Nesamblyops solitarius, Sokolov, 2023

Sokolov, Igor M., 2023, Fourteen new species of the genus Nesamblyops Jeannel (Coleoptera: Carabidae: Anillini) from the South Island of New Zealand with redescription of the genus and description of a new subtribe, Zootaxa 5375 (2), pp. 151-192 : 179-180

Nesamblyops solitarius , sp. nov.

Figures. 10E , 13B , 15M–O , 20

Type material. HOLOTYPE, male, in NZAC, labeled, dissected: \ NEW ZEALAND BR Boatmans Ck 4.5km SE of Cronodun Nov 1971 J.McBurney Litter 71/140 \ Beech Forest Utilization Project \ DSIR \ No \ NZ PB \. PARATYPES (2 specimens, dissected 1 ex.), 1 male and 1 female labeled: \ NEW ZEALAND BR 1.6km NW of Capleston Italians Ck 21 Apr 1972 \ J.S. Dugdale moss and litter 71/98 \ Beech Forest Utilization Project \ DSIR \ No \ NZ PB \.

Etymology. The specific epithet is a Latin adjective, solitarius (meaning “living alone”), in the masculine form, and is alluding to the small number of specimens of this species, which are known to science at present.

Type locality. New Zealand, South Island, West Coast, western foothills of Victoria Range, Capleston area .

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

Description. Large for genus (SBL range 2.02–2.08 mm, mean 2.05± 0.042 mm, n=2).

Habitus. Body form ( Fig. 10E ) moderately convex, elongate ovoid, general proportions slightly wide (WE/SBL 0.38±0.003), head narrow relative to pronotum (WH/WPm 0.70±0.005), proportions of pronotum in comparison to elytra average for genus (WPm/WE 0.76±0.003).

Color. Body color rufotestaceous, appendages testaceous.

Prothorax. Pronotum ( Fig. 13B ) moderately long in comparison to elytra (LP/LE 0.42±0.006) and slightly transverse (WPm/LP 1.17±0.012), with lateral margins slightly and rectilinear constricted posteriorly (WPm/ WPp 1.20±0.029). Anterior angles indistinct, posterior angles obtuse (124–125°), widely rounded. Width between posterior angles greater than between anterior angles (WPa/WPp 0.83±0.014). Basal margin slightly convex.

Elytra. Ovoid, moderately depressed along suture, comparatively long (LE/SBL 0.59±0.012) and moderately narrow (WE/LE 0.64±0.018). Humeri completely rounded. Lateral margins slightly divergent at basal third, subparallel at middle and evenly rounded to apex in apical third.

Male genitalia. Median lobe of aedeagus ( Fig. 15O ) moderately arcuate and slightly twisted. Shaft almost subparallel in basal half, moderately tapering in apical half. Apex long and straight with slightly dilated symmetrical rounded tip. Apical orifice long, occupies almost one half of the shaft length. Ventral margin of median lobe almost straight. Walls of shaft with several poriferous canals scattered across shaft body. Dorsal copulatory sclerites atypical for genus. V-contour and rC-sclerite lacking. Only dorsal membraneous field with narrow sclerotization at its dorsal edge exists at the middle of shaft ( Fig. 15O ). In addition, internal sac has a scaly membraneous field at apical orifice. Left paramere ( Fig. 15M ) comparatively wide, with shortly attenuate apex, bearing two long setae. Right paramere ( Fig. 15N ) narrow, of moderate length, bearing two long setae, which are shorter than the length of paramere. Ring sclerite not investigated.

Female internal genitalia. Not examined.

Geographical distribution. The range of the species lies in the northern half of the West Coast region, where the species was collected in two localities around Capleston at the foothills of the Victoria Range ( Fig. 20 , green circles).

Habitat. Specimens were collected from moss and litter samples.

Relationships. The structure of the male genitalia and parameres of N. solitarius suggests its relatedness to N. rotundicollis and N. subrufus , described below. All three species share bisetose parameres and the lack of rC-sclerite in the internal sac of median. Also, all three species have presumably a synapomorphic character—a scaly membraneous field near apical orifice.

Figures

FIGURE 10. Digital images of habitus of New Zealand Nesamblyops species, dorsal aspect. A—N. montanus (Lake Sylvester, Kahurangi National Park, Nelson, SO), B—N. moorei (Kangaroo Creek, Mawhera Forest, Buller, SO), C—N. ovipennis (Mount Arthur, Nelson, SO), D—N. rotundicollis (Onekaka, Nelson, SO), E—N. solitarius (Italian Creek, Capleston, Buller, SO), F—N. subcaecus (Sharp) (Greymouth, Buller, SO). Scale bar = 1.0 mm.

FIGURE 13. Digital images of pronota of New Zealand Nesamblyops species, dorsal aspect. A—N. rotundicollis (Onekaka, Nelson, SO), B—N. solitarius (Italian Creek, Capleston, Buller, SO), C—N. subcaecus (Greymouth, Buller, SO), D—N. subrufus (Dublin Terrace, Upper Buller Gorge, Nelson, SO), E—N. viator (Secretary Island, Grono Bay, Fiordland, SO), F—N. victoriae (Capleston, Victoria Range, Buller, SO). Scale bar = 0.2 mm.

FIGURE 15. Line drawings of male genitalia of New Zealand Nesamblyops species. N. montanus (Relax Shelter, Mount Robert Ridge, Nelson, SO): A—left paramere, left lateral aspect, B—right paramere, right lateral aspect, C—median lobe, right lateral aspect. N. moorei (Kangaroo Creek, Mawhera Forest, Buller, SO): D—left paramere, left lateral aspect, E—right paramere, right lateral aspect, F—median lobe, right lateral aspect. N. ovipennis (Mount Arthur, Nelson, SO): G—left paramere, left lateral aspect, H—right paramere, right lateral aspect, I—median lobe, right lateral aspect. N. rotundicollis (Onekaka, Nelson, SO): J—left paramere, left lateral aspect, K—right paramere, right lateral aspect, L—median lobe, right lateral aspect. N. solitarius (Italian Creek, Capleston, Buller, SO): M—left paramere, left lateral aspect, N—right paramere, right lateral aspect, O—median lobe, right lateral aspect. N. subacecus (Margarets Tarn Lake, Arthur’s Pass, Mid Canterbury, SO): P—left paramere, left lateral aspect, Q—right paramere, right lateral aspect, R—median lobe, right lateral aspect. Scale bar = 0.1 mm.

FIGURE 20. Distributional records for the Nesamblyops species and images of male median lobe, obtained from specimens, collected in the line-connected with images localities. Green circles—N. solitarius; black circles—N. montanus; pink circles— N. rotundicollis; red circles—N. subrufus. Scale bar = 0.5 mm.