Subgenus Orohylomyia Somboon & Harbach, 2023

Type species: 

Aedes yunnanensis (Gaschen, 1934), original combination: Finlaya yunnanensis.


Subfamily Culicinae, tribe Aedini, genus Aedes. Subgenus Orohylomyia is monobasic. Subgenus abbreviation – Oro.


The single species of Orohylomyia is most similar to species of the subgenera Collessius, Gilesius, Hulecoeteomyia and Tanakaius. Significant similarities include the scutal ornamentation of adults and the linear arrangement of setae 4–6-C of the larva. Adults of Orohylomyia, Gilesius and Ae. savoryi of subgenus Tanakaius differ from adults of Collessius and Hulecoeteomyia in having hindtarsomeres 1–3 entirely dark-scaled (these tarsomeres have basal pale bands in species of Hulecoeteomyia and Ae. togoi of subgenus Tanakaius and basal and apical pale bands in species of Collessius). The adults (both sexes) of Ae. yunnanensis and Tanakaius differ from those of Collessius, Gilesius and Hulecoeteomyia in having the hindungues with a median tooth (the hindungues are simple, without a tooth, in species of Collessius, Gilesius and Hulecoeteomyia).

ADULTS – Antennal pedicel with scales on mesal and dorsal surfaces; flagellomere 1 with mesal patch of scales; maxillary palpus of females usually with some pale scales apically, maxillary palpus of males with pale scales on dorsal surface of palpomeres 1 and 2; proboscis dark-scaled, longer than forefemur in females, shorter than forefemur in males; scutum with acrostichal setae, acrostichal and anterior dorsocentral areas with pale scales, acrostichal line forked posteriorly at sides of prescutellar bare space, pale scales laterally from anterior promontory to margins of scutal fossa and along inner side of supraalar area to posterior margin of scutum, supraalar area with narrow pale falcate scales; paratergite with narrow pale scales; patches of broad pale scales on postspiracular area, subspiracular area, prealar area and upper mesokatepisternum; lower mesepimeral seta absent; wing dark-scaled, with few pale scales at extreme base of costa; midfemur with anterior stripe of pale scales on proximal 0.8, tarsi of all legs entirely dark-scaled; females with ungues of all legs equal, each with a median tooth, males with unequal fore- and midungues, larger unguis with a median tooth, smaller unguis with a basolateral tooth, hindungues as in females; abdominal terga dark-scaled with basal pale bands on terga II–VIII, females with segment VII dorsoventrally flattened and segment VIII not retracted into segment VII. FEMALE GENITALIA – Tergum IX 1.3 times wider than long, with convex posterior margin and about 18 more or less stiff simple setae on posterolateral areas; cerci broad, moderately long; postgenital lobe with slight caudal emargination, insula pad-like, with 2 irregular rows of 4 or 5 setae; 1 large and 2 smaller spermathecal capsules. MALE GENITALIA – Ninth tergal lobes small, widely separated by narrow faintly developed bridge, lobes with short simple setae; gonocoxite with row of long narrow lanceolate setae along distal 0.5 of ventromesal margin; gonostylus elongate, curved, tapered toward apex, proximal portion distinctly stouter than distal portion, with long slender gonostylar claw at apex; claspette filament long, slender, cylindrical, sickle-shaped, slightly acuminate apically, borne at apex of elongate tubular stem, about twice length of stem; paraproct long, slender, strongly sclerotized, with more strongly sclerotized beak-like apex. LARVAE – Antenna about 0.33 length of dorsal apotome, moderately spiculate; seta 1-A with 2–4(4) aciculate branches, inserted more or less at mid-length of shaft; setae 4–6-C arranged in a transverse row, 4-C small, weak, inserted about same level as 5-C, 5,6-C fan-like with strong aciculate branches, 6-C longer than 5-C; seta 7-C inserted on level posterior to 5-C; setae 5,10,12-M and 10-T long, double, aciculate; comb scales in patch, scales evenly fringed at sides and apex; siphon short, stout, pecten slightly longer than 0.5 siphon length, seta 1-S inserted at or slightly beyond distal pecten spine; saddle incomplete, posterior margin with short needle-like spicules; seta 1-X single, 2-X with 3 or 4 branches, 3-X usually double; ventral brush (seta 4-X) comprised of 12 setae inserted on grid with lateral and transverse grid bars. PUPAE – Seta 1-CT usually single, longer than 3-CT; seta 11-CT well developed, single, long, stiff, inserted immediately lateral to 10-CT; seta 1-II well developed, multi-branched; seta 2-VI inserted mesad of 1-VI; setae 3-II,III and 5-IV–VII long, single; seta 6-VII usually single, inserted immediately posteromesad to 9-VII; seta 9-VII dissimilar to 6-VII, much stronger and longer than 6-VII, single or with 2 or 3 apical branches, 9-VIII more strongly developed than 9-VII, branched at base, with 4–8 aciculate strong branches; paddle broad, asymmetrical, inner part narrower proximally and broader distally than outer part, emarginate at termination of midrib, distal inner and distal outer margins spiculate; seta 1-Pa single, inserted on edge of outer part immediately adjacent to apex of midrib; seta 2-Pa absent. See genus Aedes.

Phylogenetic relationships: 

In a phylogenetic analysis of mtDNA COI sequences (Somboon et al., 2023), Ae. yunnanensis formed a strongly supported lineage in an unresolved relationship with species of the subgenera Collessius (Alloeomyia Group) and Gilesius, leaving no doubt that Ae. yunnanensis is not a member of the subgenus Hulecoeteomyia in which it was previously classified. It is interesting to note that Hulecoeteomyia was recovered, albeit weakly, as the sister to all other taxa included in the analysis, i.e., in addition to Orohylomyia, species of 12 other subgenera of Aedes and a species of uncertain subgeneric placement.

Bionomics and disease relations: 

The immature stages of the type species of Orohylomyia have been found in small groundwater habitats and artificial containers, including buckets, cement tanks, crevices in rocks, iron pans, oil drums, ponds, puddles, rock pools, rocky caves, stagnant pools, stone pits, stone troughs and tyres in mountainous terrain at elevations above 1,000 m (Gaschen, 1934; Lei, 1989; Lu et al., 1997; Dong et al., 2009; Somboon et al., 2023). Nothing is known about the biting behavior of females and whether or not they may vector pathogenic agents.


The only known species of Orohylomyia has been collected at localities in Guizhou, Sichuan and Yunnan Provinces of China (Gaschen, 1934; Lei, 1989; Lu et al., 1997; Dong et al. 2009; Somboon et al., 2023).

Principal references: 

Knight & Marks 1952 (as species of Group H (Geniculatus-group: Protomacleaya) of subgenus Finlaya); Lei, 1989 (as species of subgenus Finlaya, in key, description, bionomics, distribution); Lu et al., 1997 (as species of dissimilis group of subgenus Finlaya, in key, description, bionomics, distribution); Dong et al. 2009 (as species of Ochlerotatus yunnanensis group of subgenus Finlaya, in keys, description, bionomics, distribution); Somboon et al., 2023 (new subgenus, China, taxonomy, description of subgenus and type species, bionomics, distribution, phylogenetic relationships).


yunnanensis (Gaschen, 1934)

Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith