Nesamblyops townsendi, Sokolov, 2023

Sokolov, Igor M., 2023, Eight new species of the genus Nesamblyops Jeannel (Anillini: Carabidae: Coleoptera) from New Zealand with notes about dispersal of the genus to the North Island, Zootaxa 5230 (2), pp. 179-201 : 196-198

Nesamblyops townsendi , sp. nov.

Figs. 3C , 4I , 6G–I , 7H , 9

Type material. HOLOTYPE, male, in NZAC, labeled: Tennyson Inlet Marlb. 22.5.64 J.I.Townsend \ Forest litter \ DSIR \ No \ NZ PB \. PARATYPES (12 specimens, in NZAC, dissected 4 exx.) , 1 female labeled same as holotype; 1 male labeled: \ Opouri Sdle. Tennyson Inlet Rd. 4.viii.67 \ F.Alack Litter 67/225 \ DSIR \ No \; 1 female labeled: \ Tennyson Inlet 22.5.64 litter J.I.Townsend \ NZ PB \; 2 males and 2 females labeled: \ M Robinson Ridge Kenepuru Sd. 500m Marlborough \ 13 Mar 1970 J.I. Townsend \ litter 70/142 \ DSIR \ No \ NZ PB \; 3 males labeled: \ Ship Cove 365m. SD 30 Nov. 72 J.S. Dugdale \ Litter 72/273 \ DSIR \ No \ NZ PB \; 1 female labeled: \ Shakespeare Bay , Picton \ 11 Aug 69 J.McBurney \ DSIR \ No \; 1 female labeled: \ Marlborough Mt.Robertson 1,600 16-5-60 I. Mannering \ Leafmould \ NZ PB \.

Etymology. The specific epithet is a Latinized eponym in the genitive case, and is based on the surname of James Ian Townsend, a famous New Zealand carabidologist and the collector of the type series.

Type locality. New Zealand, South Island, Marlborough Sounds, Tennyson Inlet .

Recognition. Adults of this species ( Fig. 3C ) can be distinguished from the adults of majority species of Nesamblyops by the distinctive shape of pronotum ( Fig. 4I ), however are practically indistinguishable from the adults of some Nesamblyops species (cf. with Figs. 2D ) and are distinguished from all of them by the structure of the male genitalia.

Description. Large for genus (SBL range 1.85–2.05 mm, mean 1.95± 0.071 mm, n=6).

Habitus. Body form ( Fig.3C )markedly convex, elongate ovoid, general proportions wide (WE/SBL 0.41±0.010), head narrow relative to pronotum (WH/WPm 0.66±0.014), proportions of pronotum in comparison to elytra average for genus (WPm/WE 0.77±0.013).

Color. Body color brunneopiceous, appendages brunneorufuos.

Prothorax. Pronotum ( Fig. 4I ) moderately long in comparison to elytra (LP/LE 0.44±0.009) and moderately transverse (WPm/LP 1.22±0.016), with lateral margins rectilinear and slightly constricted posteriorly (WPm/WPp 1.18±0.019). Anterior angles indistinct, posterior angles obtuse (94–100°), dented, and slightly protruding backward. Width between posterior angles much greater than between anterior angles (WPa/WPp 0.77±0.009). Basal margin concave.

Elytra. Ovoid, narrowly depressed along suture, comparatively long (LE/SBL 0.59±0.010) and moderately wide (WE/LE 0.69±0.008). Humeri completely rounded. Lateral margins slightly divergent at basal half, shortly subparallel at middle and evenly rounded to apex in apical half.

Male genitalia. Median lobe of aedeagus ( Fig. 6I ) strongly arcuate and moderately twisted. Shaft diverging basally, tapering in apical half. Apex moderately curved dorsally with narrowly rounded tip. Apical orifice long, occupies almost half of the shaft length. Ventral margin of median lobe straight. Walls of shaft with scattered poriferous canals. Dorsal copulatory sclerites in form of specific “bird’s head” plate, surrounded by small scaled membraneous field. Spines of internal sac absent. Left paramere ( Fig. 6G ) of normal proportions, with moderately attenuate apex, bearing three long setae. Right paramere ( Fig. 6H ) long and narrow, bearing three long setae, slightly shorter the length of paramere. Ring sclerite as on Fig. 7H .

Female internal genitalia. Not examined.

Geographical distribution. This species is distributed within the Marlborough Sounds area ( Crosby et al. 1998) ( Fig. 9 , yellow circles).

Habitat. According to label data specimens were collected from leafmold and litter without more precise data about plant communities.

Relationships. The structure of the male genitalia of N. townsendi suggests relationship to other species having dorsal copulatory sclerite in a shape of “bird’s head,” such as N. brouni , N. distinctus , and N. tararua . The state of the scaled membraneous field and the presence of the area with poriferous canals suggest that N. townsendi may share the common ancestry with N. tararua . Within-group relationships of N. townsendi remains to be examined.

Figures

FIGURE 2. Digital images of habitus of New Zealand Nesamblyops species, dorsal aspect. A—N. brouni (Lewis Pass, North Canterbury, SO), B—N. carltoni (Dun Mountain, Nelson, SO), C—N. confusus (Mount Stokes, Marlborough Sounds, SO), D—N. distinctus (Fabians Valley, Marlborough, SO), E—N. lescheni (D’Urville Island, Cook Strait, Marlborough Sounds, SO), F—N. oreobius (Mount Pirongia, Waikato, NO). Scale bar 1.0mm.

FIGURE 3. Digital images of habitus of New Zealand Nesamblyops species, dorsal aspect. A—N. parvulus (Mount Stokes, Marlborough Sounds, SO), B—N. tararua (Judd Ridge, Tararua Range, Wellington, NO), C—N. townsendi (Tennyson Inlet, Marlborough Sounds, SO). Scale bar 1.0mm.

FIGURE 4. Digital images of pronota of New Zealand Nesamblyops species, dorsal aspect. A—N. brouni (Lewis Pass, North Canterbury, SO), B—N. carltoni (Dun Mountain, Nelson, SO), C—N. confusus (Mount Stokes, Marlborough Sounds, SO), D—N. distinctus (Fabians Valley, Marlborough, SO), E—N. lescheni (D’Urville Island, Cook Strait, Marlborough Sounds, SO), F—N. oreobius (Mount Pirongia, Waikato, NO), G—N. parvulus (Mount Stokes, Marlborough Sounds, SO), H—N. tararua (Judd Ridge, Tararua Range, Wellington, NO), I—N. townsendi (Tennyson Inlet, Marlborough Sounds, SO). Scale bar 0.2mm.

FIGURE 6. Line drawings of male genitalia of New Zealand Nesamblyops species. N. parvulus (Mount Stokes, Marlborough Sounds, SO): A—left paramere, left lateral aspect, B—right paramere, right lateral aspect, C—median lobe, right lateral aspect. N. tararua (Judd Ridge, Tararua Range, Wellington, NO): D—left paramere, left lateral aspect, E—right paramere, right lateral aspect, F—median lobe, right lateral aspect. N. townsendi (Tennyson Inlet, Marlborough Sounds, SO): G—left paramere, left lateral aspect, H—right paramere, right lateral aspect, I—median lobe, right lateral aspect. Scale bar 0.1mm.

FIGURE 7. Line drawings of ring sclerite of New Zealand Nesamblyops species, male genitalia, dorsal aspect. A—N. brouni (Lewis Pass, North Canterbury, SO), B—N. carltoni (Dun Mountain, Nelson, SO), C—N. distinctus (Fabians Valley, Marlborough, SO), D—N. oreobius (Mount Pirongia, Waikato, NO), E—N. lescheni (D’Urville Island, Cook Strait, Marlborough Sounds, SO), F—N. parvulus (Mount Stokes, Marlborough Sounds, SO), G—N. tararua (Judd Ridge, Tararua Range, Wellington, NO), H—N. townsendi (Tennyson Inlet, Marlborough Sounds, SO). Scale = 0.4mm.

FIGURE 9. 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. tararua; yellow circles—N. townsendi; red circles—N. distinctus; green circles—N. brouni. Scale bar= 0.5mm.