Gonioctena (Gonioctena) amurensis Cho & Borowiec

Cho, Hee-Wook, Kippenberg, Horst & Borowiec, Lech, 2016, Revision of the Gonioctenanivosa species-group (Coleoptera, Chrysomelidae, Chrysomelinae) in the Holarctic region, with descriptions of two new species, ZooKeys 596, pp. 87-128 : 89-90

Taxon classification Animalia Coleoptera Chrysomelidae

Gonioctena (Gonioctena) amurensis Cho & Borowiec sp. n. Figs 1-2, 13-15, 16

Type material.

Holotype: ♂ (ZIN), Russia, Amur Oblast, Svobodnensky District, between the Malaya Pera and Bolshoy Ergel Rivers, 2.VII.1958, Zinoviev leg. // HOLOTYPUS Gonioctena (Gonioctena) amurensis sp. n. Cho & Borowiec 2015. Paratypes: 5♂♂ (ZIN), same data as holotype; 1♂, 1♀ (ZIN), Russia, Amur Oblast, Svobodnensky District, Klimoutsy Village, 40 km W Svobodny City, 14.VII.1957, Zinoviev leg.; 1♂ (ZIN), Russia, Amur Oblast, Tyndinsky District, between Djeltulak and Sosnovaya, 30.VII.1928, Obolenskiy leg.; 1♂ (NHMB), Russia, Primorsky Krai, Ussuriysk Reserve, VI.1956, L.N. Medvedev; 1♂ (TLMF), Russia, Primorsky Krai, Khasansky District, Kedrovaya Pad Nature Reserve, 1956, L. Medvedev; 1♀ (NHMB), Mongolia, Central Aimak, 21.VI.1974, V. Janovsky leg. Each paratype specimen has a type label: PARATYPUS Gonioctena (Gonioctena) amurensis sp. n. Cho and Borowiec 2015.

Diagnosis.

Gonioctena amurensis sp. n. is closely related to Gonioctena jani sp. n. in having small body size and similar length of antennae, however it can be distinguished by pronotum with small and moderately dense punctures on median region and large and dense punctures on lateral region (sparse punctures on median region and moderately dense punctures on lateral region in Gonioctena jani sp. n.) and rather thin aedeagus with relatively long apical process (rather thick with relatively short apical process in Gonioctena jani sp. n.).

Description.

Measurements in mm (n = 5): length of body: 5.00-5.50 (mean 5.16); width of body: 2.90-3.25 (mean 3.09); height of body: 1.85-2.30 (mean 2.09); width of head: 1.40-1.45 (mean 1.41); interocular distance: 0.95-1.05 (mean 0.99); width of apex of pronotum: 1.50-1.65 (mean 1.55); width of base of pronotum: 2.45-2.60 (mean 2.51); maximum width of pronotum: 2.52-2.62 (mean 2.56); length of pronotum along midline: 1.30-1.40 (mean 1.32); length of elytra along suture: 3.65-4.10 (mean 3.85).

Body oblong oval and moderately convex (Fig. 1). Head black. Mandibles black, with reddish brown band near apex. Maxillary palps reddish brown or dark brown, with apical palpomere blackish brown. Antennomeres 1-7 yellowish brown, 1 and 7 darkened, 8-11 dark brown to blackish brown. Pronotum reddish brown, with 2-3 obscure spots or an obscure marking (Fig. 15). Scutellum black. Elytra reddish brown, with 3-5 pairs of black spots. Venter black, with hypomera and apical margin of last abdominal ventrite reddish brown. Legs black, with tibiae except base and tarsi reddish brown.

Head. Vertex weakly convex, covered with coarse and dense punctures. Frontal suture V-shaped, coronal suture absent or weak. Frons flat, strongly depressed anteriorly, covered with moderately dense punctures. Clypeus narrow and trapezoidal. Anterior margin of labrum distinctly concave. Mandibles with 2 sharp apical teeth and a deep excavation for apical maxillary palpomere at outer side. Maxillary palps 4-segmented, with apical palpomere distinctly widened, truncate apically in male; slightly widened in female. Antennae in male as long as half length of body; antennomere 1 robust; antennomere 2 shorter than 3; antennomere 3 longer than 4; antennomeres 7-11 each distinctly longer than wide; antennomere 11 longest, about 2.48 times as long as wide (Fig. 13). Antennae in female almost reaching elytral humeri; antennomere 11 about 2.38 times as long as wide.

Pronotum. Lateral sides widest near base, roundly moderately narrowed anteriorly, anterior angles strongly produced (Fig. 2). Anterior and lateral margins bordered, lateral margins invisible in dorsal view. Trichobothria present on posterior angles. Disc covered with moderately dense punctures; lateral sides covered with much coarser and denser punctures, becoming larger toward base, partially confluent near basal margin; interspaces covered with fine and sparse punctures. Scutellum slightly wider than long, narrowed posteriorly.

Elytra. Lateral sides moderately widened posteriorly, widest beyond middle, thence roundly narrowed posteriorly. Humeral calli well developed. Disc covered with 11 regular rows of large punctures, including a short scutellar row; punctures rather irregular between 6th and 8th striae in apical half; interspaces shagreened, covered with fine and sparse punctures. Epipleura wholly visible in lateral view. Hind wings well developed.

Venter. Hypomera weakly rugose, with a few punctures near anterolateral corners of prosternum. Prosternum covered with coarse and dense punctures bearing long setae; prosternal process enlarged apically, bordered laterally, with moderately dense punctures. Metasternum covered with small and moderately dense punctures in median region, large and dense punctures in lateral region. Abdominal ventrites covered with dense punctures bearing short setae.

Legs. Moderately robust. Tibiae widened apically; fore tibia with a blunt tooth-like projection; mid and hind tibiae each with a tooth-like projection. Fore legs with tarsomere 1 strongly enlarged, distinctly wider than 3 in male; slightly narrower than 3 in female. Tarsal claws appendiculate.

Genitalia. Aedeagus moderately narrowed apically, with apical process rather long, very slightly tapered apically, apex truncate in dorsal view; moderately curved, with apical process pointed and slightly bent downward at apex in lateral view (Fig. 14). Spermatheca absent.

Etymology.

Named after the type locality, Amur region.

Distribution.

Mongolia, Russia (Far East) (Fig. 16).