Gonioctena (Asiphytodecta) truncaticornis, Cho & Borowiec, 2016

Cho, Hee-Wook & Borowiec, Lech, 2016, Revision of theGonioctena flavoplagiata species-group (Coleoptera: Chrysomelidae: Chrysomelinae), with descriptions of two new species from China and Laos, Acta Entomologica Musei Nationalis Pragae 56 (2), pp. 755-768 : 766-767

Gonioctena (Asiphytodecta) truncaticornis sp. nov.

( Figs 5 , 10 , 27–29 )

Gonioctena (Asiphytodecta) flavoplagiata : SPRECHER- UEBERSAX & DACCORDI (2016): 476 (misidentification).

Type locality. Laos, Xiengkhouang Province, Nong Haet, 19°30′N 104°03′E.

Type material examined. HOLOTYPE: ♂, ‘ Laos-N, Xieng Khuang prov., Nong Haet, 19°30’N 104°03’E, J Bezděk leg., 29–31.v.2001 // HOLOTYPUS Gonioctena (A.) truncaticornis sp. n., Cho & Borowiec 2014’ ( NMPC).

Description. Measurements in mm (n = 1): length of body: 6.80; width of body: 4.50; height of body: 3.10; width of head: 1.90; interocular distance: 1.32; width of apex of pronotum: 2.20; width of base of pronotum: 3.92; maximum width of pronotum: 3.92; length of pronotum along midline: 1.80; length of elytra along suture: 5.05.

Body oval and strongly convex ( Fig. 5 ). Head largely blackish-brown. Mandibles dark reddish-brown, apex black. Maxillary palps blackish-brown. Antennomeres I–VI yellowish- -brown to dark brown, VII blackish-brown, VIII–XI black. Pronotum dark brown to blackish-brown, margins black. Scutellum dark brown, basal margin black. Elytra dark brown to blackish-brown, with two pairs of yellowish-brown spots. Venter blackish-brown to black, with hypomera and last abdominal ventrite dark brown. Legs dark brown, with femora largely blackish-brown.

Head. Vertex weakly convex, covered with sparse punctures, becoming coarser and denser toward sides. Frontal suture V-shaped, reaching anterior margin, coronal suture rather long. Frons flat, suddenly depressed at anterior margin, covered with dense punctures. Clypeus very narrow and trapezoidal.Anterior margin of labrum with tooth-like projection. Mandibles with two sharp apical teeth and deep excavation for apical maxillary palpomere on outer side. Maxillary palps 4-segmented, with apical palpomere slightly widened, truncate apically. Antennae reaching pronotal base; antennomere I robust, longest; II as long as III; III longer than IV; antennomeres VIII–XI strongly widened and flattened, VIII–X each distinctly wider than long, XI rather truncate apically, about 0.84 times as long as wide ( Fig. 27 ).

Pronotum. Lateral sides rounded, widest at base, thence strongly narrowed anteriorly; anterior angles strongly produced ( Fig. 10 ). Anterior and lateral margins bordered, lateral margins barely visible in dorsal view. Trichobothria absent on both anterior and posterior angles. Disc covered with sparse or moderately dense punctures; lateral sides covered with much larger and denser punctures; interspaces covered with fine and sparse punctures. Scutellum distinctly wider than long, narrowed posteriorly.

Elytra. Lateral sides slightly widened posteriorly, widest beyond middle, thence roundly narrowed posteriorly. Humeral calli well developed. Disc covered with irregular, coarse and large punctures except humeri, elytral suture and lateral margins; punctures partially arranged in double rows; interspaces covered with fine and sparse punctures. Epipleura visible in lateral view except near base. Hind wings well developed.

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

Legs. Moderately robust. Tibiae widened apically, with tooth-like projection. Fore legs with tarsomere I slightly narrower than III. Tarsal claws appendiculate.

Genitalia. Aedeagus very long and thin, moderately narrowed from middle to apical 1/5, setose apicolaterally, with apical process long, weakly widened before apex in dorsal view; moderately sinuate in lateral view ( Fig. 28 ).

Differential diagnosis. Gonioctena (A.) truncaticornis sp. nov. is similar to G. (A.) eburoides , G. (A.) flavoplagiata , G. (A.) jindrai sp. nov., and G. (A.) mausonensis in strongly widened and flattened last four antennomeres and two pairs of yellowish brown spots on dark elytra. However, the new species can be easily distinguished by truncate apex of last antennomere and very long and thin aedeagus.

Etymology. The species is named after the truncate apex of its apical antennomere.

Distribution. Laos: Xiengkhouang ( Fig. 29 ).

Figures

Figs 1–5. Dorsal habitus: 1 – Go- nioctena (A.) eburoides (Achard, 1924); 2 – G. (A.) flavoplagiata (Jacoby, 1890), lectotype; 3 – G. (A.) jindrai sp. nov., holotype; 4 – G. (A.) mausonensis Cho & Borowiec, 2016, holotype; 5 – G. (A.) truncaticornis sp. nov., ho- lotype. Scale bars = 1.0 mm.

Figs 6–10. Head and pronotum: 6 – Gonioctena (A.) eburoides (Achard, 1924); 7 – G. (A.) flavoplagiata (Jacoby, 1890), lectotype; 8 – G. (A.) jindrai sp. nov., holotype; 9 – G. (A.) mausonensis Cho & Borowiec, 2016, holotype; 10 – G. (A.) truncaticornis sp. nov., holotype. Scale bars = 1.0 mm.

Figs 22–28. 22–24 – Gonioctena (A.) jindrai sp. nov.: 22 – antenna; 23 – aedeagus, holotype (dorsal view, detail of apex in dorsal view and lateral view); 24 – spermatheca. 25–26 – G. (A.) mausonensis Cho & Borowiec, 2016 (after CHO & BOROWIEC 2016): 25 – antenna; 26 – aedeagus, holotype (dorsal view, detail of apex in dorsal view and lateral view). 27–28 – G. (A.) truncaticornis sp. nov.: 27 – antenna; 28 – aedeagus, holotype (dorsal and lateral views). Scale bars = 1.0 mm (except Fig 24 = 0.5 mm).

Fig. 29. Distribution of Gonioctena (A.) flavoplagiata species-group.