Christophersiomyia thomsoni (Theobald, 1905), original combination: Stegomyia thomsoni.
Subfamily Culicinae, tribe Aedini. Christophersiomyia includes five species. Genus abbreviation – Cr.
Species of Christophersiomyia are easily distinguished from those of other genera of tribe Aedini that occur in the Oriental and Australasian Regions by one or more of the distinctive features listed below. Characters (21) that diagnose the Christophersiomyia clade recovered in the cladistic analysis of Reinert et al. (2009) are preceded by an asterisk (*). ADULTS – Ornate; vertex of head with broad decumbent scales; erect scales confined to occiput; *proboscis with pale scales form *band near midlength; maxillary palpus short, comprised of 3 palpomeres (both sexes); acrostichal setae and *dorsocentral setae absent; scutellum with broad decumbent scales; paratergite, postprocoxal membrane, *lower prealar area (below prealar knob) and *metameron with scales; *lower mesepimeral setae present; *dorsal tertiary fringe scales present on proximal 0.5 of wing in males; legs usually with bands or spots of pale scales; both ungues of all legs, notably hindungues of *males and *females, both toothed; laterotergite of abdominal segment I completely covered with scales; *segment VII dorsoventrally flattened. FEMALE GENITALIA – Segment VIII completely retracted; *tergum VIII with setae on distal 0.7, *posterior margin convex. MALE GENITALIA – Tergum IX long, ninth tergal lobes short, each with group of short setae; gonocoxite imple, without lobes, with scales on lateral and ventral surfaces; gonostylus simple; gonostylar claw a *relatively narrow spiniform, with *truncate apex; claspette a small poorly developed lobe with numerous simple setae; aedeagus *widest in distal third, apparently formed of 2 lateral plates with distal parts strongly curved mesally and fused apically, without teeth (except Cr. gombakensis); proctiger poorly sclerotised except for paraproct, paraproct with single stout tooth; cercal setae absent. LARVAE – Median labral plate extremely narrow, indistinct; seta 1-C very long, slender; antenna with seta 1-A inserted near midlength; *seta 3-P longer than seta 2-P; *seta 4-P shorter than seta 3-P; *seta 5-P single; *seta 8-P >1.8 times length of seta 4-P; seta 12-I absent; *seta 1-VIII >1.1 times length of seta 2-VIII; comb scales spine-like with fine basal fringes, in single row; siphon short to moderately long, siphon index 2.0–4.0, acus absent or small and detached; saddle incomplete; seta 2-X double; ventral brush (seta 4-X) with 4 pairs of setae, grid or boss absent. PUPAE – Seta 1-CT long, single to 7-branched; *seta 3-I shorter than seta 6-I; paddle ovoid, midribe ends before apex; seta 1-Pa long, *0.4–0.6 paddle length, normally single. See Aedini.
Belkin (1962) and Abercrombie (1977) surmised that Christophersiomyia (as a subgenus of Aedes) has closest affinities with Stegomyia and Bothaella, respectively, but this is not supported by the phylogenetic study of Reinert et al. (2009) in which Christophersiomyia was placed in a clade comprising a pectinate series of other genera: Polyleptiomyia + (Bifidistylus + (Albuginosus + (Tewarius + (Christophersiomyia) + Huaedes + Leptosomatomyia))))). Further research is needed to confirm these relationships.
Species of Christophersiomyia are rarely collected and little is known of the bionomics. The immature stages have been found in tree holes, stump holes, water butts, woodpecker holes, rock pools of streams, coconut shells and spathes. The females of several species have been collected feeding on humans.
Species of Christophersiomyia are of no medical or economic importance to humans.
Christophersiomyia species occur in the Oriental Region, Papua New Guinea and Solomon Islands.