Monolepta tiomanensis Mohamedsaid, 1999

Figs 38–40

Monolepta tiomanensis Mohamedsaid, 1999: 247 .

Type material. Holotype: “ Pahang, Pulau Tioman, 6-9 Jun 1990, Zaidi, Ismail, Ruslan / Holotype Monolepta tiomanensis n. sp. Mohammedsaid 1997” (UKM; Fig. 38). – Paratypes. 2 ex., same data as holotype (UKM). Type locality: 2º47′ N / 104º10′ E.

Further material examined. – Brunei. 1 ex., Temburong District, ridge NE of Kuala Belalong, 4º37′ N / 115º8′ E, 300 m, X.1992 (BMNH) . – Indonesia. 1 ex., Sibolangit, Sumatra, 3º18′ N / 98º34′ E, Mjöberg (NHRS) ; 1 ex., Java, Gg. Moeria, Tjolo 700–1000 m, 7º36′ S / 110º42′ E, 28.XII.1973, P. H. v. Doesburg Collectie Van Doesburg (RMNH); 1 ex., Sumatra Utara, Pasar Baru, 0º35′ S / 101º20′ E, 26.III.1996, K. Maruyama (CTJ) . – Malaysia. 1 ex., South China Sea, Pulau Tioman, Sedagang at light, 2º47′ N / 104º10′ E, V.1927, N. S.M. R.H (BMNH); 2 ex., Perlis, Kaki Bukit, Wang Kelian, 6º40′ N/100º′ E, 7.XII.1992, 19.VII.1994, Zabidi et al. (UKM) ; 3 ex., Pahang, Pulau Tioman, 2º47′ N/104º′ E, 22.–28.IV.1993, Zaidi et al. (UKM) ; 1 ex., N. Sembilan, Serting Ulu, 2º59′ N/102ºE, 30.III.1995, Ismail & Ruslan (UKM); 3 ex., N. Sembilan, Rembau, Gunong Datok, 2º34′ N / 102º3′ E, 30.VIII.1995, Ismail & Sham (UKM) ; 1 ex., Sarawak, Mt. Dulit, 4000 ft., 3º20′ N / 114º9′ E, 21.X.1932, Moss Forest (BMNH) ; 2 ex., Perak, F. M. S. Batang, Padang Jor Camp, 4º48′ N / 100º48′ E, 11.III.1924/1925, H. M. Pendlebury (BMNH) . – Singapore. 2 ex., Singapore, 1º21′ N / 103º49′ E, H. N. Ridley, 1904/3 (BMNH) .

Redescription

Total length. 4.75–6.15 mm (mean 5.56 mm; n = 10).

Head. Nearly impunctate, entirely black with very large eyes. Antenna slender, long, extending towards the apical third of elytra, first antennomeres brownish to black at base, second to terminal antennomere yellow (Fig. 39A). Third antennomere slightly longer than second; ratio length of second to third antennomere 0.75– 1.00 (mean 0.88); ratio length of third to fourth antennomere 0.27–0.45 (mean 0.36; Fig. 39B).

Thorax. Pronotum entirely pale yellow, transversely convex, anterior side broadened. Pronotal width 1.40– 1.80 mm (mean 1.64 mm), very broad, ratio length to width 0.57–0.61 (mean 0.59). Scutellum, meso- and metathorax yellow. Elytra punctuated like pronotum, yellowish and elongated. Elytral length 3.60–4.50 mm (mean 4.14 mm), maximal width of both elytra together 2.50–3.20 mm (mean 2.83 mm), ratio of maximal width of both elytra together to length of elytron 0.66–0.70 (mean 0.68; Fig. 38). Legs entirely yellowish.

Abdomen. Yellow.

Male genitalia. Median lobe short, broad, parallel-sided and rounded at apex. Tectum broad and nearly reaching the apex of median lobe. Median spiculae are strong, long, and horn-shaped, ventral spiculae comb-like, and lateral spiculae spur-like, close to the apex of median lobe (Fig. 39C).

Female genitalia. Spermatheca with large spherical nodulus, cornu long and curved (Fig. 39D). Two pairs of bursa sclerites of similar size, both carrying strong spines (Fig. 39E).

Diagnosis. Monolepta tiomanensis can be distinguished by the entirely yellowish abdomen and thorax to the contrasting black head. Entirely yellow dorsum is found also in M. jacobyi, where head is not black, but the narrow base of elytra. This species is also less slender and has a less broad pronotum than M. tiomanensis (Figs17A, 39A). There are several other species described in Monolepta with throughout yellow colouration and large eyes in the Oriental Region. This pattern is usually correlated with nocturnal activity. But all other species with this general pattern belong not to “true” Monolepta; a genital check is senseful in all doubtful cases.

Distribution. Known from Borneo (Malaysia, Brunei) Singapore, Sumatra and Java (Fig. 40).