Sepiomus Aurivillius, 1891

Yunakov, Nikolai, Korotyaev, Boris & Alziar, Gabriel, 2024, Miscellaneous notes on the systematics of and synonymy in Entiminae (Coleoptera, Curculionidae), Contributions to Entomology 74 (2), pp. 249-264 : 249-264

Genus Sepiomus Aurivillius, 1891 , reestablished tribal placement

Fig. 2

Sepiomus Aurivillius, 1891: 211, type species by original designation Episomus parallelus Chevrolat, 1883 (classified as Cyphicerini); Marshall 1944: 74 (classified as Leptopiinae); Alonso-Zarazaga and Lyal 1999: 187 (classified as Tropiphorini = Byrsopagini).

Material examined.

Sepiomus frontalis Aurivillius, 1891 : CAMBODIA • 1 ♂; “ Kirirom / (Cambodge) ”; M. André leg.; GAC . Sepiomus parallelus Chevrolat, 1883 : CAMBODIA • 1 ♂; “ Kiri Rom / (Cambodge) ”; M. André leg.; GAC (Fig. 2 A ) • 1 ♀; “ Kirirom / ( Cambodge) ”; M. André leg.; GAC . • 1 ♂, 3 ♀; “ Indochine ”; GAC .

Discussion.

Sepiomus was established for three Indo-Chinese species: Episomus parallelus Chevrolat, 1883 from Cambodia and Vietnam, Sepiomus frontalis Aurivillius, 1891 and S. tuberculatus Aurivillius, 1891 from Cambodia. Later, Faust (1895 a) described a Vietnamese species, S. aurivilliusi Faust, 1895 , and added to this genus another Vietnamese species Corigetus figulus Faust, 1893 ( Faust 1895 b), characterized by thin antennal funicle and a widened base of the antennal scape in females. Subsequently, Heller (1925) described Sepiomus tuberculatus microscutellaris Heller, 1925 from North Sumatra, and Vayssière (1941) discovered S. casuarinae Vayssière, 1941 in Vietnam.

Some Cyphicerini in South-East Asia exhibit specific modifications of the head capsule and body vestiture resembling those of Episomus Schoenherr, 1823 , such as the Formosan weevil Episomoides albinus (Matsumura, 1910) ( Kôno 1930) .

Sepiomus was originally classified in Cyphicerini . Marshall 1944 while revising the genera of Cyphicerini proposed a new classification based on the chaetotaxy of prementum and mandibles. According to this classification, Cyphicerini genera have 3 - setose mandibles, thus genera Sepiomus and Cylindromus having 4 - setose mandibles were transferred to Leptopiinae. Alonso-Zarazaga and Lyal (1999) conventionally retained it in Tropiphorini .

We transfer Sepiomus to Cyphicerini based on the deeply emarginate epistome (Fig. 2 B ), the prementum concealing the maxillae (Fig. 2 D , pr), and male genitalia typical for this tribe: median lobe significantly shorter than apodemes and possessing apical preostial process (Fig. 2 E , ml-app); endophallus very long, unfolded from median lobe, and bearing large fields of abundant, dense spiculae; sternite 8 consists of heavily sclerotized, broadly lanceolate hemisternites with long setae along the posterior margin (Fig. 2 F , Mst 8). Sepiomus may be placed in the subtribe Cyphicerina based on the presence of postocular lobes (Fig. 2 C ).

Figures

Figure 2. Sepiomus parallelus, male: A. Body dorsal and lateral view; B. Head dorsal view; C. Head lateral view; D. Head ventral view; E. Aedeagus dorsal and lateral view; F. Sternite 8 and 9. Abbreviations: ml-app – apical preostial process of median lobe; Mst 8 – sternite 8; pr – prementum.