Mecyclothorax timorensis, Baehr & Reid, 2017

Baehr, Martin & Reid, Chris A. M., 2017, On a Collection of Carabidae from Timor Leste, with Descriptions of Nine New Species (Insecta: Coleoptera, Carabidae), Records of the Australian Museum 69 (6), pp. 421-450 : 424-425

Mecyclothorax timorensis sp. nov. Baehr

Figs 1 , 11 , 18

Holotype ♂, “ TIMOR LESTE nr Desa Liurai, Hatubuilico Rd, 2.5k W t’off highwaY 8°52'41"S 125°34'36"E Euc. urophylla /grass/vacc[inium] woodland 24–28.v.2012 1850m J.Recsei TL2012/079/511 [pitfall traps]” K402558 ( AMS) . Paratypes (25): 4♂♂, 10♀♀, same data as holotYpe, K402556, K402560–570 ( AMS); K402557 , K402559 ( CBM) ; 1♂, 7♀♀, “ TIMOR LESTE Ramelau sum’t plat. 8°54'51"S 125°39'31"E 28/05/2012 stunted eucs/vaccinium/ moss/grass 2750m C. Reid grass tufting TL2012/090/575” K402543, K402546–547, K402549–552 ( AMS) , 1♀ K402548 ( CBM) ; 2♀♀, “ TIMOR LESTE Ramelau 8°54'45"S 125°29'58"E stunted eucs/vaccinium/open grass 2450–2550m 28.v.2012 C.Reid TL2012/091/576” K402545, K402553 ( AMS) ; 1♀, “ TIMOR LESTE Hatubuilico Rd 11.5km W t’off h’way 8°53'12"S 125°32'49"E E urophylla / Vacc pasture/gully 2050m 28.v.2012 C.Reid TL2012/080/762” K402554 ( AMS) .

Etymology. The name refers to the occurrence of this species on the island of Timor.

Diagnosis. Small, unicolourous dark species with short, oval-shaped elytra and wide, cordiform, slightly excised near the base, pronotum. Elytra with two, in some specimens unilaterally three, setiferous punctures. Aedeagus with compressed, remarkably securiform, apex. From M. reidi sp. nov. distinguished by fewer elytral setae and the shape of the apex of the aedeagus.

Description. Measurements. Length: 4.3–4.9 mm; width: 1.27–1.34 mm; ratios: width/length of pronotum: 1.18–1.23; width base/apex of pronotum: 0.96–1.02; width pronotum/ head: 1.36–1.45; length/width of elytra: 1.39–1.43; width elytra/pronotum: 1.53–1.58.

Colour ( Fig. 1 ). Unicolourous very dark piceous to black, the lateral margin of the elytra barely paler. Labrum and mandibles reddish-brown, palpi yellow, 1st–3rd antennomeres and legs pale red, rest of antenna darker, more or less dark piceous. Lower surface more or less piceous, elytral epipleurae pale reddish.

Head ( Fig. 1 ). Rather narrow in relation to prothorax. Eye moderately large, slightly convex, laterad little protruded, orbit fairly large, oblique-convex, c. 1/3 of length of eye. Frontal furrows deep, elongate, oblique, attaining about the middle of the eye, laterally bordered by a narrow ridge. Parafrontal sulcus almost encircling the eye. Frons convex, usually without a median pit. Clypeal suture well impressed. Labrum transverse, truncate, 6-setose. Mandibles moderately elongate, apically suddenly curved. Mentum with distinct, apically rounded tooth. Submentum with very elongate setae. Posterior supraorbital seta situated about at posterior margin of eye bur slightly removed mediad. Antenna short, barely attaining the basal angle of the pronotum, median antennomeres little longer than wide. Surface impunctate, with faint, irregular transverse strioles, with very faint, superficial, about isodiametric microreticulation, glossY.

Pronotum ( Fig. 1 ). Moderately large, fairly wide but somewhat variable, considerably wider than long, disk fairly convex; lateral margin evenly convex, with a faint excision in front of the basal angle, greatest width slightly in front of middle. Base moderately wide, about as wide as the apex. Apex straight, apical angle slightly projected but rounded. Base slightly convex. Basal angle distinct, about rectangular but slightlY differentlY shaped. Marginal channel narrow, barely widened towards angle. Both apex and base not margined. Anterior transverse sulcus shallow, barely impressed, v-shaped, posterior transverse sulcus deep. Median line well impressed, anteriorly and posteriorly abbreviated. Basal groove short, irregularly circular, fairly deep. Basal area coarsely punctate-corrugate. Anterior marginal seta situated slightly in front of middle, in the marginal channel, posterior marginal seta situated at basal angle. Surface impunctate, on disk with only traces of extremelY superficial, slightlY transverse microreticulation, lateral parts and basal area more distinctly microreticulate, surface glossy.

Elytra ( Fig. 1 ). Moderately short and wide, dorsally convex, not widened apicad, widest diameter about at middle. Humerus obtusely rounded, lateral margin evenly convex. Basal margin distinct, oblique, slightly sinuate, connected to scutellary striole. Five or even six median striae well impressed and coarsely punctate, slightly abbreviated at base, lateral striae increasingly indistinct; three median striae almost attaining the apex, the external striae increasingly abbreviated in front of the apex. Four or even five median intervals in basal half distinctly convex. Scutellary striole short, deep, situated mediad of the outturned sutural stria. Marginal channel narrow. 3rd interval with two or unilaterally three setiferous punctures attached to the 3rd stria, the anterior puncture situated in basal third, the 2nd puncture at or slightly behind middle, the accidental 3rd puncture situated usually near the posterior third of the elytra. Punctures distinct, setae extremely short. Near apex with a single setiferous puncture at the end of the 3rd stria. Marginal punctures moderately conspicuous, 15–16 in a row that is slightly interrupted in middle, marginal setae elongate if not broken. Intervals impunctate, with faint, more or less superficial microreticulation consisting of verY transverse meshes. Surface fairly glossy, not iridescent. Metathoracic wings absent.

Lower surface. Largely impunctate. Metepisternum slightly longer than wide. Sternum VII in male bisetose, in female quadrisetose.

Legs. Without striking features. Three basal tarsomeres of male anterior tarsus expanded and biseriately squamose.

Male genitalia ( Fig. 11 ). Genital ring comparatively narrow and elongate, asymmetric, with narrow base and wide, oblique apex. Aedeagus narrow and elongate, slightly sinuate, lower surface evenly concave. Apex rather compressed, strongly sclerotized, on the upper surface remarkablY hooked, and at apical end of orificium on the upper right surface with a small denticle. Orificium situated on the right surface. Internal sac with several sclerotized folds. Left paramere large, wide in basal half, with narrow, elongate, down-curved apex, bisetose at apex and without setae at lower margin. Right paramere narrower, but in basal half wide, likewise with elongate, curved apical part, bisetose at apex and with about 7–8 elongate setae in apical two thirds at lower margin.

Female gonocoxites ( Fig. 18 ). Gonocoxite 1 compact, apical rim with two delicate but rather elongate setae in the lateral part. Gonocoxite 2 rather short, dentiform, slightly curved, with two very stout ventro-lateral ensiform setae; apparently without a narrow dorso-median ensiform seta. Apex with an elongate, subapical nematiform seta that originates from a groove. Apical margin of the lateral plate rather densely setose.

Variation. Some variation is noted in size and relative width of the pronotum, also in distinctness of the lateral elytral striae, and in distinctness of the microreticulation on head, pronotum, and elytra.

Distribution. Western part of Timor Leste, in a restricted montane area, on the highest mountain in Timor (Ramelau) and associated ridges.

Collecting circumstances. Collected on the ground in open eucalypt woodland with grass and Vaccinium , between 1850 and 2750 m altitude.

Figures

Figure 1.Mecyclothorax timorensis sp. nov.(body length 4.5 mm).

Figure11.Mecyclothoraxtimorensissp.nov.male genitalia:aedeagus right side and lower surface,parameres, genital ring.Scales 0.5mm.

Figures 18–22. Female gonocoxites 1 and 2. (18) Mecyclothorax timorensis sp. nov. (scale 0.1 mm). (19) Rhytisternus externus sp. nov. (scale 0.5 mm). (20) Arhytinus timorensis sp. nov. (scale 0.25 mm). (21) Notagonum reidi sp. nov. (scale 0.25 mm). (22) Aristolebia timorensis sp. nov. (scale 0.5 mm).