Nesamblyops magnificus, 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 : 171-172

Nesamblyops magnificus , sp. nov.

Figures. 9F , 12F , 14P–R , 18A , 23

Type material. HOLOTYPE, male, in NZAC, labeled: \ New Zealand DN Allison Res Akatore 21 May 06 / Washing soil from forest /. PARATYPES (11 specimens, dissected 5 exx.), 1 male and 4 females labeled same as holotype; 1 male labeled: \ New Zealand DN Allison Res S of Akatore 24 Feb 01 / In earthy forest floor litter / Zeanillus sp. det. JTN 2/01 /; 1 female labeled: \ New Zealand DN Allison Reserve nr Akatore 9 Aug 08 / Washed soils sample near stream \; 1 male labeled: \ New Zealand-DN: Allison Reserve, Akatore, broadleaf/podocarp forest, 150m, washed soil sample, M31:602701 J.Nunn 2 Dec 2007 / Molecular voucher № 85 Sokolov I.M. 2008 \; 1 female labeled: \ Waipori Falls 1000’ 15.I.65 Kuschel + Townsend \ DSIR \ Ns \ Digitally imaged May / June 2001 B.Rhode \ NZ PB \; 1 male and 1 female labeled: \ Waipori Pond Otago 8.IX.68 J.C. Watt \ Moss + Litter 68/111 \ DSIR \ Ns \ NZ PB \.

Etymology. The specific epithet is a Latin adjective, magnificus (meaning “splendid, rich”) in the masculine form, and refers to the wonderful structure of the male median lobe.

Type locality. New Zealand, South Island, Coastal Otago, Allison Conservation Area .

Recognition. Adults of this species ( Fig. 9F ) can be easily distinguished from the adults of all Nesamblyops species by the absence of “eyes”, which other species of the genus have in a diminutive state (one ommatidium with underlying pigmented spot), and by the structures of the male genitalia.

Description. Large for genus (SBL range 1.81–2.01 mm, mean 1.93± 0.078 mm, n=6).

Habitus. Body form ( Fig. 9F ) slightly convex, elongate ovoid, general proportions moderately narrow (WE/ SBL 0.37±0.009), head moderately wide relative to pronotum (WH/WPm 0.73±0.011), proportions of pronotum in comparison to elytra slightly wide for genus (WPm/WE 0.78±0.030).

Color. Body color rufotestaceous, appendages testaceous.

Prothorax. Pronotum ( Fig. 12F ) moderately long in comparison to elytra (LP/LE 0.42±0.014) and moderately transverse (WPm/LP 1.22±0.026), with lateral margins arcuately constricted posteriorly (WPm/WPp 1.31±0.055). Anterior angles indistinct, posterior angles strongly obtuse (124–133°), almost completely rounded. Width between posterior angles equals the width between anterior angles (WPa/WPp 0.96±0.052). Basal margin almost rectilinear, slightly convex at middle.

Elytra. Ovoid, widely depressed along suture, comparatively long (LE/SBL 0.57±0.007) and moderately narrow (WE/LE 0.65±0.019). 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. 14R ) strongly arcuate and slightly twisted. Shaft subparallel in basal half, slightly tapering in apical half towards apex. Apex straight, enlarged, with curved downward, triangular, narrowly rounded tip. Apical orifice long, occupies apical half of the shaft length. Ventral margin of median lobe slightly convex. Walls of shaft with small group of poriferous canals near basal orifice. Copulatory sclerites greatly enlarged, occupying almost half of the shaft length, though in general shape following typical design of Nesamblyops . Dorsal V-contour consists of moderately sclerotized fields protruding from basal orifice and prolonging apically in short spiral ribbon with acutely pointed tip. Medial rC-sclerite has elongated ventral branch with acute apical part, and distinctive exterior edge also protruding from basal orifice ( Fig. 14R ). Left paramere ( Fig. 14P ) comparatively narrow, with moderately attenuated apex, bearing two long setae. Right paramere ( Fig. 14Q ) short, of moderate width, bearing two long setae, which are shorter than the length of paramere. Ring sclerite not examined.

Female internal genitalia. Spermatheca ( Fig. 18A ) with two sclerotized compartments, larger ball-shaped distal part, and short, tube-like part representing a sclerotized continuation of the spermathecal duct. Tube-like part bears spermathecal gland, which is longer than the length of spermatheca. Spermathecal duct short, approximately equals the length of spermathecal gland.

Geographical distribution. The range of the species situated in the southeast corner of the South Island and restricted to the territories associated with the lower course of the Taieri River ( Fig. 23 , red circles).

Habitat. Specimens were mostly collected using washing technique from soil samples (labels mention broadleaf/ podocarp forest), few specimens were taken from moss and forest litter also.

Relationships. The structures of the male genitalia and the shape of spermatheca of N. magnificus suggest its relatedness to the other species of the genus having V-contour and rC-sclerites in the internal sac of the median lobe. However, hypertrophy of the copulative sclerites makes other assumptions on the relationships of N. magnificus impossible. Presumably this species is a remote relative of the other species of Nesamblyops with bisetose parameres.

Figures

FIGURE 9. Digital images of habitus of New Zealand Nesamblyops species, dorsal aspect.A—N. canaanensis (Canaan, Nelson, SO), B—N. disjunctus (Fletchers Creek, Buller, SO), C—N. hobbit (9mi. N Karamea, Nelson, SO), D—N. karamea (Karamea River Gorge, Nelson, SO), E—N. kuscheli (Flora Hut, MountArthur, Nelson, SO), F—N. magnificus (Allison Reserve,Akatore, Dunedin, SO). Scale bar = 1.0 mm.

FIGURE 12. Digital images of pronota of New Zealand Nesamblyops species, dorsal aspect. A—N. canaanensis (Canaan, Nelson, SO), B—N. disjunctus (Fletchers Creek, Buller, SO), C—N. hobbit (9mi. N Karamea, Nelson, SO), D—N. karamea (Karamea River Gorge, Nelson, SO), E—N. kuscheli (Flora Hut, Mount Arthur, Nelson, SO), F—N. magnificus (Allison Reserve, Akatore, Dunedin, SO), G—N. montanus (Lake Sylvester, Kahurangi National Park, Nelson, SO), H—N. moorei (Kangaroo Creek, Mawhera Forest, Buller, SO), I—N. ovipennis (Mount Arthur, Nelson, SO). Scale bar = 0.2 mm.

FIGURE 14. Line drawings of male genitalia of New Zealand Nesamblyops species. N. canaanensis (Canaan, Nelson, SO): A—left paramere, left lateral aspect, B—right paramere, right lateral aspect, C—median lobe, right lateral aspect. N. disjunctus (Fletchers Creek, Buller, SO): D—left paramere, left lateral aspect, E—right paramere, right lateral aspect, F—median lobe, right lateral aspect. N. hobbit (Mount Domett, Nelson, SO): G—left paramere, left lateral aspect, H—right paramere, right lateral aspect, I—median lobe, right lateral aspect. N. karamea (Karamea River Gorge, Nelson, SO): J—left paramere, left lateral aspect, K—right paramere, right lateral aspect, L—median lobe, right lateral aspect. N. kuscheli (Flora Hut, Mount Arthur, Nelson, SO): M—left paramere, left lateral aspect, N—right paramere, right lateral aspect, O—median lobe, right lateral aspect. N. magnificus (Allison Reserve, Akatore, Dunedin, SO): P—left paramere, left lateral aspect, Q—right paramere, right lateral aspect, R—median lobe, right lateral aspect. Legend: rCs—reversed C-contour; Vs—V-contour. Scale bar = 0.1 mm.

FIGURE 18. Line drawings of spermatheca of New Zealand Nesamblyops species. A—N. magnificus (Allison Reserve, Akatore, Dunedin, SO), B—N. rotundicollis (Parahamoi, Nelson, SO), C—N. subcaecus (Lake Kaniere Scenic Reserve, Mount Tuhua, Westland, SO). Scale = 0.1 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.