Megalotomus acutulus Liu & Liu, 1998

Yi, Wenbo, Wang, Shijun, Zhang, Hufang & Bu, Wenjun, 2022, Notes on Megalotomus Fieber, 1860 in the Palaearctic Region (Hemiptera, Heteroptera, Alydidae), Zootaxa 5128 (2), pp. 211-224 : 219

Megalotomus acutulus Liu & Liu, 1998

( Figs. 20–22 , 38–40 )

Megalotomus acutulus G.Q. Liu & Q. Liu, 1998: 41 . Holotype: ♂, China (North), Inner Mongolia, Hailar (49.2°N / 119.7°E); NKUM. Dolling, 2006: 38.

Diagnosis. This species is recognized within the genus Megalotomus by a combination of the following characters: body size relatively moderate, 12.5–14.0 mm in length, yellowish brown to black, with black punctures; head and pronotum with long, dense pilosity; vertex black, with pale yellow midline and macula on both sides; posterior angle of pronotum slightly upward, not sharp; forewings with small, light-coloured spots, and anterolateral margin pale; meta-femora with 3–5 spines on the inner margin of the terminal half, becoming gradually longer from proximal to terminal; surcapsular spines of the genital capsule acute and straight, extending without any projection or bifurcation; parameres strongly curved upward, elongate and slender, tapering gradually towards apex, and each with one or two prominent acute projections in the middle on the inner side.

Material examined. China: Hebei Province: 1 ♂, Xiaowutaishan National Nature Reserve, Donglingshan , 1700 m, 21-August-2005, Xin Yu leg. ( NKUM) ; Inner Mongolia: 3 ♂♂, 1 ♀, Chifeng City, Keshiketeng Banner, Daerhansumu , 1240 m, 9-August-2008, Xueqin Shi leg. ( NKUM) ; Shanxi Province: 4 ♂♂, 1 ♀, Xinzhou City, Wutai County, Taihuai Town , Wutaishan National Nature Reserve , Xinyinsi Temple , 39.01°N, 113.63°E, 1844 m, 13-August-2020, Wenbo Yi leg. ( XZTU) ; 9 ♂♂, 4♀♀, Xinzhou City, Wutai County, Taihuai Town , Wutaishan National Nature Reserve , Loushang Village , 39.00°N, 113.65°E, 1924 m, 13-August-2020, Wenbo Yi leg. ( XZTU) ; 8 ♂♂, 3 ♀♀, Xinzhou City, Wutai County, Taihuai Town , Wutaishan National Nature Reserve , Muwagou , 39.03°N, 113.62°E, 1849 m, 14-August-2020, Wenbo Yi leg. ( XZTU) .

Distribution. China (Hebei, Inner Mongolia, Shanxi).

Remarks. This species is readily recognized within the genus Megalotomus by its diagnostic characters, as thoroughly described and illustrated in Liu & Liu (1998). During field work in Wutaishan National Nature Reserve, Shanxi Province, China, large amounts of adults of this species were found on Melilotus officinalis , a common herbaceous plant of Leguminosae, which is highly suspected to be the host plant of this species, since there are no previous host records.

Figures

FIGURES 17–22. Megalotomus spp., dorsal, lateral and ventral views. Figs. 17–19, M. zaitzevi Kerzhner, 1972, male (China: Xinjiang Autonomous Region, Yuli County); Figs. 20–22, M. acutulus Liu & Liu, 1998, female (China: Inner Mongolia, Chifeng City, Keshiketeng Banner). Figs. 17 and 20, dorsal view; Figs. 18 and 21, lateral view; Figs. 19 and 22, ventral view. Scale in mm.

FIGURES 23–43. Male genitalia of Megalotomus spp. and Alydus calcaratus (Linnaeus, 1758). Figs. 23–25, M. angulus (Hsiao, 1965) comb. nov.; Figs. 26–28, M. junceus (Scopoli, 1763); Figs. 29–31, M. ornaticeps (Stål, 1858); Figs. 32–34, M. castaneus Reuter, 1888; Figs. 35–37, M. zaitzevi Kerzhner, 1972; Figs. 38–40, M. acutulus Liu & Liu, 1998; Figs. 41–43, Alydus calcaratus (Linnaeus, 1758); Figs. 23, 26, 29, 32, 35, 38, 41, genital capsules, dorsal view, parameres removed, pilosity only shown on left side; Figs. 24, 27, 30, 33, 36, 39, 42, left parameres, dorsal view; Figs. 25, 28, 31, 34, 37, 40, 43, same, lateral view. Scale in mm.