Diomus Musant, 1850

Zhuang, Jiamin, Huo, Lizhi, Tang, Mingjie, Xie, Xiufeng & Chen, Xiaosheng, 2023, First report of Diomus guilavoguii Duverger, 1994 (Coleoptera, Coccinellidae, Diomini) predating on papaya mealybug Paracoccus marginatus from China, Biodiversity Data Journal 11, pp. 113291-113291 : 113291

Diomus Musant, 1850

Diomus Scymnus (Diomus) Mulsant, 1850: 951. Type species: Coccinella thoracica Fabricius, 1801, by subsequent designation by Korschefsky (1931).

Diomus Diomus : -Weise (1895: 144); Gordon (1976: 319); Gordon (1999: 13); Pang and Ślipiński (2009: 646).

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

Diomus Amidellus Weise, 1923 - Weise (1923: 141) ( Weise 1923). Type species: Scymnus ementitor Blackburn, 1895 by original designation. Synonymised by Ślipiński (2007: 87).

Diagnosis

This genus can be separated from other genera within the tribe Diomini by the following characters: antennae composed of 11 or 10 antennomeres; slightly shorter than head capsule with pedicel narrower than scape; antennomere 3 elongate; antennal club indistinct and multi-segmented (Fig. 2 d). Abdominal postcoxal lines merging with hind margin of ventrite (Fig. 2 j). For detailed descriptions, see Gordon (1976), Gordon (1999) and Pang and Ślipiński (2009).

Distribution

Worldwide, but certainly more diverse in the Southern Hemisphere like Neotropical and Australian Regions ( Pang and Ślipiński 2009).

Biology

Most species of the genus have a wide range of host preferences that mainly feed on mealybugs (Fig. 1 a), aphids, scale insects and whiteflies. Some species were introduced into various regions for the purpose of biological control. For instance, Diomus pumilio Weise, 1885, originally from Australia, was introduced to California to manage the Albizzia psyllid, Psylla uncatoides (Ferris & Klyver, 1932) (= Acizzia uncatoides (Ferris & Klyver, 1932)), on Acacia ( Gordon and Hilburn 1990).

Figures

Figure 1. Life stages of Diomus guilavoguii Duverger, 1994. a larva, fourth instar; b pupa; c adult, newly emerged; d adult.

Figure 2. Main characters of Diomus guilavoguii Duverger, 1994, adult: a adult in front view; b prothorax, ventral view; c mandible; d antenna; e maxilla; f labium; g hind leg; h front leg; i tarsus of front leg; j abdomen in ventral view. Scale bars: a = 0.2 mm; b, g, j = 200 μm; c, d, e, f, h, i = 50 µm.