Nippononebria changbaiensis Kavanaugh & Liang, 2010

Kavanaugh, David H. & Liang, Hongbin, 2010, A new species of genus Nippononebria Uéno (Coleoptera, Carabidae, Nebriini) from Changbai Mountain, Jilin Province, China, the first species of the genus confirmed from the Asian mainland, ZooKeys 46, pp. 1-13 : 3-9

Nippononebria changbaiensis Kavanaugh & Liang , sp. n.

urn:lsid:zoobank.org:act:22DAD7F4-EBAE-4C8C-9296-DDD1B823D02E

Figs. 1–5

Type locality. PEOPLES REPUBLIC OF CHINA, Jilin Province, Changbai Mountain, 42.034004°N, 128.055854°E

Type material. Holotype, a male, deposited in IOZ, labeled: “ Jilin Province, Changbaishan, Tianchi, waterfall, 2000–2600m, Chinese Academy of Sciences ” [partly in Chinese]/ “ 1987.VII.22, Guiyun Deng collector” [partly in Chinese] / ” HOLO- TYPE Nippononebria changbaiensis Kavanaugh & Liang sp. n. designated 2010 ” [red label] ( Fig. 2A ). Paratype, a male, deposited in CAS, labeled: “ Jilin Province, Changbaishan, Tianchi, 2000m, Chinese Academy of Sciences ” [partly in Chinese]/ “ 1987. VII.22, Peiyu Yu collector” [partly in Chinese]/ ” PARATYPE Nippononebria changbaiensis Kavanaugh & Liang sp. n. designated 2010 ” [yellow label] ( Fig. 2B ).

Etymology. The species epithet is an adjective in the nominative singular derived from the name of the type locality, Changbai Mountain, and referring to it.

Diagnosis. Adults of this species can be distinguished from those of all other species of subgenus Nippononebria by the following combination of character states: size very small (SBL of male less than 6.5 mm); head, pronotum, and elytra shiny, with faint but distinct blue-green metallic reflection; pronotum relatively short and broad, distinctly wider than head across eyes, ratio of pronotal width to length = 1.4–1.5, basal margin distinctly wider than apical margin, with basal sinuation of lateral margin long and shallow, basal angles rectangular, lateral explanation narrow anteriorly and at middle, markedly broadened basally; elytral silhouette subovoid, relatively short, widest distinctly anterior to middle, elytral microsculpture comprised of moderately impressed and markedly transverse meshes, humeral carina and tooth slightly developed, striae markedly punctate, intervals very slightly and smoothly convex; hindwings full-sized; thorax coarsely punctate ventrally (most distinctly so on mesepisterna and metepisterna, but also on prosternum and proepisterna anteriorly, on mesosternum, and on metasternum laterally).

Description. Body ( Fig. 1 ) size very small for a Nippononebria or a nebriine, SBL males 5.8–6.0 mm; head piceous or reddish brown, without pale spot or spots on vertex, pronotum and elytra piceous or reddish-brown, legs brown or reddish-brown, venter brown or reddish-brown; dorsum with faint but distinct metallic blue-green reflection (most evident on elytra), venter without metallic reflection; frons smooth or slightly punctate laterally, vertex smooth or nearly so; head slightly shiny, pronotum and elytra markedly shiny, microsculpture on frons and pronotum faintly impressed with sculpticells comprised of broken isodiametric meshes, microsculpture on elytra moderately impressed with sculpticells comprised of markedly transverse meshes.

Head. Size and width relative to pronotum average for genus. Genae and occiput not inflated, head very slightly constricted behind eyes. Eyes medium in diameter and convexity for genus. Vertex with one pair of supraorbital setae. Antennae moderately elongate; scape slightly short and slightly arcuate, markedly narrowed basally, with one anterodorsal seta subapically; pedicel with one ventral seta subapically; flagellar antennomeres moderately elongate, medium width, antennomeres 3 and 5 subequal in length, antennomere 4 with apical one-third distinctly pubescent, antennomeres 5 to 11 distinctly pubescent. Labrum with apical margin truncate or slightly concave, with four or five setae. Clypeus with apical margin truncate or slightly concave. Glossal sclerite (ligula) with apicoventral margin moderately and bluntly toothed, with one pair of ligular setae apicoparamedially; paraglossae separate, minute, dentiform. Labium with penultimate labial palpomere trisetose anteriorly, minutely unisetose posteroapically. Submentum with two pairs of lateral setae and one pair of medial setae.

Pronotum. Size relative to elytra large, markedly wide, and slightly short for genus; shape ( Fig. 3 ) subquadrate, markedly convex, basal margin distinctly wider than apical margin; lateral margins slightly arcuate, with basal sinuation long and shallow; lateral explanation present throughout pronotal length, narrow anteriorly and at middle, markedly broadened basally; basal margin straight; apical angles moderately long, slightly narrow, and moderately rounded; basal angles rectangular or slightly acute, not projected posteriorly, not apically dentate; lateral margination (also called “lateral bead”) uniformly present throughout, moderately wide and moderately impressed; anterior margination present in lateral 30–40%, absent medially, moderately wide and moderately impressed; anterior transverse impression broad and slightly shallow; posterior transverse impression narrow and very deep; basal foveae deep, extremely broad, slightly divergent basally, without or with a faint and broad tubercle medially; one pair each of midlateral and basolateral setae present.

Thoracic venter. Prosternal intercoxal process moderately lanceolate, smooth, with margination of intercoxal process present and complete both laterally and apically, asetose. Prosternum and proepisternum sparsely and coarsely punctate anteriorly. Mesosternum sparsely punctate laterally. Metasternum slightly short, sparsely punctate laterally, margination of anterior intercoxal process complete, broad, and deeply impressed. Mesepisternum and metepisternum sparsely and coarsely punctate.

Elytra. Markedly shorter in relation to length of forebody than average for genus, moderately wide, moderately convex laterally and flattened medially; elytral silhouette ( Fig. 1 ) subrectangular, widest near basal one-third; basal marginations very long, straight or slightly concave; humeri angulate, slightly rounded, humeral carinae markedly distinct and sharp, moderately projected, humeral teeth present; subhumeral sinuation absent; subapical sinuation absent or very shallow; elytral apices at midline, bluntly pointed; elytral striae moderately deep, markedly punctate, scutellar striole short, extended independently from basal margination medial to stria 1; elytral intervals slightly convex, smooth, and without catenations, basal (parascutellar) setiferous puncture present, interval 3 with two or three setiferous pores, intervals 5 and 7 without setiferous pores, interval 9 with umbilicate series comprised of five to seven setiferous pores, all elytral setiferous pores barely evident or only faintly foveate.

Hind wings. Full-sized.

Legs. Medium length for genus; hind coxae with one seta basally and one seta apically. Hind trochanters kidney-shaped, medium length, truncate or broadly rounded apically. Middle tibiae with dorsal sulcus present, extended from near base to apical one-third, with brush of sparse setae present dorsosubapically. Tarsi with very sparse, minute setae dorsally; protarsi of males with basal three tarsomeres broadened and with pads of adhesive setae ventrally; hind tarsi with ventroapical margin of tarsomere 4 truncate.

Abdomen. Sternum II (first visible sternite) sparsely and coarsely punctate, other sterna impunctate; suture between sterna III and IV complete, distinct throughout; sternum III without setae; sterna IV to VI with one pair of posterior paramedial setae, without paralateral setae; sternum VII (last visible sternite) of males with one pair of posterior paramedial (“anal”) setae.

Male genitalia. Median lobe of aedeagus ( Fig. 4 A–B) with basal bulb rounded and markedly closed basally, dorsobasal piece present as a large, simple mid-sagital fin dorsally; mid-shaft moderately thick, slightly narrowed basally, with its axis bent to a slightly acute (<90 degrees) angle (in lateral aspect), circular (in cross-section), with right face of mid-shaft unmodified; preapical-shaft narrow and moderately tapered apically, ventral margin straight or slightly and smoothly concave (in lateral aspect), broad, slightly tapered basally and apically and faintly deflected right (in dorsal aspect), with apical orifice slightly deflected right (in apical aspect); apical lamella ( Fig. 4A ) short, narrow, narrowly rounded apically, nearly centered on preapical shaft (in ventral aspect), plane of lamellar face horizontal (in apical aspect). Parameres asymmetrical, with right slightly longer than left; right paramere ( Fig. 4C ) slender, more fully sclerotized apically but with more faintly sclerotized areas subapically on anterior and posterior margins; left paramere ( Fig. 4D ) broad, slightly narrowed and only faintly sclerotized apically.

Female genitalia. No female specimens are known.

Geographical distribution. This species is known only from the type locality, on Changbai Mountain, on the border between Jilin Province, China, and North Korea ( Fig. 5 ).

Habitat distribution. According to Professor Peiyu Yu (personal communication), the two known specimens of N. changbaiensis likely were collected under stones above treeline on the north slope of Changbai Mountain. Th ere is some difficulty, however, in determining the precise locations where these specimens were collected on the mountain. To the unaided eye, there is little remarkable about adults of this species, and they could readily be mistaken for adults of some Bembidion species (which would be both diverse and abundant in this area) rather than a nebriine; hence there would have been little reason for Professor Yu to mark their capture in memory. “Tianchi”, which appears on the labels for both specimens, means “mountain lake”, suggesting that they were collected near the lake that occupies the summit crater. The holotype label also mentions the “waterfall”, which is a well-known feature at the head of the valley leading to the rim of the summit crater and lake. Th e holotype’s label cites an elevation range of 2000–2600 m and the paratype’s label cites an elevation of 2000 m. The level of the lake shore is at about 2200 m elevation, the base of the waterfall at about 2000 m, and the top of the waterfall and floor of the upper valley leading directly to the lake at about 2200 m. We conclude that both specimens were probably collected under stones along the stream course that includes the large waterfall, perhaps both above and below that feature. We have used this feature to estimate the geographical coordinates specified in the type locality description.

Phylogenetic relationships. Based on characters of external morphology and form and structure of male genitalia, N. changbaiensis is clearly a member of genus Nippononebria and of the nominate subgenus. Th e very small body size, unusual body shape (especially the elytral silhouette), and thoracic venter coarsely punctate laterally distinguish members of this species from those of the Japanese species, as well as from members of all Vancouveria species. We found no features that suggest a closer relationship of N. changbaiensis to any one of the Japanese than to any other; it is probably the sister species to a clade including the three Japanese species of subgenus Nippononebria .

Geographical relations with most closely related species. The known geographical range of N. changbaiensis , confined to a single locality on the Asian mainland, is allopatric with respect to the ranges of the three other species of subgenus Nippononebria , all restricted to Japan ( Fig. 5 ). Nippononebria pusilla and N. sawadai occur only on Honshu Island (at high elevations in restricted parts of central and northern Honshu, respectively); and N. chalceola ranges more widely, and at lower elevations, on both Honshu and Kyushu Islands.

Figures

Figure 1. Holotype male, Nippononebria changbaiensis sp. n., dorsal habitus. Scale line = 1.0 mm.

Figure 2. Photographs of labels for type specimens of Nippononebria changbaiensis sp. n. A Holotype B Paratype.

Figure 3. Holotype male, Nippononebria changbaiensis sp. n., pronotum, dorsal aspect. Scale line = 0.5 mm.

Figure 4. Holotype male, Nippononebria changbaiensis sp. n., genitalia. A median lobe (aedeagus), ventral aspect B median lobe, left lateral aspect C right paramere, lateral aspect D left paramere, lateral aspect. Scale line = 0.5 mm.

Figure 5. Map of the Sea of Japan and adjacent land areas, showing the known geographical distribution of Nippononebria (sensu stricto) Uéno and included species: solid yellow circle N. changbaiensis sp. n. C N. chalceola (Bates) P N. pusilla (Uéno) S N. sawadai Nakane (n.b. Only exemplar localities shown for N. chalceola and N. pusilla). Scale line = 400 km.