Genus Vansomerenis Reinert, Harbach & Kitching, 2006
Vansomerenis pulchrithorax (Edwards, 1939), original combination: Aedes (Finlaya) pulchrithorax.
Subfamily Culicinae, tribe Aedini. Vansomerenis includes three species. Genus abbreviation – Va.
Vansomerenis includes distinctive species that are characterised and distinguished from species of other genera of Aedini by the following combinations of characters. Characters that diagnose Vansomerenis in the phylogenetic analyses of Reinert et al. (2009), based on features observed in Va. luteostriata and Va. pulchrithorax, are indicated by an asterisk (*).
ADULTS – Vertex of head with median pale patch, erect forked scales on vertex and occiput; ocular line with broad silvery scales; eyes contiguous; *antennal pedicel without vestiture on mesal surface (unique character); maxillary palpus and proboscis dark-scaled; scutum with narrow pale stripe on anterior and posterior acrostichal areas extending to prescutellar area, similar stripe on posterior dorsocentral area extending to posterior margin of scutum, longitudinal pale patch on supraalar area, acrostichal setae absent, anterior and posterior dorsocentral setae present; scutellum with narrow scales on all lobes; broad silvery scales on paratergite, antepronotum, postpronotum, upper proepisternum, upper and lower mesokatepisternal areas, lower prealar area and mesepimeron (large patch covering upper and lower areas); lower mesepimeral setae absent; wing dark-scaled, *males with dorsal tertiary fringe scales on proximal 0.50; hindfemur without knee spot, hindtibia with broad basal pale patch, hindtarsomeres 1 and 2 with pale basal bands; both sexes with ungues of all legs each with 1 tooth; laterotergite of abdominal segment I with silvery scale-patch, segment VII of females laterally compressed. FEMALE GENITALIA – Tergum VIII with broad scales on much of surface; sternum VIII wider than long, caudal margin nearly flat or with shallow median emargination, with few to several broad scales, seta 2-S inserted posterior to seta 1-S; tergum IX comprised of 2 long narrow sclerites connected on mesal 0.7 by pigmented band; *cercus without scales, distal part narrowly rounded; *upper vaginal sclerite (as well as lower vaginal sclerite) absent; insula lip-like, with few setae in lateral patches; 3 spermathecal capsules. MALE GENITALIA – Tergum VIII with small posteromedian lobe; tergum IX comprised of 2 small sclerites connected mesally by tongue-like median anteriorly directed lobe of tergum X, each sclerite with small posterior lobe bearing few setae, lateral part of lobe connected by narrow band with sternum IX; gonocoxite with scales on dorsal surface, without apicomesal lobe, with basal lobe, distal part of lobe with 2 or 3 setae, proximal part expanded with series of basal wrinkles and several setae (*one or more stout or flattened), mesal surface of gonocoxite membranous; gonostylus attached at apex of gonocoxite, with single apical gonostylar claw; aedeagus simple, tube-like; claspette comprised of long slender columnar stem with long distally expanded and flattened claspette filament. LARVAE – Antenna with few scattered spicules, seta 1-A single or double, occasionally triple; seta 4-C inserted mesal and slightly posterior to seta 6-C; seta 5-C often single (1–3-branched), inserted posteromesal to seta 6-C and posterolateral to seta 4-C; seta 6-C longer than seta 5-C, inserted mesal and very slightly anterior to seta 7-C; seta 12-C inserted mesal to and shorter than seta 13-C; seta 19-C absent; *seta 4-P not longer than seta 3-P; seta 5-P branched, shorter than seta 6-P; seta 6-I,II long, branched (6-II rarely single in Va. luteostriata), seta 6-III branched, shorter than 6-II; seta 7-I long, double or triple, 7-II short, multi-branched; comb comprised of numerous scales in patch; *seta 1-VIII ≥ 1.10 length of seta 2-VIII; seta 2-VIII branched; pecten spines of siphon evenly spaced; seta 1-S branched, inserted distal to pecten; saddle of segment X incomplete ventrally, acus absent; setae 1-X branched, inserted on saddle; ventral brush (seta 4-X) with 2 precratal setae, other setae inserted on grid with well-developed transverse grid bars, lateral bars absent, represented by faint depression. PUPAE – Seta 7-CT very long, longer than 6 times length of seta 6-CT; seta 6-I single, very long, noticeably longer than seta 7-I; seta 7-I usually double, rarely single or triple; seta 2-II inserted lateral to seta 1 and mesal to seta 3, seta 2-VI inserted mesal to setae 1 and 3; seta 3-II,III long, stout, single; seta 5-II shorter than seta 3-II; seta 6-II longer than seta 7-II; seta 7-II longer than following tergum; *seta 2-V inserted anterior to seta 3-V; seta 6-VII inserted posteromesal to seta 9-VII; seta 9-VIII inserted near posterolateral corner of segment; paddle longer than wide, paddle index 1.20–1.42, without hair-like spicules on margins; seta 1-Pa single. See Aedini.
The phylogenetic relationships of Vansomerenis are uncertain. The genus was recovered as the sister of Zavortinkius + Kenknightia in a clade comprised of (Himalaius + Bruceharrisonius) + (Vansomerenis + (Zavortinkius + Kenknightia)) in the phylogeny of Reinert et al. (2009) based on morphological data. Relationships of Vansomerenis with other generic-level taxa of tribe Aedini were not resolved in the phylogeny of Wilkerson et al. (2015).
The immature stages of species of Vansomerenis have been found in tree holes, a rot hole in the fork of a tree, a tree buttress and bored bamboo. Nothing is known about the bionomics of the adults, which are only known from larval rearings.
The species of Vansomerenis are not of medical and economic importance to humans.
Species of Vansomerenis are known to occur in six central African countries: Angola, Democratic Republic of the Congo, Kenya, Tanzania, Uganda and Zambia.
Reinert et al., 2006, 2008, 2009 (generic status, morphology, phylogeny); Reinert, 2008 (female genitalia); Huang & Rueda, 2017 (as Pulchrithorax Group of Aedes subgenus Finlaya, Afrotropical Region, key to adults); Wilkerson et al., 2015 (as subgenus of Aedes, phylogeny).
