Stilbocistela malaica, Novák, 2009

Novák, Vladimír, 2009, A review of the genus Stilbocistela (Coleoptera: Tenebrionidae: Alleculinae) with description of new species from Malaysia and Indonesia, Acta Entomologica Musei Nationalis Pragae 49 (2), pp. 783-794 : 789-791

Stilbocistela malaica sp. nov.

( Figs. 9–13 )

Type locality. Malaysia, Cameron Highlands, Tanah Rata, 1200–1500 m a.s.l.

Type material. HOLOTYPE: J, ‘ MALAYSIA West, PAHANG, / Cameron Highlands , / TANAH RATA, 1200-1500 m, 3.-19.ii.2005, / P. Čechovský lgt.’ ( NMPC) . PARATYPES: 14 specimens, same data as holotype (NMPC, VNPC) ; 1 specimen, ‘ MALAYSIA-W, Pahang, / 30 km SE of IPOH, 1500 m, / Banjaran Titi Wangsa , / TANAH RATA, 14 .-

15.iii. / 2002, P. Čechovský leg.’ ( VNPC); 3 specimens, ‘MALAYSIA-W, Pahang, / 30 km E of IPOH, 1500 m, / Cameron Highlands ,/ TANAH RATA, 22.-26.i./ 1999, P.Čechovský leg.’ ( VNPC) ; 2 specimens,‘ MALAYSIA West, PERAK, / 40 km SE of IPOH, 900 m, / Banjaran Titi Wangsu , / RINGLET, 29.iii.-15.iv.2004, / P. Čechovský lgt.’ ( VNPC) ; 26 specimens, ‘ Malaysia NW / Cameron Highlands / Tanah Rata / 16.-29.i.2006 / P. Viktora lgt.’ ( PVKC, VNPC) ; 2 specimens, ‘ Malaysia NW / Cameron Highlands / Tanah Rata, Mt. Gunung Jasar / 26.iv.-15.v.2006 / P.Viktora lgt.’ ( PVKC, VNPC) ; 25 specimens, ‘W Malaysia / Cameron Highlands / Tanah Rata, Mt. Gunung Jasar / 30.i.-24.ii.2008 / P. Viktora lgt.’ ( PVKC, VNPC) ; 3 specimens, ‘ MALAYSIA, Pahang, / Cameron Highlands, / Tanah Rata, edge of / degraded rainforest, // at light, No. 72, / 21.III.-2.IV.1995 / O. Merkl’ ( HNHM, VNPC) ; 1 specimen, ‘ MALAYSIA, Pahang, / Cameron Highlands, / Parit Falls, / degraded rainforest, // at light, No. 90, / 27.III.1995, / O. Merkl’ ( HNHM) ; 1 specimen, ‘ MALAYSIA, Pahang, / Cameron Highlands, / 2 km S Tanah Rata, / on Tapah Road // roadsite vegetation, / swept & Beaten , No. 89, / 27.III.1995, O. Merkl’ ( HNHM) ; 1 specimen, ‘ MALAYSIA, Pahang, / Fraser´s Hill, May- / bankL. Tr. , 7-27-1992, / C.W. & L.B. O´Brien’ ( HNHM) ; 1 specimen, ‘ MALAYSIA, Pahang, / Fraser´s Hill, May- / bankL. Tr. , 7-15-1992, / C.W.& L.B. O´Brien’ ( HNHM). The types are provided with a printed red label: ‘ Stilbocistela malaica sp. nov. HOLOTYPUS [or PARATYPUS] V. Novák det. 2008 ’.

Description. Habitus of male holotype as in Fig. 9 , body oval, strongly vaulted. General colouration from pale brown to dark brown. Length 4.93–6.19 mm, width at elytral midlength 2.22–2.90 mm.

Male (holotype). Head ( Fig. 10 ) brown in colour, large, shiny, anterior part with sparse, short, light setation and punctuation, punctures large, coarse, interspaces between punctures narrow with microgranulation. Posterior part glabrous with indistinct punctuation, punctures shallow and small. Eyes dark in colour, large, transverse, emarginate; distance between eyes approximately as long as diameter of eye and distinctly longer than antennomere 2, approximately as long as antennomeres 1 and 2 combined. Ocular index equal to 33.34. Head 1.10 mm wide, widest across eyes, approximately 0.53 times as wide as pronotal base; visible part of head 0.92 mm long.

Antenna ( Fig. 11 ) slightly rugose, relatively short, 2.28 mm long, i.e. reaching 0.42 of body length.Antennomeres 1–5 pale brown, anterior part of antennomere 5 narrowly dark, antennomeres 6–11 dark brown, anterior part of antennomere 11 pale brown. All antennomeres with dark setation, antennomeres 1–4 with sparse setation and slightly shiny, antennomeres 5–11 with dense setation and more dull.Antennomere 2 shortest, antennomeres 4–10 conspicuously widened at apex, distinctly serrate. Antennomere 3 slightly shorter than each of antennomeres 4–11. Ratios of relative lengths of antennomeres 1–11 equal to 0.72: 0.44: 1.00: 1.03: 0.99: 0.95: 1.02: 1.10: 1.00: 0.99: 1.11. Length / maximum width ratios of antennomeres 1–11 equal to 1.63: 1.29: 2.53: 2.29: 1.96: 1.76: 1.98: 1.92: 1.96: 1.67: 2.02.

Maxillary palpus pale brown, concolorous with apical part of head and antennomeres 1–4, with short light setation and microgranulation, dull. Second and penultimate maxillary palpomere distinctly broadest at apex, penultimate palpomere shortest, ultimate palpomere longest and broadly triangular. Ratios of relative lengths of palpomeres 2–4 equal to 1.39: 1.00: 1.67. Length / maximum width ratios of palpomeres 2–4 equal to 3.56: 1.86: 1.17.

Pronotum ( Fig. 10 ) brown, strongly shiny, glabrous, strongly transverse, longest in middle (length 1.02 mm) and widest at base (width 2.06 mm); pronotal index equal to 49.48. Border almost complete, only in middle of anterior margin and in one third of posterior margin near posterior angles indistinct; posterior margin bisinuate. Posterior angles roundly obtuse-angled, lateral margins slightly rounded anteriorly. Anterior angles conspicuous, obtuse-angled. Surface sparsely and shallowly punctate, punctures small, interspaces very broad, rugose with glabrous and shiny parts.

Elytra unicolorous, brown, strongly oval, glabrous, strongly shiny, 3.48 mm long and 2.62 mm wide, slightly broader than pronotum, widest near midlength; elytral length / maximum width ratio equal to 1.34. Strial punctures conspicuous, separated by less than one diameter. Elytral intervals with very small punctures and microgranulation, strongly shiny. Epipleura well developed, brown, evenly narrowing in basal half, in apical half from abdominal ventrite 2 to ventrite 5 parallel, then narrowing to rounded apex.

Scutellum triangular, glabrous, brown, concolorous with elytra, sides narrowly dark.

Legs unicolorous, pale brown, tarsi with dense light setation, tibiae with short and sparse light setation. Femora thicker than tibiae, without distinct setation. Tibiae very narrow, slightly dilated at apex. Tarsomeres of all tarsi narrow, only anterior and middle tarsomeres 3 and 4 and posterior tarsomere 3 slightly broadened and lobed. Ratios of relative lengths of tarsomeres 1–5 and 1–4 equal to 1.00: 0.51: 0.45: 1.01: 1.75 (protarsus), 1.00: 0.38: 0.47: 0.41: 0.85 (mesotarsus), and 1.00: 0.27: 0.26: 0.63 (metatarsus). Both anterior tarsal claws with 4 teeth.

Ventral side of body pale brown, concolorous with dorsal side.Abdominal ventrites without setation, glabrous, with microgranulation, slightly shiny. Sides of abdominal ventrites with fine longitudinal rugosities, ultimate and penultimate ventrites darker than ventrites 1–3.

Aedeagus ( Figs. 12–13 ) pale yellowish brown, slightly shiny. Basal piece 4.69 times as long as apical piece, rounded at basal half, then with lateral sides straight in apical half. Basal half of basal piece more than twice as wide as its apex in dorsal view. Apical piece almost straight, very finely narrowing to rounded apex in dorsal view, apex slightly beak-shaped in lateral view.

Female. Habitus similar to male. Length 6.12 mm; length of head 0.90 mm; width of head 1.16 mm. Ocular index 30.21. Pronotal length (along midline) 1.09; pronotal width at base 2.25 mm. Pronotal index 48.53. Elytral length 4.13 mm; elytral width 2.82 mm.

Ratios of relative lengths of antennomeres 1–11 equal to 0.77: 0.46: 1.00: 1.02: 1.00: 0.96: 1.01: 1.01: 0.99: 1.01: 1.14. Length / maximum width ratios of antennomeres 1–11 equal to 2.17: 1.41: 2.67: 2.11: 1.80: 1.58: 1.67: 1.59: 1.51: 1.49: 1.71.

Ratios of relative lengths of tarsomeres 1–5 and 1–4 equal to 1.00: 0.41: 0.53: 0.60: 0.56 (protarsus), 1.00: 0.44: 0.50: 0.59: 1.06 (mesotarsus), and 1.00: 0.37: 0.32: 0.61 (metatarsus).

Variability. The type specimens (n = 81) vary somewhat in size (each character is given as its mean value, with full range in parentheses): body length 5.43 mm (4.93–6.19 mm); head length 0.85 mm (0.73–1.06 mm); head width 1.03 mm (0.93–1.18 mm); ocular index 32.60 (28.07–36.48). Pronotal length (along midline) 0.95 mm (0.87–1.07 mm); pronotal width at base 1.96 mm (1.75–2.28 mm); pronotal index 48.27 (46.03–50.52). Elytral length 3.63 mm (3.30–4.21 mm); elytral width 2.33 mm (2.22–2.90 mm).

Differential diagnosis. Stilbocistela malaica sp. nov. differs from other species mainly by having antennomere 3 almost as long as each of antennomeres 4–10 (antennomere 3 distinctly shorter in the remaining species). For further details see the key above.

Etymology. This species is named after the distribution.

Distribution. Peninsular Malaysia.

Figures

Figs.9–18. 9–13 – Stilbocistela malaica sp. nov. (male holotype): 9 – habitus; 10 – head and pronotum; 11 – antenna; 12 – aedeagus, lateral view; 13 – aedeagus, dorsal view. 14–18 – Stilbocistela manoiensis Borchmann, 1933 (male): 14 – habitus; 15 – head and pronotum; 16 – antenna; 17 – aedeagus, lateral view; 18 – aedeagus, dorsal view.