Amamiclytus nobuoi nobuoi Ohbayashi, 1964

Niisato, Tatsuya & Han, Chang-do, 2011, A revision of the genus Amamiclytus Ohbayashi from Taiwan and the Ryukyu Islands (Coleoptera, Cerambycidae), ZooKeys 118, pp. 19-52 : 26-30

Amamiclytus nobuoi nobuoi Ohbayashi, 1964 Figs 36 –73441– 46

Amamiclytus nobuoi Ohbayashi, 1964: 21, pl. 4, fig. 1; type locality: Hatsuno, Amami-Ôshima.

Amamiclytus hirtipes : Kojima et al. 1965: 85. (nec Matsushita 1940)

Amamiclytus nobuoi nobuoi : Niisato 2007: 502.

Description.

Male and female. Body length (from vertex to elytralapices) 4.0-5.1 mm in ♂, 4.0-4.9 mm in ♀. Colour black, glossy in general, distinctly so on elytra, dark brown in antennae, meso- and metathoraces, abdomen and legs except for pale brown tibiae and yellowish brown tarsi, mouthparts except for black mandibles yellowish brown. Body moderately clothed with fine pale pubescence, sparsely with erect long pale hairs on clypeus, genae, near pronotal base, abdominal ventrites and hind tibiae; head sparsely with pale hairs, largely exposing disc, scattered with a few erect long pale hairs, very thinly with pale gray pubescence on frons in both sexes; antennae distinctly with long pale brown hairs along undersides of segments 2-5; pronotum largely exposing disc, thinly pubescent, with a few erect long pale hairs, Pb at sides transverse, slightly narrowed inwards; scutellum hardly pubescent; elytra sparsely with pale pubescence, without long erect pale hairs, B very sparse, barely recognized, S on basal eighth small and longitudinally oblong, La on basal third semicircular, slightly oblique, Lp on apical third, almost complete though narrow, weakly arcuate, A moderately dense; prosternum moderately with white pubescence near basal 2/3, Msl distinct, Mss almost absent, Mta very sparse along posterior margin of metasternum, dense and entire on apical 2/5 of metepisternum; V1 and V2 dense, narrowed to middle.

Head across eyes almost as wide as pronotum, HW/PW 0.80-1.06 (M 0.95) in ♂, 0.89-0.95 (M 0.92) in ♀; frons as long as wide, arcuately dilated apicad, with a fine but deep smooth median line, closely roughly punctured; clypeus almost flattened; vertex raised towards antennal cavities which are separated from each other by about half the width of occiput; occiput distinctly convex, sparsely punctured. Antennae thin and long, gradually thickened apicad, attaining apical third in ♂ or 3/5 in ♀ of elytra; scape almost cylindrical, 3rd segment 1.4-1.8 times as long as 4th segment, middle segments weakly thickened at apices, terminal segment short, rounded at apex in ♂.

Pronotum slightly longer than wide, strongly arcuate at sides; PL/PW, 1.18-1.38 (M 1.27) in ♂, 1.09-1.20 (M 1.13) in ♀, PB/PA 0.92-1.00 (M 0.95) in ♂, 0.87-1.00 (M 0.92) in ♀, EL/PL 2.40-3.00 (M 2.68) in ♂, 2.67-3.11 (M 2.92) in ♀, PW/EW 0.76 -0.91 (M 0.83) in ♂, 0.79-0.82 (M 0.80) in ♀; disc moderately convex though slightly depressed above, provided with large shallow punctures, though densely finely punctured in apical half in ♂. Scutellum regular triangular, slightly acute at apex.

Elytra relatively long and slender, EL/EW 2.73-2.86 (M 2.78) in ♂, 2.55-2.80 (M 2.64) in ♀; sides with almost rounded humeri, gently arcuate at a level between basal fourth and apical half, then gently arcuate and narrowed to oblique apices, without any dent at inner and outer angles; disc almost evenly convex, sparsely provided with fine shallow punctures.

Ventral surface almost smooth, provided with a few coarse punctures on prosternum, minute ones on meso- and metathoraces and abdomen; ♂ anal ventrite 3/5 the length of basal width, weakly arcuate at apical margin.

Legs slender, rather long; hind legs 1.4-1.7 times as long as elytra, with femur strongly swollen in apical half, slightly exceeding elytral apex, 1st tarsal segment 1.6-2.0 times as long as the following two segments combined.

Male genitalia. Median lobe about 2/5 the length of elytra, slender and elongate; dorsal plate slightly wider than ventral plate in apical eighth, distinctly narrowed to apex which is rounded; ventral plate almost parallel-sided in basal half, then strongly narrowed to apex which is strongly pointed at the extremity, slightly reflex in profile; median struts slender, almost half the length of median lobe. Endophallus densely provided with minute spinous spicules behind crescent-like sclerites at a level between basal 2 /5 and 4/5, densely covered with minute serrate spicules on apical sixth. Tegmen elongate, slightly shorter than median lobe; parameres more or less elongate, nearly 2/5 the length of tegmen, divided in apical fourth, gently arcuate in external margins, arcuately emarginate in inner margins, almost rounded at apices which are provided with numerous short and a few long setae; basal ridge slightly raised; ring part almost parallel-sided in basal third. Eighth tergite slightly elongate, semicircular, gently narrowed apicad in apical fourth, with apical margin weakly arcuate, provided with numerous short and a few long setae. Eighth sternite very small, distinctly transverse, almost 1/3 the length of median lobe, with apical margin almost transverse, deeply concave at middle.

Female genitalia. Coxite lobe ovoid, scattered with short and long setae. Stylus almost half in length to coxite lobe, elongate, weakly dilated apicad. Bursa copulatrix small, weakly constricted near base. Spermatheca narrow, gently arcuate, weakly broadened apicad; gland thin, attached near apical third; duct thin, strongly coiled throughout.

Specimens examined.

1♀ (holotype), Hatsuno, Amami-Ôshima, 10 –VII– 1962, N. Ohbayashi leg. (EUMJ); 2♀♀, Hatsuno, Amami-Ôshima Is., Kagoshima Pref., 28 –VI– 1970, K. Sakai leg.; 1♂, 1♀, same locality, 24 –VI– 1970, T. Kobayashi leg.; 1♂, 1♀, same locality, 19 –VI– 1971, H. Yokoyama leg.; 1♂, same locality and collector, 29 –VI– 1971; 1♀, same locality and collector, 30 –VI– 1971; 1♀, same locality, 6 –VII– 1973, M. Ito leg.; 1♂, same locality, 6 –VII– 1975, K. Kuzugami leg.; 1♂, Chûô–Rindô, Naze City, Kagoshima Pref., 30 –VI– 2001, T. Kurihara leg.; 1♀, Ôganeku, Yamato Village, Ôshima Gun, Kagoshima Pref., 30 –VI– 2003, T. Kurihara leg.

Geographical distribution.

Amami Isls. ( Amami-Ôshima Is.), Ryukyus, Japan.

Comments.

The nominotypical subspecies of Amamiclytus nobuoi Ohbayashi is endemic to the Amami-Ôshima Isls., mid-Ryukyus of Southwest Japan. The adult beetles mainly appear in summer between mid June and early July, and are often found on tree blossoms. The larvae bore in freshly dead twigs of Rhaphiolepis indica var. umbellata and Machilus thunbergii (Niisato, 2007). Though not so rare until 1970's, only a few specimens of Amamiclytus nobuoi nobuoi have been collected since the 1980's. This clytine has been recently treated as "Data Deficient", a category of endangered animals in the Japanese Red Data Book (Ministry of the Environment, Japan, 2007).

This species is somewhat similar in external morphology to Amamiclytus setiger sp. n. from Taiwan, but can be easily distinguished from the latter by the elytra lacking erect long pale hairs and quite different structure of the male genitalia.