Trurlia biarcuata, 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 : 71-74

Trurlia biarcuata , new species

( Figs. 1b , 2b , 3c, d )

Material examined. – Holotype. Male, two labels: “ SUMATRA: W Sum. #19 \ Anai V. Nat. Res. \ 10 km W Padangpanjan \ 200 m, 17, XI.1989, Löbl \ Agosti, Burckhardt” [white, printed], “ TRURLIA \ biarcuata m. \ P. JAŁOSZY SKI, ‘2010 \ HOLOTYPUS ” [red,

printed] ( MHNG). Paratypes: 2 females , same data as holotype, except one specimen from altitude of 250 m ( MHNG, PCPJ) .

Diagnosis. – Anterior part of frons and clypeus with fine transverse wrinkles; basic vestiture of pronotal disc not visible under magnification 40×; front angles of pronotum in strictly dorsal view barely visible, not projecting; pronotum in posterior half slightly but distinctly narrowing toward base; ante-basal pronotal groove distinctly biarcuate; humeral carinae slightly longer than half length of elytra; aedeagus in ventral view with subrectangular apex and parameres with simple (i.e., not narrowed) apices, each bearing three long setae.

Male. – Body ( Figs. 1b , 2b ) strongly convex, oval, with distinct but shallow constriction between pronotum and elytra; pigmentation chestnut-brown with slightly lighter antennae, palps and legs, vestiture light brown. Body length 1.15 mm.

Head moderately large in relation to pronotum, length 0.13 mm, width 0.30 mm, vertex and frons confluent and convex, evenly and densely covered with large, elongate, sharply marked and deep punctures separated by spaces half as long as puncture diameters, clypeus with very fine transverse wrinkles; supraantennal tubercles small and weakly raised; eyes large and strongly convex, coarsely faceted; antennal club large and oval, length of antennae 0.39 mm.

Pronotum broadest between middle and anterior third, weakly narrowing toward base, in strictly dorsal view trapezoidal with front angles weakly protruding anterad and barely visible; length 0.35 mm, width 0.55 mm; lateral margins microserrate, in anterior half rounded, in posterior half nearly straight; hind angles slightly obtuse and blunt; posterior margin with three shallow emarginations; internal ante-basal foveae small but distinct, connected by sharply marked, biarcuate groove; oval lateromedian foveae located in middle, each with frontomesal fringe of long setae. Surface of disc densely and unevenly covered with large, mostly nearly circular or slightly elongate, sharply marked and deep punctures separated by spaces 0.5-1.5× as long as puncture diameters; basic setae extremely short, sparse and recumbent, visible under magnifications ≥ 80×, additionally pronotum with several pairs of very long, strongly curved and suberect macrosetae ( Fig. 2b ).

Elytra oval and very short, broadest distinctly anterior to middle, length 0.68 mm, width 0.65 mm, elytral index 1.04; humeral carinae nearly parallel to each other, as long as 0.56× of elytral width; surface of elytra covered with punctures much smaller, shallower and sparser than those on pronotum, separated by spaces 1.5–2× as long as puncture diameters; each elytron with ca. 20 long, strongly curved and suberect macrosetae ( Fig. 2b ). Hind wings not studied.

Aedeagus ( Figs. 3c, d ) 0.33 mm in length, in ventral view distinctly narrowing toward separated, subrectangular apex; internal armature simple and lightly sclerotized, composed of median tubular structure in apical half of aedeagus; parameres not reaching apex of median lobe, with simple apices, each bearing three equally long setae: apical and median subapical setae inserted very close to each other, proximal subapical seta remarkably distant from apex.

Female. – Externally indistinguishable from male, only slightly larger; body length 1.18–1.19 mm; length of head 0.13–0.15 mm, width 0.30 mm; length of antennae 0.38–0.39 mm; length of pronotum 0.38–0.40 mm, width 0.55–0.58 mm; length of elytra 0.65–0.66 mm, width 0.63–0.64 mm, elytral index 1.04.

Etymology. – The Latin adjective biarcuatus refers to the shape of the ante-basal pronotal groove in this species.

Distribution. – Sumatra ( Indonesia: province West Sumatra).

Remarks. – Trurlia biarcuata has a relatively unremarkable external morphology and identifications must be confirmed by examination of the unique aedeagus.

Trurlia constricta , new species

( Figs. 1c , 2c , 4a, b )

Material examined. – Holotype. Male, two labels: “ SABAH: Poring Hot \ Springs, 500 m \ 6. V.1987 \ Burckhardt - Löbl” [white, printed], “ TRURLIA \ constricta m. \ P. JAŁOSZY SKI, ‘2010 \ HOLOTYPUS ” [red, printed] ( MHNG). Paratypes: 5 females, same data as holotype ( MHNG, PCPJ).

Diagnosis. – Anterior part of frons and clypeus with sparse punctures, without wrinkles; basic vestiture of pronotal disc barely noticeable under magnification 40×; front angles of pronotum in both sexes weakly projecting anterad, barely visible in strictly dorsal view; pronotum in posterior half strongly narrowing toward base; humeral carinae longer than half length of elytra; aedeagus in ventral view slightly constricted laterally in subapical region, with oval, rounded apex, and apex of each paramere rapidly narrowed at median subapical seta.

Male. – Body ( Figs. 1c , 2c ) strongly convex, oval, with deep constriction between pronotum and elytra; pigmentation moderately dark brown with slightly lighter antennae, palps and legs, vestiture light brown. Body length 1.18 mm.

Head moderately large in relation to pronotum, length 0.15 mm, width 0.30 mm, vertex convex, evenly and densely

covered with large, sharply marked and deep punctures

separated by spaces comparable to puncture diameters; frons slightly impressed, with punctures slightly smaller than those on vertex but equally distinct and dense; supraantennal tubercles small but very distinct; eyes large and strongly convex, coarsely faceted; antennal club large and oval, length of antennae 0.38 mm.

Pronotum broadest near middle, strongly narrowing toward base, in strictly dorsal view nearly semicircular with barely visible front angles; length 0.38 mm, width 0.55 mm; lateral margins microserrate, strongly rounded in anterior half and weakly but distinctly rounded in posterior half; hind angles slightly obtuse and blunt; posterior margin shallowly biemarginate with barely marked and very short median emargination; internal ante-basal foveae small but distinct, connected by sharply marked, arcuate groove; oval lateromedian foveae located distinctly posterior to middle, each with frontomesal fringe of long setae. Surface of disc densely covered with moderately large, mostly circular or slightly elongate, sharply marked and deep punctures separated by spaces as long as 0.5-1 puncture diameter; basic setae very short, sparse and recumbent, discernible under magnification 40×, additionally pronotum with several pairs of very long, strongly curved and suberect macrosetae ( Fig. 2c ).

Elytra oval and very short, broadest between middle and anterior third, length 0.65 mm, width 0.63 mm, elytral index 1.04; humeral carinae feebly divergent caudad, as long as 0.6× elytral width; surface of elytra covered with punctures much smaller and much 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 macrosetae ( Fig. 2c ). Hind wings not studied.

Aedeagus ( Figs. 4a, b ) 0.25 mm in length, in ventral view moderately narrowing toward apex and slightly constricted in subapical region; apex separated, oval and rounded; internal armature very lightly sclerotized, barely discernible, containing median bell-shaped structure located near middle of aedeagus; parameres reaching apex of median lobe, with modified apices and three unequal setae: moderately long apical seta inserted on long and narrow “projection”; short median and very long proximal subapical setae approximate to each other and distant from apical seta.

Female. – Externally indistinguishable from male, on average slightly larger and stouter; body length 1.20–1.24 mm (mean 1.22 mm); length of head 0.15 mm, width 0.30–0.33 mm (mean 0.31 mm); length of antennae 0.35–0.40 mm (mean 0.38 mm); length of pronotum 0.40–0.41 mm (mean 0.41 mm), width 0.58–0.60 mm (mean 0.59 mm); length of elytra 0.65–0.68 mm (mean 0.66 mm), width 0.63–0.65 mm (mean 0.64 mm), elytral index 1.00–1.04.

Etymology. – The Latin adjective constrictus (fem. constricta ) refers to the distinct constriction between the pronotum and elytra in this species.

Distribution. – Borneo (Eastern Malaysia: Sabah).

Remarks. – This is another unremarkable species; certain identifications can be made only on the basis of the unique aedeagus. Females can be determined by direct comparison with males.

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. 3. Aedeagus in ventral (a, c) and lateral (b, d) views. Trurlia acutangula new species (a, b), Trurlia biarcuata new species (c, d). Scale bar = 0.1 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.