Trurlia semengohensis, ski, 2011

ski, P. Jałoszy, 2011, Four New Species Of Trurlia Jałoszy Ski From Sumatra And Borneo (Coleoptera: Staphylinidae: Scydmaeninae), Raffles Bulletin of Zoology 59 (1), pp. 69-75 : 74-75

Trurlia semengohensis , new species

( Figs.1d , 2d , 4c, d )

Material examined. – Holotype. Male , two labels: “ SARAWAK \ Semengoh For. \ 11miSW Kuching \ R.Taylor, 5.68” [white, printed], “ TRURLIA \ semengohensis m. \ P. JAŁOSZY SKI, ‘2010 \ HOLOTYPUS ” [red, printed] ( MHNG).

Diagnosis. – Anterior part of frons and clypeus with small punctures, without wrinkles; basic vestiture of pronotal disc extremely short, not visible under magnification 40×; front angles of pronotum in males distinctly projecting anterad; pronotum in posterior half not narrowing toward base; humeral carinae longer than half length of elytra; aedeagus in ventral view with abruptly tapered, trapezoidal apex, and apex of each paramere rapidly narrowed at median subapical seta.

Male. – Body ( Figs. 1d , 2d ) strongly convex, oval, with shallow constriction between pronotum and elytra; pigmentation moderately dark reddish-brown with slightly lighter antennae, palps and legs, vestiture light brown. Body length 1.10 mm.

Head moderately large in relation to pronotum, length 0.10 mm, width 0.30 mm, vertex convex, unevenly and densely covered with moderately large, slightly elongate, sharply marked and deep punctures separated by spaces 0.5-1.5× as long as puncture diameters; frons slightly flattened, with similar punctures as those on vertex; supraantennal tubercles small and weakly raised; eyes large and strongly convex, coarsely faceted; antennal club large and oval, length of antennae 0.43 mm.

Pronotum equally broad between hind angles and middle, in strictly dorsal view trapezoidal with front angles distinctly protruding anterad and their frontomesal surfaces slightly flattened and expanded; length 0.35 mm, width 0.51 mm; lateral margins microserrate, straight just behind front angles, rounded near middle and straight in posterior half; hind angles nearly right and blunt; posterior margin with three shallow emarginations; internal ante-basal foveae small but distinct, connected by sharply marked, arcuate groove; oval lateromedian foveae located just posterior to middle, each with frontomesal fringe of long setae. Surface of disc very densely covered with moderately large, slightly elongate, sharply marked and deep punctures separated by spaces approximately equal to half puncture diameter; basic setae extremely short, sparse and recumbent, barely noticeable under magnification 80×, additionally pronotum with several pairs of very long, strongly curved and suberect macrosetae ( Fig. 2d ).

Elytra oval and relatively elongate, broadest distinctly anterior to middle, length 0.65 mm, width 0.59 mm, elytral index 1.11; humeral carinae nearly parallel, as long as 0.58× of elytral width; surface of elytra covered with punctures much smaller, and shallower but only slightly sparser than those on pronotum, separated by spaces 1–1.5× as long as puncture diameters; each elytron with ca. 15 long, strongly curved and suberect setae ( Fig. 2d ). Hind wings not studied.

Aedeagus ( Figs. 4c, d ) 0.40 mm in length, in ventral view distinctly narrowing toward tapered, trapezoidal apex; internal armature relatively darkly sclerotized and complex, in lateral view showing very large and elongate conical structure occupying most of apical part of aedeagus; parameres not reaching apex of median lobe, with modified apices and three unequal setae: very long apical seta inserted on long and narrow “projection”, very short median and very long proximal subapical setae approximate to each other and distant from apical seta.

Female. – Unknown.

Etymology. – Named after the Semengoh Forest in Sarawak, Borneo.

Distribution. – Borneo (Eastern Malaysia: Sarawak).

Remarks. – In addition to the diagnostic characters listed above, Trurlia semengohensis is distinct and easily distinguishable from all congeners on the basis of its very small body reaching only 1.10 mm (all other species have 1.14–1.28 mm in length). Trurlia insana , though much larger (1.28 mm), is most similar to T. semengohensis in general body shape, which is more elongate than that of any other species described in this paper; the elytral indexes of these two species are 1.12 and 1.11, respectively, while the elytra of T. acutangula , T. biarcuata and T. constricta are very stout and their indexes range from 1.00 to 1.04.

Figures

Fig. 1. Dorsal habitus of holotype males. Trurlia acutangula new species (a), Trurlia biarcuata new species (b), Trurlia constricta new species (c), Trurlia semengohensis new species (d). Scale bars = 0.2 mm.

Fig. 2. Simplified outline of left body half in dorsal view and distribution of macrosetae. Trurlia acutangula new species (a), Trurlia biarcuata new species (b), Trurlia constricta new species (c), Trurlia semengohensis new species (d). Scale bars = 0.2 mm.

Fig. 4. Aedeagus in ventral (a, c) and lateral (b, d) views. Trurlia constricta new species (a, b), Trurlia semengohensis new species (c, d). Scale bar = 0.1 mm.