾶνος (nānos), meaning “dwarf”. The epithet refers to the small size of members of this species.

Type locality. New Zealand, South Island, Otago, Waipori River Valley, Government Track area.

Recognition. Adults of this species (Fig. 11 J) are distinguished from other congeners by the characters listed in the subgeneric diagnosis.

Description. Size. Small to medium for genus (SBL range 1.46–1.78 mm, mean 1.64± 0.071 mm, n=20).

Habitus. Body form subdepressed, subparallel, moderately elongate (WE/SBL 0.36±0.016), head of moderate width for genus compared to pronotum (WH/WPm 0.74±0.019), pronotum of moderate width in comparison to elytra (WPm/WE 0.71±0.016).

Color. Body color testaceous, appendages testaceous.

Prothorax. Pronotum slightly long (LP/LE 0.39±0.016) and moderately elongate (WPm/LP 1.27±0.042), with rectilinear and markedly constricted posteriorly lateral margins (WPm/WPp 1.79±0.114). Width between anterior angles much greater than between posterior angles (WPa/WPp 1.42±0.099), which are almost completely effaced.

Elytra. Moderately depressed, comparatively long (LE/SBL 0.51±0.016) and moderately wide (WE/LE 0.71±0.032). Lateral margins slightly divergent at basal forth, subparallel at middle and evenly rounded to apex in apical third.

Male genitalia. Median lobe (Fig. 13 I) with slightly bisinuate ventral margin and semicircular short apex. Apical orifice area without ostial fields. Sclerites of internal sac sclerotized, with similar branches united basally, shorter than the half of the distance between apical and basal orifices. Left paramere with short apical constriction (Fig. 13 K). Ring sclerite with short transverse handle (Fig. 14 F).

Female internal genitalia. Goncoxite 2 with short ensiform setae (Fig. 15 J). Spermatheca sclerotized, elongate, linear, with three compartments (Fig. 16 H). Spermathecal duct short and without coils. Attachments of spermathecal duct and gland to spermatheca distant from each other.

Geographical distribution. This species inhabits the coastal plains of North and South Otago, from Palmerston southwards to the Catlins, also penetrating the interior highlands upstream along the Clutha River almost to Lake Wanaka (18B, green diamonds). In main features, the pattern of distribution of Z. nanus resembles that of Z. pallidus.

Way of life. Specimens were collected in a wide range of habitats: tussockland, coastal podocarp, and dry kowhai/totara forests.

Relationships. In the structure of male median lobe and spermatheca, members of this species are distinct from those of the other species of subgenus. In the shape of round sclerite, males of this species are similar to those of Z. carltoni. Relationships of Z. nanus are not postulated here.