Nesamblyops karamea, sp. nov.

Figures. 9D, 12D, 14J–L, 17D, 19

Type material. HOLOTYPE, male, in NZAC, labeled: \ Karamea River Gorge. F.Alack 24.vi.67 \ litter 67/216 \ DSIR \ No \ NZ PB \. PARATYPES (9 specimens, dissected 2 exx.), 1 male and 2 females labeled same as holotype; 2 males labeled: \ Karamea Val. F.Alack 21.vi.67 \ litter 67/218 \ DSIR \ No \ NZ PB \; 1 male and 3 females labeled: \ 6m . up Little Wanganui R. West Nelson. \ F.Alack 24.vi.67 \ litter 67/211 \ DSIR \ No \ NZ PB \.

Etymology. The specific epithet is a noun in apposition in the nominative case and refers to the name of the river gorge from which the new species is described.

Type locality. New Zealand, South Island, West Coast, Kahurangi National Park, the Karamea River Gorge area .

Recognition. Adults of this species (Fig. 9D) are practically indistinguishable from the adults of many Nesamblyops species based on external characters (e.g., Figs 9C, 10C) and are distinguished from them by the structures of the male genitalia.

Description. Of moderate size for genus (SBL range 1.67–1.91 mm, mean 1.79± 0.076 mm, n=9).

Habitus. Body form (Fig. 9D) markedly convex, elongate ovoid, general proportions wide (WE/SBL0.40±0.010), head narrow relative to pronotum (WH/WPm 0.68±0.015), proportions of pronotum in comparison to elytra average for genus (WPm/WE 0.75±0.013).

Color. Body color brunneorufous, appendages testaceous.

Prothorax. Pronotum (Fig. 12D) moderately long in comparison to elytra (LP/LE 0.42±0.010) and moderately transverse (WPm/LP 1.22±0.024), with lateral margins arcuately constricted posteriorly (WPm/WPp 1.31±0.049). Anterior angles indistinct, posterior angles obtuse (107–119°), rounded. Width between posterior angles greater than between anterior angles (WPa/WPp 0.89±0.027). Basal margin almost rectilinear, slightly convex at middle.

Elytra. Ovoid, narrowly depressed along suture, comparatively long (LE/SBL 0.59±0.007) and moderately wide (WE/LE 0.68±0.020). Humeri completely rounded. Lateral margins slightly divergent at basal half, subparallel at middle and evenly rounded to apex in apical third.

Male genitalia. Median lobe of aedeagus (Fig. 14L) moderately arcuate and moderately twisted. Shaft short, convex dorsally, tapering in apical half. Apex moderately curved dorsally with rounded tip. Apical orifice long, occupies almost half of the shaft length. Ventral margin of median lobe straight. Walls of shaft without poriferous canals. Dorsal copulatory sclerites with well-developed rC-sclerite and with moderately long V-contour (Fig. 14L). Additionally, internal sac possesses curved narrowly sclerotized fold apico-ventrally from rC-sclerite. Left paramere (Fig. 14J) comparatively narrow, with slightly tapering apex, bearing three long setae. Right paramere (Fig. 14K) of moderate length, bearing three long setae, which are slightly shorter than the length of paramere. Ring sclerite as in Fig. 17D.

Female internal genitalia. Not examined.

Geographical distribution. The range of the species occupies the northern part of the West Coast presumably between the Karamea and the Wanganui Rivers (Fig. 19, yellow circles).

Habitat. Specimens were collected from litter samples.

Relationships. The structure of the male genitalia of N. karamea suggests its relatedness to the other species with well-developed rC-sclerite and V-contour in the internal sac of the median lobe (cf. with the sclerites of N. carltoni, Fig. 5F, p. 190, Sokolov 2023). However, some details in the internal sac such as a presence of additional curved sclerotized fold apico-ventrally point out on isolated position of N. karamea within the genus. Taking in account the trisetose parameres and a shape of median lobe this species may have a remote relatedness to the group of species, which includes N. canaanensis, N. hobbit, and N. ovipennis .