Nesamblyops viator, 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 : 184-186

Nesamblyops viator , sp. nov.

Figures. 11B , 13E , 16D–F , 17K , 23

Type material. HOLOTYPE, male, in NZAC, labeled: \ NEW ZEALAND FD Resolution I Disappointment Cove 26 May 1982 \ C.F.Butcher ex moss \ NZ PB \. PARATYPES (49 specimens, dissected 7 exx.), 3 males and 1 female labeled same as paratype; 1 female labeled: \ NEW ZEALAND FD Bauza I 27 Nov 1981 C.F.Butcher \ litter and moss 81/187 \ NZ PB \; 1 male and 1 female labeled: \ NEW ZEALAND FD Bauza I 19 Mar 1984 C.F.Butcher Litter 84/55 \ NZ PB \; 3 males and 1 female labeled: \ Deep Cove Doubtful Snd \ Manapouri Exp. Jan 70 I.Townsend \ litter 70/65 \ DSIR \ Ns \ NZ PB \; 25 males and females labeled: \ Wilmot Pass 300m – 630m \ litter 70/73 \ Manapouri Exp. Jan 70 I.Townsend \ DSIR \ Ns \ NZ PB \; 4 females labeled: \ Wilmot Pass 630m – 800m \ litter 70/73 \ Manapouri Exp. Jan 70 J.Dugdale \ Mats 70/92 \ DSIR \ Ns \ NZ PB \; 1 female labeled: \ Spey R. 180m W.Manapauri Jan 70 A.C. Eyles Mats 70/62 \ NZ PB \; 1 female labeled: \ Spey River 180m \ Manapouri Exp. Jan 70 A.C. Eyles \ Mats 70/62 \ NZ PB \; 2 males labeled: \ Wilmot Pass 630m . W. of L.Manapouri \ 10 Jan 70 AC. Eyles Moss 70/34 \ NZ PB \; 1 male and 1 female labeled: \ NEW ZEALAND FD Secretary I Mt Grono, 853m 27 Nov 1981 C.F. Butcher \ mats, moss and tussock 81/186 \ NZ PB \; 2 females labeled: \ NEW ZEALAND FD Secretary I Grono Bay 28 Nov 1981 C.F.Butcher \ sifted litter 81/188 \ NZ PB \; 1 male labeled: \ NEW ZEALAND FD Secretary I Grono Bay Track 1 Dec 1981 C.F.Butcher \ Moss and litter 81/190 \ NZ PB \.

Etymology. The specific epithet is a Latin noun viator (meaning “traveler”) in apposition in the nominative case and refers to the peculiarities of the species distribution, which range encompasses the islands and mainland of the Fiordland region of New Zealand —carved by glaciers rugged terrain with largely inaccessible interior areas covered by dense primary vegetation.

Type locality. New Zealand, South Island , Fiordland, Resolution Island .

Recognition. Adults of this species ( Fig. 11B ) are practically indistinguishable from the adults of many Nesamblyops species based on external characters (e.g., Figs 10A–B ) and are distinguished from them by the structure of the male genitalia.

Description. Small for genus (SBL range 1.52–1.78 mm, mean 1.69± 0.065 mm, n=24).

Habitus. Body form ( Fig. 11B ) moderately convex, elongate ovoid, general proportions wide (WE/SBL 0.39±0.008), head moderately wide relative to pronotum (WH/WPm 0.75±0.015), proportions of pronotum in comparison to elytra average for genus (WPm/WE 0.73±0.020).

Color. Body color rufotestaceous, appendages testaceous.

Prothorax. Pronotum ( Fig. 13E ) moderately long in comparison to elytra (LP/LE 0.40±0.012) and slightly transverse (WPm/LP 1.20±0.023), with lateral margins strongly and rectilinear constricted posteriorly (WPm/ WPp 1.34±0.031). Anterior angles indistinct, posterior angles obtuse (120–130°), widely rounded. Width between posterior angles equals width between anterior angles (WPa/WPp 1.00±0.031). Basal margin slightly convex.

Elytra. Ovoid, narrowly depressed along suture, comparatively long (LE/SBL 0.60±0.007) and moderately wide (WE/LE 0.66±0.014). 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. 16F ) slightly arcuate and barely twisted. Shaft slightly enlarged at basal third, slightly tapering toward apex in apical two thirds. Apex slightly curved downward with rounded tip of moderate size. Apical orifice short, occupies one fifth of the shaft length. Ventral margin of median lobe slightly convex at middle part and slightly concave before the apex. Walls of shaft with two groups of poriferous canals in apical and basal parts of shaft. Dorsal copulatory sclerites represented by one dorsal membraneous field of distinctive shape ( Fig. 16F ). V-contour and rC-sclerite lacking. Left paramere ( Fig. 16D ) comparatively narrow, with slightly attenuated apex, bearing only two long setae. Right paramere ( Fig. 16E ) narrow, of moderate length, bearing two long setae, which are slightly shorter than the length of paramere. Ring sclerite as in Fig. 17K .

Female internal genitalia. Not examined.

Geographical distribution. The range of the species occupies the southwest corner of the South Island and comprises the central part of the Fiordland National Park ( Fig. 23 , black circles).

Habitat. Specimens were collected from litter, moss, tussock, and [plant] mats samples.

Relationships. The structure of the male genitalia of N. viator suggests its relatedness to the species with reduced and simple armature of the internal sac. In having only one sclerotized field of copulatory sclerites N. viator demonstrates affinity to and presumably forms one group with N. subcaecus .

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 11. Digital images of habitus of New Zealand Nesamblyops species, dorsal aspect. A—N. subrufus (Dublin Terrace, Upper Buller Gorge, Nelson, SO), B—N. viator (Secretary Island, Grono Bay, Fiordland, SO), C—N. victoriae (Capleston, Victoria Range, 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 16. Line drawings of male genitalia of New Zealand Nesamblyops species. N. subrufus (Dublin Terrace, Upper Buller Gorge, Nelson, SO): A—left paramere, left lateral aspect, B—right paramere, right lateral aspect, C—median lobe, right lateral aspect. N. viator (Secretary Island, Grono Bay, Fjordland, SO): D—left paramere, left lateral aspect, E—right paramere, right lateral aspect, F—median lobe, right lateral aspect. N. victoriae (Capleston, Victoria Range, Buller, SO): G—left paramere, left lateral aspect, H—right paramere, right lateral aspect, I—median lobe, right lateral aspect. Scale bar = 0.1 mm.

FIGURE 17. Line drawings of ring sclerite of New Zealand Nesamblyops species, male genitalia, dorsal aspect. A—N. canaanensis (Canaan, Nelson, SO), B—N. disjunctus (Fletchers Creek, Buller, SO), C—N. hobbit (Mount Domett, Nelson, SO), D—N. karamea (Karamea River Gorge, Nelson, SO), E—N. kuscheli (Flora Hut, Mount Arthur, Nelson, SO), F—N. montanus (Relax Shelter, Mount Robert Ridge, Nelson, SO), G—N. moorei (Kangaroo Creek, Mawhera Forest, Buller, SO), H—N. ovipennis (Mount Arthur, Nelson, SO), I—N. rotundicollis (Onekaka, Nelson, SO), J—N. subcaecus (Margarets Tarn Lake, Arthur’s Pass, Mid Canterbury, SO), K—N. viator (Secretary Island, Grono Bay, Fjordland, SO), L—N. victoriae (Capleston, Victoria Range, Buller, SO). Scale = 0.2 mm.

FIGURE 23. Distributional records for the Nesamblyops species and images of male median lobe, obtained from specimens, collected in the line-connected with images localities. Black circles—N. viator; red circles—N. magnificus. Scale bar = 0.5 mm.