Nebria (Sadonebria) tenuicaulis, Sasakawa, Kôji & Kubota, Kôhei, 2006

Sasakawa, Kôji & Kubota, Kôhei, 2006, Nebria tenuicaulis sp. nov., a sympatric species with Nebria sadona ohdaiensis Nakane, with studies on the phylogeny of the subgenus Sadonebria Ledoux & Roux (Coleoptera: Carabidae), Zootaxa 1306, pp. 41-50 : 43-47

Nebria (Sadonebria) tenuicaulis sp. nov.

Figs 1, 2 , 5, 7, 9, 11

Diagnosis. Externally similar to the sympatric species Nebria sadona ohdaiensis , but easily distinguished from it by squared and less convex elytra ( Figs 1–4 ).

Description. Length of body (measured from the apices of the mandible to the elytral end): ♂, 11.0– 13.7 mm (mean±SD: 12.3± 0.77 mm) n=11; Ψ, 12.6–14.2 mm (mean±SD: 13.5± 0.52 mm) n=19. Dorsal surface of body black and shiny; pronotal and elytral margins dark brown; appendages reddish to dark brown; femora blackish brown ( Figs 1–2 ).

Head widest at mid­eye level, slightly longer than wide, with length from mandible apex to neck base 1.04 times longer than width between eyes; mandible stout, sharply arcuate at apex, with smooth surface; labrum 6­setose, with apical margin slightly emarginate; frontal impressions large and shallow, with surface markedly wrinkled; eyes large and fairly convex, with hind posterior margin behind a pair of supraorbital seta; tempora short and not swollen; mentum tooth bifid; mentum with three pairs of setae: one at apices of mentum tooth, one at middle part of mentum, and one at posterolateral margins; submentum with four pairs of setae. Antennae long, with apices reaching apical 1/3 of elytra in males, 1/ 2 in female; segments 1–8 without pubescence; one seta on apical 1/5 of segment 1 and longer than the segment; segment 2 short, with length 1/2 that of segment 1 and 1/3 that of segment 3; one seta on ventrolateral side of segment 2.

Pronotum (Fig. 5) cordate, widest at apical 1/3, with length 0.75 times longer than wide; anterior margin bisinuate, 1.14 times wider than posterior margin; posterior margin almost straight; lateral margins arcuate anteriorly at apical 1/3, almost straight at basal 2/3, slightly sinuate right before hind angle; anterior angles notably produced, with corner rounded; hind angle right­ to acute angled, with tip narrowly rounded; marginal setae two pairs, anterior one at apical 1/3 and posterior one slightly before hind angle; lateral margins wrinkled between marginal setae, fairly reflexed at basal 2/3, weakly reflexed at apical 1/3; surface with punctations at anterior and posterior margins and laterobasal impressions; laterobasal impressions large and fairly deep at posterior part, with the anterior part shallow and almost reaching apical half of the pronotum; laterobasal impressions on both sides connected by deep transverse line; median line impressed at middle part, absent near the anterior and posterior margins.

FIGURES 5–10. Pronotum (5, 6), and male (7, 8) and female (9, 10) genitalia. 5. N. (S.) tenuicaulis (holotype); 6. N. (S.) sadona ohdaiensis (holotype); 7. N. (S.) tenuicaulis (“Mt. Ohdaigahara” in NSMT); 8. N. (S.) sadona ohdaiensis (holotype); 9. N. (S.) tenuicaulis (Yama­no­ie­kita); 10. N. (S.) sadona ohdaiensis (Motokidani Valley) . a. aedeagus (right lateral view); b. right paramere (right lateral view); c. left paramere (left lateral view); d. apex of aedeagus (left lateral view); e, female genitalia (ventral view); f, spermatheca (dorsal view); va. vagina; sp. spermatheca; mo. median oviduct. Scales: 0.5 mm.

Elytra convex, 1.7 times longer than wide, widest behind middle; shoulders rounded; apices rounded; intervals convex, with microsculpture forming isodiametric meshes; scutellar stria present, not connected to stria 1; interval 1 usually with one dorsal pore at level of basal 1/5 of scutellar stria; some specimens with additional irregularly located pores; five to six dorsal pores on interval 3; hind wings reduced.

Gula smooth; prosternum sparsely and shallowly punctate; episternum and lateral sides of meta­sternum densely and deeply punctate; sterna 2–7 almost smooth except for lateral sides; lateral sides of sterna 2–7 with irregular small concavities, rugae, and punctations. Legs slender; hind tarsomeres with four to six setae on ventrolateral margins.

Aedeagus (Fig. 7a) slender and strongly arcuate; apical part spatulate, twice longer than broad. Right paramere (Fig. 7b) bent almost to basal half, spatulate, with apical part narrow. Left paramere (Fig. 7c) spatulate, shorter than right one, with apical part broad. Endophallus ( Fig. 11 ) straight, cylindrical, directed almost dorsally, with gonopore opening dorsally; with a pair of small, convex lobes on laterobasal sides; with small lobe on dorsobasal surface; apex of dorsobasal lobe narrow; dorsal surface near gonopore broadly swollen. Vagina (Fig. 9) without conspicuous pigmentation; with two pairs of appendices on middle part of ventral surface; spermatheca elongated.

Holotype. ♂, Mt. Tomoedake, Mt. Ohdaigahara, Kamikitayama­mura, Nara, Japan, 16–18. viii. 2004, K. Kubota, N. Kubota & H. Ikeda leg., ( FZUT 0012) [ FZUT].

Paratypes. 1♂ 1Ψ, “Mt. Ohdaigahara 1600 m. Nara Pref. 6–IX–1977 S. Kasahara leg.” [ NSMT]; 9♂ ɗ18ΨΨ, Mt. Ohdaigahara (3♂ ɗ4ΨΨ, Mt. Tomoedake; 3♂ 3Ψ, Motokidani Valley; 3♂ ɗ11ΨΨ, Yama­no­ie­kita), Kamikitayama­mura, Nara, Japan, same date and collectors as holotype [ FZUT, HUM, NIAES, NMSM and NHM].

Etymology. The specific name is a noun in apposition and derives from the Latin adjective tenuis, ­e (thin, slender) and the Latin noun caulis, ­is, m (a penis). It refers to the slender shape of the male genitalia.

Figures

FIGURES 1 – 4. Habitus (dorsal view). 1 – 2. N. (S.) tenuicaulis (1, holotype male; 2, paratype female from Mt. Tomoedake); 3 – 4. N. (S.) sadona ohdaiensis (3, holotype male; 4, female from Yama­no­ie­kita). Scales: 2.0 mm.

FIGURES 11 – 17. Endophalli of Sadonebria (11 – 16) (left lateral view, ventral view) and Orientonebria (17) (left lateral view, ventral view, right lateral view). 11. N. (S.) tenuicaulis (Motokidani Valley); 12. N. (S.) sadona ohdaiensis (Motokidani Valley); 13. N. (S.) sadona leechi; 14. N. (S.) niitakana; 15. N. (S.) saeviens (Mt. Kinpoku­san); 16. N. (S.) chinensis; 17. N. (O.) coreica. Numbers in square brackets indicate characters in Appendix 2. Scales: 0.5 mm.