Monolepta rufofulva Chûjô 1938: 149; Chûjô 1962: 119; Chûjô 1963: 393; Kimoto 1969: 49; Wilcox 1973: 555 (catalogue); Kimoto 1989: 257; Kimoto 1991: 15; Takizawa et al. 1995: 11; Kimoto and Chu 1996: 81 (catalogue); Kimoto and Takizawa 1997: 386; Beenen 2010: 484 (catalogue).

Diagnosis. Monolepta rufofulva is most similar to Monolepta chinkinyui Kimoto, 1996 based on its evenly convex and rounded lateral margin of the pronotum, but it differs by the elongate and black elytra.

Redescription. Oval. Total length 3.1–3.4 mm. Greatest width across both elytra 1.9 mm. Macropterous. General color (Figs. 3–6) reddish brown, antenna black or blackish brown except basal 2–3 antennomeres and maxillary and labial palpi dark brown. Head: Maximal width of head across both eyes 0.3–0.4 mm.Vertex impunctate, shiny.Frontal tubercles indistinct. Antenna relatively long, length of body 1.2X longer than antenna; antennomeres IV–VIII widened in males (Fig. 21), about 3.0 times longer than broad at apex; antennomeres IV-VIII slender in females (Fig. 22), about 3.7 times longer than broad at apex; antennomeres IX-XI slender; length ratio of antennomeres II to III 1.53–1.85 in males (Fig. 27), 1.12–1.17 in females (Fig. 28); length ratio of antennomeres III to IV 0.21–0.25 in males (Fig. 27), 0.35–0.39 in females (Fig. 28). Labrum square with straight apical margin. Pronotum: Pronotal length to width ratio 0.50–0.55. Greatest width just before middle. Sides rounded. Front corners with calli, hind corners obtuse. Anterior border immarginate; lateral borders and posterior border with fine margin. Upper surface with fine punctures, shiny. Elytra: Base broader than pronotum; ovate with greatest width just behind middle; maximum ratio of elytral width to length 0.74. Humerus prominent; surface with shallow punctures and velvet sheen. Short, erect hairs sparsely distributed on apical fifth of elytral surface. Elytral epipleuron even, wide from base to middle of metasternum, then abruptly narrowing towards anterior margin of first abdominal ventrite, then gradually narrowing towards apex. Legs: Slender. Hind tibiae with large apical spine. Length ratio of basi-metatarsus to metatibia 0.54–0.62. Basi-metatarsus small, shorter than other tarsomeres combined. Tarsal claws appendiculate. Ventral surface: Procoxal cavities closed. Sexual dimorphism: Last abdominal sternite of male trilobed with central lobe almost square with straight margin (Fig. 4). Antenna in male (Figs. 3, 21) wider than in female (Figs. 5, 22). Male genitalia: Median lobe slender (Fig. 23), apically tapering, widest near base, apex rounded; ventral surface well-sclerotized; weakly curved in lateral view (Fig. 24). Tectum apically pointed and short, about 0.3X as long as median lobe. Endophallus in dorsal view (Fig. 29) with 1 pair of apical spicula visible, each with 4 teeth at apex; in ventral view, 2 pairs of spiculae (Fig. 31): 1 pair of bsal spiculae with basal tooth and pointed apex and 1 apical pair of spiculae pointed at both ends. In lateral view, basal sclerite slender and curved (Fig. 30). Female genitalia: Spermathecal cornu (Fig. 25) slender, apically strongly tapering, abruptly widened near nodulus; nodulus spherical, large; spermathecal duct extremely wide at base, short. Only 1 pair of bursa-sclerites (Fig. 26), composed of row of 3–4 teeth.

Type Series. The lectotype female of M. rufofulva, here designated to preserve stability and to make more universal use of this name, is labeled: “ KUARU (= Kenting Natural Park, Pingtung) FORMOSA 11. VI.1937 COL. M. CHUJO / COType (circular and white label, yellow letters) / Monolepta rufofulva CHÛJÔ DET. M. CHUJO / 1376” (TARI). Paralectotypes: 1♀: “ Formosa Hoshun (Henchun, Pingtung), 1918 IV 25- V 25 J. Sonan / COType (circular and white label, yellow letters) / Monolepta rufofulva CHÛJÔ DET. M. CHUJO / 2591” (TARI); 1♀ (lack head), same but with “2952” (TARI); 1♀: “ Kankau (Koshun = Henchun, Pingtung) Formosa H. Sauter V. 1912 / COType (circular and white label, yellow letters) / Monolepta rufofulva CHÛJÔ DET. M. CHUJO / 1375” (TARI); 1♀ (only abdomen and right elytron left): “ Hori (= Puli, Nantou) 10-VI-1933 Col., R Takahashi / COType (circular and white label, yellow letters) / Monolepta rufofulva CHÛJÔ DET. M. CHUJO / 1496” (TARI).

Type locality. Kenting National Park, Pingtung County.

Specimens Examined (108 specimens). 4♂♂, 1♀, Hsinchu County, Chienshih, 10.VII.2010, leg. M.-H. Tsou (TARI); 1♀, Hsinchu County, Tahunshan, 8.IX.2009, leg. S.-F. Yu (TARI); 3♂♂, 3♀♀, Kaoshian County, Tengchih, 1. V.2010, leg. Uika Ong (TARI); 1♂, 1♀, same locality, 4.VII.2011, leg. M.-H. Tsou (TARI); 1♀, Kaoshiang County, Tona logging trail, 20.III.2010, leg. Uika Ong (TARI); 1♀, Nantou County, Lienhuachih, 23–26. V.1980, leg. K. S. Lin & B. H. Chen (TARI); 1♂, same locality, 3. VI.2009, leg. C.-F. Lee (TARI); 3♂♂, 6♀♀, Nantou County, Lushan, 27-31. V.1980, leg. K. S. Lin & L. Y. Chou (TARI); 2♂♂, 2♀♀, Nantou County, Nanshanchih, 10.VII.2010, leg. Y.- T. Wang (TARI); 1♂, 1♀, Nantou County, Tungpu, 5-8.X.1981, leg. T. Lin & W. S. Tang (TARI); 1♀, same but with “ 18-23.XI.1981 ” (TARI); 1♀, Nantou County, Wanfengtsun, 2.IV.2008, leg. W.- T. Liu (TARI); 1♀, Nantou County, Wushe, 21. VI.2009, leg. Uika Ong (TARI); 1♂, Pingtung County, Nanjenhu, 1.III.2011, leg. J.-C. Chen (TARI); 3♀♀, same but with “ 11.IV.2011 ” (TARI); 1♂, same but with “ 29.IV.2011 ” (TARI); 1♀, same locality, 27.III.-5.IV.2010, leg. M.-L. Jeng (TARI); 1♂, 1♀, Pingtung County, Shuangliu, 19.VII.2007, leg. M.-H. Tsou (TARI); 3♂♂, Pingtung County, Tahanshan, 18.VII.2007, leg. C.-F. Lee (TARI); 1♀, same but with “ 20.VII.2007 ” (TARI); 1♀, same but with “ 24. VI.2007” (TARI); 1♂, same locality, 18.VII.2007, leg. M.-H. Tsou (TARI); 1♂, 1♀, same but with “ 20.VII.2007 ” (TARI); 1♀, same but with “ 4.VII.2008 ” (TARI); 1♀, same but with “ 27. VI.2010” (TARI); 2♀♀, same locality, 22.II.2007, leg. S.-F. Yu (TARI); 3♂♂, 2♀♀, Pingtung, Wutai, 9. V.2009, leg. Uika Ong (TARI); 1♂, same but with “ 12. V.2009” (TARI); 1♀, same but with “ 17. V.2009 ” (TARI); 1♀, Taipei County, Fushan, 20. VI.2008, leg. H.-J. Chen (TARI); 1♂, 2♀♀, same locality, 26. VI.2011, leg. M.-H. Tsou (TARI); 1♂, Taichung County, Chiapaotai, 14-18.X.1980, leg. K. S. Lin & C. H. Wang (TARI); 2♀♀, Taichung County, Kukuan, 20-22. VI.1978, leg. K. S. Lin & K. C. Chou (TARI); 1♀, same locality, 14-17.X.1980, leg. K. S. Lin & C. H. Wang (TARI); 4♂♂, 4♀♀, Taitung County, Litao, 23. VI.2010, leg. M.-H. Tsou (TARI); 2♀♀, same but with “ 6.X.2010 ” (TARI); 3♂♂, Taitung County, Liyuan, 23. VI.2010, leg. M.-H. Tsou (TARI); 3♂♂, 3♀♀, Taitung County, Motien, 23. VI.2010, leg. M.-H. Tsou (RBCN); 2♀♀, Taitung County, Wulu logging trail, 26.IX.2007, leg. J.-F. Tsai (TARI); 1♂, same locality, 5.X.2010, leg. M.-H. Tsou (TARI); 2♂♂, 2♀♀, same but with “ 24. VI.2010” (TARI); 1♂, 2♀♀, same but with “ 22. VI.2010” (TARI); 1♀, Taoyuan County, Fuhsing, 31.VII.2009, leg. H.-J. Chen (TARI); 1♂, same locality, 28.III.2010, leg. M.-H. Tsou (TARI); 1♂, 1♀, Taoyuan County, Lalashan, 10.X.2009, leg. H. Lee (TARI); 1♂, 1♀, same locality, 19. VI.2010, leg. H.-J. Chen (TARI); 1♀, Taoyuan County, Paling, 16.VII.2010, leg. H. Lee (TARI); 1♂♂, 4♀♀, Taoyuan County, Sankuang, 16.VII.2010, H. Lee (TARI).

Plant Associations. Adults have been observed defoliating Derris laxiflora Benth. (Fabaceae) (Figs. 19–20), Microtropis fokienensis Dunn (Celastraceae), and Lagerstroemia subcostata Koehne (Lythraceae).

Distribution. Monolepta rufofulva occurs in Taiwan in lowlands below 1,500 m elevation (Fig. 16).