Alyculus malaypeninsularis, Takahashi, Naoki, Bocak, Ladislav & Abd, Idris, 2016

Takahashi, Naoki, Bocak, Ladislav & Abd, Idris, 2016, Discovery of a new species of the brachyelytrous net-winged beetle genus Alyculus (Coleoptera: Lycidae) from Peninsular Malaysia, Zootaxa 4144 (1), pp. 145-150 : 146-148

Alyculus malaypeninsularis sp. nov.

( Figs. 1–5 )

Type material. Holotype (deposited in UKMB), male, Malaysia, Pahang, Cameron Highlands, Gunung Brinchang , 13.iii.2005, N. Takahashi leg. Paratypes, 1 male ( ELKU), same locality and collector as holotype, 13.vii.2003 ; 1 male (LMBC), 11.iii.2005. 1 male ( ELKU), Malaysia, Pahang, Cameron Highlands, Gunung Berembun , 19.i.2006, N. Takahashi leg . 1 male ( UKMB), Malaysia, Pahang, Genting Highland , 12.i.2006, N. Takahashi leg . 1 male ( UKMB), Malaysia, Pahang, Bukit Fraser, Abu Suradi Trail—Mager Trail , 15.iii.2005, N. Takahashi leg.

Diagnosis. Body dark brown. Antennomere 3 slightly compressed and 1.75–2.30 times longer than wide. Pronotum without longitudinal carina on surface. Parameres of aedeagus widest at about basal 3/8 of length and hooked at apices.

Description. MALE. Body tiny and elongate ( Fig. 1 ), almost uniform dark brown and covered with brownish pubescence; cranium slightly dark reddish and sometimes faintly lighter around prominent frontal part ( Fig. 2 ); eyes black; pronotum and prosternum feebly dark reddish in some cases; antennomere 2 yellowish ( Figs 2–3 ); pterothoracic ventrites and pleura sometimes faintly lighter; hindwings slightly dusky ( Fig. 1 ); apical portions of tarsomere 5 with claws of legs more or less yellowish.

Head ( Fig. 2 ) small, hypognathous, quadrately rounded and widest at eyes in dorsal view; cranium with prominent frontal part, gently convex dorsad though depressed just behind prominent frontal part and slightly flattened behind vertex, lustrous without apparent microstructure and sparsely covered with long pubescence. Eyes with granular facets, large, semiglobularly prominent, shallowly and obtusely emarginate at posterior margin in profile, and diameter of an eye in profile 0.87–1.18 times as large as interocular distance. Antennae ( Figs 1–3 ) inserted anterolaterally on prominent frontal part, moderately robust, densely covered with pubescence though less so on antennomeres 1–2, extending over elytral apices by antennomeres 10–11, scapus more or less robust, subcylindrical but weakly constricted on laterodistal surface at near the base, pedicel small and slightly broad, antennomeres 3–5 slightly compressed dorsoventrad, antennomere 3 subparallel at sides, but weakly constricted at base and 1.75–2.30 times longer than wide, subsequent antennomeres becoming gradually more subcylindrical and less compressed, antennomere 11 longest. Mouthparts with reduced mandibles, labrum minute, maxillary palpi 4- segmented with lanceolate terminal palpomeres prolonged at apices and more than 1.50 times longer than palpomere 3.

Pronotum subtrapezoidal ( Figs 1–2 ), broader posteriad, strongly transverse, 1.7 5–1.88 times as wide as long at posterior margin; disc without longitudinal carina, sparsely provided with long erect pubescence, irregularly punctate particularly so on the areas along anterior and posterior margins and midline, finely granulate in basal third, gently convex medio-dorsad, transversely and feebly depressed at basal third, almost straight and feebly marginate at anterior margin, obtuse with blunt tips at front angles, somewhat emarginate mesad in dorsal view at lateral margins, which are weakly carinated in profile due to the continuity of pronotum and epipleura, acutely and apparently prominent laterad at hind angles, gently bisinuate and feebly marginate though sometimes faintly emarginate in the middle of posterior margin. Prothoracic epipleura irregularly punctate on surfaces. Scutellum bifurcate at apex, each distal process slender, protruded lateroposteriad and gently curved laterad.

Elytra abbreviated ( Fig. 1 ), 1.7–2.0 times as long as wide at humeri, covering two basal abdominal segments, slightly dehiscent in posterior half of sutural line, each gradually narrowed posteriad and rounded at apex; their surface without costae or reticulate cells, rugose, densely covered with minute papillae bearing setae. Hind wings extending beyond elytral apices ( Fig. 1 ).

Legs slender; femora and tibiae slightly flattened; tibia 1.15–1.30 times as long as femur and tarsomere V 1.33–1.76 times as long as tarsomere IV in fore leg; tarsomeres 2–4 usually faintly shorter than the preceding one, and tarsomere 5 approximately as long as tarsomere 1 in hind leg; claws simple.

Meso- and metaventrites lustrous, and densely covered with pubescence on their surfaces compared to pubescence of cranium; discrimen traced in posterior half, but sometimes reaching anterior third to anterior margin of metaventrite. Abdomen elongate; venter lustrous though somewhat rugulose, densely covered with darker pubescence; penultimate sternite slightly narrower than the preceding one; ultimate tergite slightly elongate, semicylindrical, narrowed apicad; ultimate sternite leaf-shaped and narrowed basad.

Aedeagus ( Fig. 4 ) trilobate; phallus slender, tapering to apex, slightly shorter than parameres; parameres widest at about basal 3/8 of length and tapering apicad in distal halves, flattened in profile and subparallel in distal third, weakly hooked at apices.

FEMALE unknown.

Measurements. Body length 2.11–2.70 mm, pronotal length 0.20–0.30 mm, pronotal width 0.38–0.55 mm, length of elytra 0.75–1.0 mm, humeral width 0.44–0.53 mm, frontal interocular distance 0.11–0.17 mm, eye diameter in lateral view 0.13–0.16 mm.

Distribution. West Malaysia (Pahang).

Remarks. This new species has the largest in body size in the genus. It resembles A. wittmeri from northern Sumatra in having the parameres of aedeagus with the hooked apices, but the body is much larger and dark brownish in coloration unlike the testaceous color of A. wittmeri . The pronotum is narrower, and the parameres of aedeagus are widest at the basal 3/8.

Etymology. The specific epithet is derived from the known distribution of the species.

Figures

FIGURE 4. Aedeagus of Alyculus malaypeninsularis sp. nov., dorsal view. Scale: 0.1 mm.

FIGURES 1 – 3. Alyculus malaypeninsularis sp. nov. 1, habitus, dorsal view; 2, head and pronotum, dorsal view; 3, basal antennomeres. Scales: 0.5 mm (Fig. 1); 0.1 mm (Figs 2 – 3).

FIGURES 5 – 6. Alyculus malaypeninsularis sp. nov. 5, habitus on a sweeping net in the field; 6, habitat of A. malaypeninsularis sp. nov. in the Genting Highland, Pahang, Malaysia.