Diomus Mulsant, 1850

Genus Diomus Mulsant, 1850 View in CoL

Scymnus (Diomus) Mulsant, 1850: 951 , Korschefsky, 1931: 116, Mader, 1955: 955, Bielawski 1973: 399. Type species: Coccinella View in CoL thoracica Fabricius, 1801, by subsequent designation of Korschefsky, 1931.

Nephus (Diomus) : Iablokoff-Khnzorian, 1976: 377.

Diomus View in CoL : Weise, 1895: 144, Chapin, 1933: 95; Gordon, 1976: 319; Pang & Gordon, 1986: 192; Gordon, 1999: 13; Ślipiński, 2007: 87; Pang & Ślipiński, 2009: 646; Vandenberg & Hanson, 2018: 262 View Cited Treatment .

Amidellus Weise, 1923: 141 . Type species: Scymnus View in CoL ementitor Blackburn, 1895, by original designation. Synonymized by Ślipiński, 2007: 87.

Diagnosis. In Chinese fauna of Diomus , it can be distinguished from other morphological similar coccinellids, especially within some genera of Scymnini by the following combination of characters: antenna composed of 10 or 11 antennomeres and only slightly longer than half of head capsule, terminal maxillary palpomere securiform and strongly

expanded apically, prosternal intercoxal process with carinae extending to anterior margin, abdominal ventrite 1 and 2 at middle fused, abdominal postcoxal lines descending and merging with posterior margin of ventrite 1, and coxites short and distinctly transverse.

Distribution. Worldwide.

Key to the native species of Diomus View in CoL from China.

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4. Tegmen with penis guide longer than parameres in lateral view ..........................................................................................................2 Tegmen with penis guide shorter than parameres in lateral view .........................................................................................................3 Penis capsule with shorten and weak outer arm; penis guide widest at base, gradually tapering to pointed apex in inner view; penis guide wide and not constricted at near base, narrowed to an acute tip in lateral view ............................................... D. akonis (Ohta) Penis capsule with elongate and swollen outer arm; penis guide constricted at base and widest at middle in inner view; penis guide constricted at near base, broaden to middle, then narrowed to pointed apex in lateral view ......................... D. lantauensis Yu & Lau Elytra only black in middle; abdominal postcoxal lines without associate lateral lines; posterior margin of ventrite 1 straight, ventrite 2 uniformly wide; penis capsule with shorten and subtriangular inner arm .........................................................................................4 Elytra almost entirely black; abdominal postcoxal lines with short oblique associate lateral lines; ventrite 1 posteriorly medially arcuate, ventrite 2 at middle narrower than both sides; penis capsule with long and well-developed inner arm....................................

...................................................................................................................................... D. dafushanensis Bi, Peng & Chen , sp. nov. Penis capsule with distinctly elongate and broaden out arm; parameres swollen and broad in lateral view............... D. tumefactus Yu Penis capsule with relatively shorten out arm; parameres relatively slender and long in lateral view ....................... D. longilobus Yu