Rhyzodiastes (Temoana) xii , Wang, Cheng-Bin, 2016

Wang, Cheng-Bin, 2016, Rhyzodiastes (Temoa na) xii sp. nov. (Coleoptera: Rhysodidae: Clinidiini), a new species from Hainan Island, China, Zootaxa 4126 (2), pp. 287-294: 289-294

publication ID


publication LSID


persistent identifier


treatment provided by


scientific name

Rhyzodiastes (Temoana) xii

sp. nov.

Rhyzodiastes (Temoana) xii  sp. nov.

( Figs. 1View FIGURE 1 A–F; 2 A–G; 3 A–C; 4 A–E)

Material examined. Holotype: Ƌ, CHINA, Hainan: Jianfengling, main peak, 1000 m, rotten wood, individually collected, 25.XI. 2008. Paratypes: 1 Ƌ, same data as holotype except: 620 m, cow dung; 1 ♀, Baoting County, 14.IV. 2015, Lu Qiu leg.

Description. Male holotype. Medium size, TL: 6.56 mm. Length of different body parts: HL: AL: PL: ELL = 1.02: 1.64: 1.78: 3.67 mm; width: HW: PW: ELW = 0.95: 1.22: 1.44 mm.

Habitus ( Figs. 1View FIGURE 1 A, B) elongate, rather narrow, and lustrous. Body colour mostly blackish brown to black; antennae and legs somewhat reddish brown; mouthparts reddish brown to yellowish brown.

Head ( Figs. 2View FIGURE 2 A–C) only slightly longer than wide, HL / HW = 1.07. Median lobe short and triangular, with acute apex opposite middle of eyes. Antennal lobe glabrous, separated from median lobe. Temporal lobe 2.36 longer than wide; inner margins strongly curved, so at middle, temporal lobes are separated by less than half width of one of them; temporal lobe fringed with pilosity. Anterior tentorial pits and postantennal pits distinct. Postclypeal groove very narrow. Frontal space narrow anteriorly, becoming broad posteriorly. Frontal grooves narrow, pollinose in anterior part. Orbital groove narrow but complete, angulate opposite posterior margin of eye; one usual temporal seta present in orbital groove, posterior to eye. Eye entire, narrowly crescentic, EL / EW = 4.97, about half length of temporal lobe. Genae glabrous, posterior face of temporal lobe pilose.

Antenna ( Fig. 2View FIGURE 2 D) with stylet short, conical and subacute. Minor setae tufts present on antennomeres V–X. Basal setae absent, only antennomere X with one or two. Antennomere I dorsally pollinose, while other antennomeres almost without pollinosity.

Pronotum ( Fig. 2View FIGURE 2 E) elliptical, moderately elongate, widest around middle, PW / PL = 1.46. Sides evenly curved, both ends distinctly narrowed. Median groove with moderate width, as wide as median pits; anterior median pit with subequal width to posterior median pit; posterior median pit displaced anteriorly, with anterior end at 3 / 8 of pronotal length before basal margin; median groove deep but slightly narrowed after posterior median pit, with sides glabrous; median groove in and between median pits glabrous medially, but with pollinose lateral scarps. Inner carina convex, with lateral margin gradually sloping into paramedian groove. Paramedian groove laterally bounded by pollinose strip on vertical medial scarp of outer carina; inner margin of outer carina curved, slightly undulating; basal impression small, narrowly closed posteriorly, connected to margin by pollinose strip. Outer carina moderately narrow, slighly tapered anteriorly. Marginal groove fine, impressed, linear and complete; visible in dorsal view as is margin laterad to it. Submarginal groove nearly complete, becoming finely pollinose posteriorly. Pronotal setae absent. Notopleural suture slightly pollinose. Sternopleural groove absent. Pleural groove incurved and pollinose. Ventral surface of prothorax opalescent.

Elytra ( Figs. 1View FIGURE 1 A; 2 F) elongate, widest at about apical 3 / 8, ELL / ELW = 2.54. Elytron pilose around scutellar pits, extending laterally to base of Interval II, but broadly interrupted in Interval III. Sutural interval flat. Sutural stria impressed, faintly punctate and finely pollinose, with apex laterally curved at apical 1 / 5 of elytron to join parasutural stria. Interval II convex, sloped laterally. Parasutural stria deep, its lateral wall a medially directed scarp, its apical part incurved, posterior its pollinosity combining with that of intratubercular stria, and the combined strip continuing across anterior face of apical tubercle up to suture. Interval III slightly convex, its apex forming scarcely dilated subapical tubercle, which separated by 3.17 width of one of them. Intratubercular stria impressed, pollinose, dilated. Interval IV slightly convex, continuous with moderately swollen apical tubercle. Marginal stria entire, impunctate, deep. Submarginal stria impressed, ending after base of sternum VI. (Because most of the elytral setae are missing in examined specimens, I abandon describing them.) Elytral cauda absent. Metathoracic wings vestigial.

Profemur ( Fig. 3View FIGURE 3 A) with a low and subacute tooth on ventral side. Meso- & metatibia ( Figs. 3View FIGURE 3 B, C) with two unequal spurs, and one small, protrudent, subacute calcar respectively. Pro- & metatrochanter with round apex.

Ventral surfaces of pterothorax and abdomen ( Fig. 2View FIGURE 2 G) opalescent. Metasternum with complete median sulcus. Abdominal Sterna I & II with flattened, microsculptured median area. Sterna III–V with large lateral pits and medially interrupted pollinose transverse sulci. Sternum VI without any tubercles, and with widely interrupted transverse sulci, each joined to apices of submarginal sulcus.

Genital segment as shown in Fig. 4View FIGURE 4 E, with handle moderately long and narrowly rounded at tip. Aedeagus as shown in Figs. 4View FIGURE 4 A–C, with median lobe very slender and tubular. Male paratype ( Figs. 1View FIGURE 1 C, D; 4 D). Much smaller than holotype, but there are no remarkable differences on external and aedeagal characters between them. The small body size is probably due to malnutrition during larval stage.

Female paratype ( Figs. 1View FIGURE 1 E, F). Similar to male in general appearance. Meso- & metatibia without calcars. Sternum IV with lateral pits distinctly larger than that on sterna III & V. Sternum VI with transverse sulci dilated laterally.

Etymology. The specific epithet is dedicated to Dr. Xi Jin-Ping, the President of the People's Republic of China, for his leadership making our motherland stronger and stronger.

Distribution. China (Hainan).

Diagnosis This new species well resembles R. (T.) rimoganensis (Miwa)  in general appearance, but it is easily to distinguish it from the latter by the combination of the following characteristics: in R. (T.) xii  sp. nov., antenna without basal setae (only antennomere X with one or two), pronotal anterior median pit with subequal width to posterior median pit, metasternum with median sulcus, sternum VI without any tubercles; while in R. (T.) rimoganensis (Miwa)  , antenna with sparse basal setae on antennomeres VIII–X, pronotal anterior median pit wider than posterior median pit, metasternum without median sulcus, sternum VI with a pair of tubercles.

Additionally, for members in the R. (T.) singularis  species-group, only the new species and R. bipunctatus Bell & Bell  have complete median sulcus on metasternum, but it is easily to distinguish them from the Key 3 above.