Monolepta gracilipes Chûjô, 1938 reinstated

Luperodes pallidulus Chûjô, 1935: 162 .

Monolepta pallidula Chûjô, 1938: 144; Chûjô, 1962: 123; Chûjô, 1963a: 25; Chûjô, 1963b: 393; Chûjô, 1965: 97; Kimoto, 1965: 488; Kimoto, 1966: 32; Kimoto, 1969: 47; Kimoto, 1986: 58; Kimoto, 1987: 189; Kimoto, 1989: 256; Kimoto, 1991: 14; Takizawa et al., 1995: 11.

Monolepta gracilipes Chûjô, 1938: 145; Chûjô, 1962: 132; Chûjô, 1965: 97; Kimoto, 1969: 47 (synonymized with M. pallidula); Kimoto, 1986: 58.

Description. Total length: males: 5.1–6.4 mm (O: 5.63 mm; n= 6); females: 4.9–6.2 mm (O: 5.73 mm; n= 6). General color yellowish-brown (Fig. 1); in some specimens antenna, apex of tibia, and tarsi dark brown. Antennomeres 4–10 about 6.2 times longer than broad at apex (Fig. 13); length of second to third antennomere 0.79–1.00 (O: 0.87); length of third to fourth antennomere 0.36–0.50 (O: 0.59) (Fig. 12). Pronotal length to width 0.65–0.73 (O: 0.69). Maximal width of elytra to length of elytra 0.64–0.69 (O: 0.66). Length of basi-metatarsus to metatibia 0.50–0.57 (O: 0.55).

Male genitalia (Fig. 11). Median lobe broad, sub-parallel, curved apically; apex emarginated. Tectum wide and short, about 0.5x as long as median lobe. Ventral surface well sclerotized, with a ridge from apex to apical 1/7. Endophallus with apical spiculae horn-like; with very long median spiculae; four pairs of long, curved, lateral spiculae, apex acute; ventral spiculae consisting of a pair of long spiculae, longitudinal row of short rounded sclerites, and cluster of slender, curved spiculae at middle.

Female genitalia (Figs. 14–16). Spermathecal cornu (Fig. 14) slender, apically coiled; middle part long, apically and strongly curved, slightly widened near cornu; nodulus spherical, large; proximal spermathecal duct long, largest near nodulus, tightly coiled. Dorsal part of bursa-sclerites (Fig. 15) with teeth at outer margin of apical 1/3, extending into middle of dorsal surface, basally widened; ventral part (Fig. 16) slender, with teeth at inner margin.

Color variation. Some individuals have a black-margined elytra and a black metasternum and metepisternum (Fig. 2).

Type materials examined. The lectotype 3 of Monolepta gracilipes Chûjô, here designated to preserve stability and to make more universal use of this name, is labeled: “ Formosa. Musha (= Wushe, Nantou), 1919. V.18 – VI.15, T. Okuni / CoType / Monolepta gracilipes CHÛJÔ DET. M. Chujo / 1475” (TARI); paralectotypes: 33 (1472, 1474, 1480), 2ƤƤ (1473, 1488), with same data as lectotype (TARI), one paralectotype with same data deposited at the DEI; 13 (1471), 1Ƥ (2582): “ Formosa Arisan (= Alishan, Chiai), 1918. X.2 – 23, J. Sonan (TARI); 13 (1481): “Ritozan (= Litungshan, Taoyuan), 31.VII.1928, S. Issiki, 13 (1353), 1Ƥ (1354): “ INOUE (= Chingchuan, Hsinchu), FORMOSA, 21.VII.1935 COL. M. Chujo” (TARI); 1Ƥ (2583): “ Formosa, Shinchiku (= Hsinchu), 1918. VII.1–30, J. Sonan” (TARI); 1Ƥ (1476): “Taiheizan (= Taipingshan, Ilan), 25.VIII.1923, Col. T. Shiraki” (TARI); 1Ƥ (1489): “Kobayashi (= Hiaolin, Kaohsiung), 25.VII.1929, Formosa, Y. Miwa” (TARI); 13 (1478): “Shikiku (= Sunchitsun, Ilan), 3.XI.2928, Col. J. Sonan” (TARI); 1Ƥ (1479): “Nokosan (= Nengkaoshan, Nantou), 11.V.1919, Okuni, Sonan” (TARI); 1Ƥ (2584): “Nishimura (= Hsitsun, Miaoli), 24.VII.1929, Formosa, Y. Miwa” (TARI); 1Ƥ (1477): “Nankotaizan (= Nanhutashan, Taichung), 31-X-1928, Col. J. Sonan” (TARI).

Specimens examined. 53, 5ƤƤ (#6095-6104), Taipei, Lengshuikeng, 22.VI.2008, leg. S.-F. Yu; 1 Ƥ (#6436), Taipei, Sanchih, 30.VI.2008, W.-T. Liu; 1Ƥ (#432), Taipei, Tienmu, 08.XII.2006, leg. S.-F. Yu; 1Ƥ (#2322), Taoyuan, Tungyanshan, 08.VII.2007, leg. S.-F. Yu; 1Ƥ (#6945), Taoyuan, Tamanshan, 03.VIII.2008, leg. M.-H. Tsao; 13 (#6142), Hsinchu, Lupi, 24.VI.2008, leg. H. Lee; 23 (#6733-6734), 2ƤƤ (#6732, 6736), same locality, 19.VII.2008, leg. M.-H. Tsao; 23, 1Ƥ, (#6737-6739), same data but with 20.VII.2008; 4ƤƤ (#6814-6815, 6817-6818), same data but with 26.VII.2008; 1Ƥ (#2759), Pingtung, Tahanshan, 18.VII.2007, leg. M.-H. Tsao; 13, same locality, 20.VII.2007, leg. C.-F. Lee; 33, 7ƤƤ, Taitung, Tajen, 17.IX.2008, leg. W.-C. Wang; 1Ƥ (#4508), Taitung, Taimali, 20.III.2008, leg. P.-F. Wang. (all in TARI)

Notes. The Taiwanese population was recorded firstly as Luperodes pallidulus Baly, 1874 by Chûjô (1935). It was transferred to the genus Monolepta Chevrolat by Chûjô (1938). At the meantime, he described those specimens with black-margined elytra as a new species: M. gracilipes Chûjô, 1938 . Kimoto (1969) regarded these as a color variation of M. pallidula . Actually, the Taiwanese population is a distinct species with color variation which is different from the uniform M. pallidula (see below). Since M. gracilipes is an available name, it should be reinstated.

Diagnosis. This species is close to Monolepta pallidula with the yellowish-brown body and similar endophallus, but differing by the wide and truncate apex of median lobe, relatively wider dorso-ventrally median lobe (Fig. 17), the narrowed anterior area of middle part of spermatheca (Fig. 19), the more prominent-toothed and narrow-based dorsal bursa sclerites (Fig. 20), and the ventral bursa sclerites with more and fine teeth. (Fig. 18). In addition, Monolepta gracilipes displays color variation on the elytra and metasternum in contrast with no color variation in M. pallidula .

Distribution. Taiwan. This species seems to be the most common species of Monolepta in Taiwan based on lots of records and field experiences of the senior author.