Polyzonus (Striatopolyzonus) tonkinensis, Vives, Eduard & Pham, Hong Thai, 2017

Vives, Eduard & Pham, Hong Thai, 2017, New species of Callichromatini Swainson, 1840. (Coleoptera, Cerambycidae). New Cerambycidae from Vietnam. Part 6, Zootaxa 4236 (1), pp. 194-200 : 199

Polyzonus (Striatopolyzonus) tonkinensis sp. nov.

(Fig. 3)

Material studied. Holotype female 30 mm long and 6 mm wide, originating from Vietnam, Pia Oac, 23-30.V.2011, E. Vives & S. Lingafelter leg. ( EVC) . Paratype, 2 female, Vietnam, Tam Dao , IV.2013, local collector ( USNM, EVC) .

Description. Size: 30–32 mm. General colour of teguments golden green except for posterior part of head, pronotum and fore-femora which are metallic blue. Underside of body golden green and clothed in short grey tomentum. Greenish elytra with discal area blue along suture, shoulders and apical area golden. Legs and antennae black except for profemora.

Long narrow head, forming a quadrate rostrum at its anterior border. Large bulging eyes, microfaceted, contiguous antennal bases separated by a longitudinal groove. Short slender antennae, almost reaching elytral apex in females, scape robust and strongly punctate. Third antennomere slightly longer than 4th and 5th together, after 4th antennomere all segments are carinated, clothed in short black tomentum. Pronotum subquadrate (55/60), anterior and posterior border sinuate. Entire surface of pronotal disc covered in transverse grooves that converge in a central longitudinal line. Arched sides bearing a strong lateral protuberance, bordered and smooth at apex. Wide short prosternum, clothed in grey tomentum reaching prosternal sutures. Prosternal process wide and bordered, widened posteriorly, procoxal cavities closed.

Scutellum triangular, rounded at posterior apex and grooved longitudinally. Elytra long and parallel, apex widely rounded. Humeri rounded and projecting, with a fold in interior part. Suture narrow and finely bordered, discal area weakly depressed. Epipleura long and slender, golden at base and remaining area green. Mesosternum and metasternum finely punctate, with short grey pubescence same as abdominal sternites. Legs long and slender with fore- and mid-femora dilated in middle, fore- and mid-tibiae short, longitudinally carinated on external side and clothed in golden tomentum distally. Hind femora long and slender, weakly widened at apical third, metatibiae long and compressed, clothed in short black tomentum. Fore- and mid-tarsi short and wide, hind-tarsi with first segment as long as remaining three together.

Diagnosis and remarks. This species is close to P. (Striatopolyzonus) luteonotatus (Pic, 1928) , from which it can be separated mainly by its larger size, black legs and antennae, and strongly grooved, quadrate pronotum. The discal area of its elytra is rather convex whereas the discal area of S. (S.) luteonotatus is depressed. The metatibiae of the new species are more dilated and flatter.

Etymology. The specific epithet refers to Tonkin, the Vietnam old region where the holotype was collected.