Aedes (Stegomyia) ealaensis, Yiau-Min Huang, 2004

Yiau-Min Huang, 2004, The subgenus Stegomyia of Aedes in the Afrotropical Region with keys to the species (Diptera: Culicidae), Zootaxa 700, pp. 1-120 : 36-39

Aedes (Stegomyia) ealaensis New Species

( Figs. 11 A,C,D,E; 12A,B; 37B)

FEMALE. Head. Proboscis dark­scaled, without pale scales on ventral surface, longer than forefemur (1.03–1.09 length of forefemur); maxillary palpus 0.21–0.22 length of proboscis, dark, with white scales on entire dorsal surface of palpomere 3; pedicel covered with white scales except on dorsal surface; antenna with a few dark scales on flagellomere 1; clypeus bare; occiput with few erect forked scales; a row of broad white scales around eye margins; vertex with a median stripe of broad white scales, with broad dark scales on each side interrupted by lateral stripe of broad white scales, followed ventrally by a patch of broad white scales. Thorax ( Fig. 11 A). Scutum with narrow dark scales, and a distinct median stripe of broad white scales on anterior promontory, with a short median longitudinal stripe of narrow pale yellowish scales, reaching to prescutellar area, absent in anterior 0.50–0.66 of scutum; prescutellar line of narrow pale yellowish scales not present; fossal area with a large patch of broader crescent­shaped white scales; posterior dorsocentral pale yellowish line of narrow scales present, reaching to posterior 0.33–0.40 of scutum; a patch of narrow white scales on lateral margin just in front of wing root; acrostichal setae absent; dorsocentral setae present; scutellum with broad white scales on midlobe and with a few broad dark scales at apex of midlobe, with broad dark scales on lateral lobe; antepronotum with broad white scales; postpronotum with a large patch of broad white scales and a few dark narrow scales dorsally; paratergite with broad white scales; postspiracular area without scales; hypostigmal area without scales; patches of broad white scales on propleuron, subspiracular area, upper and lower portions of mesokatepisternum, and on mesepimeron; upper mesokatepisternal scale patch not reaching to anterior corner of mesokatepisternum; upper mesepimeral scale patch connecting with lower mesepimeral scale patch, lower mesepimeral scale patch much reduced, or absent; lower mesepimeron without setae; metameron and mesopostnotum bare. Wing. With dark scales on all veins and without a minute basal spot of white scales on costa; cell R2 2.8–3.7 length of vein R2+3. Halter . With dark scales. Legs ( Figs. 12 B; 11D). Coxae with patches of white scales; white knee­spot absent on forefemur, present on mid­ and hindfemora; forefemur anteriorly dark, with a subapical white stripe on ventral surface in apical 0.33; midfemur with a large, white spot on anterior surface 0.59–0.62 from base, usually with some white scales scattered on anterior surface in basal 0.5 and in apical 0.33; hindfemur anteriorly with a broad, white longitudinal stripe in basal 0.58–0.61; foretibia anteriorly dark with a basal white band; midtibia anteriorly dark, usually with a basal white spot on posterior surface; hindtibia anteriorly with a white longitudinal stripe on ventral surface in basal 0.43–0.52 that narrows 0.20–0.23 from base and not expanded on to anterior surface; foretarsomere 1 with basal 0.11­0.14 white on dorsal surface; foretarsomere 2 with basal 0.30–0.42 white on dorsal surface; midtarsomere 1 with basal 0.18–0.20 white on dorsal surface; midtarsomere 2 with basal 0.91­0.92 white on dorsal surface; hindtarsus with a basal white band on tarsomeres 1­5, the ratio of length of white band on dorsal surface to the total length of tarsomere is 0.25–0.27, 0.24–0.30, 0.19–0.23, 0.35–0.40 and 0.27–0.44; fore­ and midlegs with tarsal claws equal, all toothed; hindleg with tarsal claws equal, both simple. Abdomen ( Fig. 11 C). Tergum I with white scales on laterotergite; terga II–IV with basolateral white spots only; terga V­VIII each with a basal white band and basolateral white spots which do not connect with the basal white band; basal white band on tergum V usually not complete on middle; basal white band on terga VI–VII usually rather long, extending to 0.8–0.9 length of tergum; sterna III–VII each with a basal white band.

MALE. Essentially as in the female, differing in the following sexual characters: Head. Maxillary palpus longer than proboscis, predominantly dark, with a white band at base of palpomeres 2­5, those on palpomeres 4, 5 dorsally incomplete; palpomeres 4, 5 subequal, slender, dorsally curved and with only a few short setae; antenna plumose, shorter than proboscis. Wing. Cell R2 2.0–2.2 length of vein R2+3. Legs ( Figs. 12 A; 11E). Fore­ and midlegs with tarsal claws unequal, the smaller one toothed, the larger one simple. Abdomen. Terga III–VII each with a basal white band and basolateral white spots which do not connect with the basal white band; sternum VIII with basolateral white spots.

Genitalia ( Fig. 37 B). Gonocoxite 2.1 times as long as wide (width measured 0.5 from base); claspette large, lobed, distal expanded portion square in dorsal aspect, apicomesal angle formed a thumb­like projection, with numerous simple setae on the expanded distal portion and bearing 9 setae at tip of the projection, with apicolateral corner rounded; gonostylus rather short, curved, 0.52–0.56 length of gonocoxite, with a short, stout claw process at apex; paraproct with a sternal arm; cercal setae absent; apical margin of tergum IX concave medially with 7–8 setae on lateral lobe; sternum IX without setae.

PUPA and LARVA. Unknown.

TYPE DATA. Holotype male (MEP Acc. 725/ #3003, Eala, I­1933, Dr. C. Henrard), with genitalia on slide (MEP Acc. 725, 81/165), Eala (0o 01' N, 18o 30' E), Cuvette­Centrale, DEMOCRATIC REPUBLIC OF THE CONGO ( Zaire), I­1933 (Dr. C. Henrard). Deposited in the Department of Zoologie, Section d’Entomologie, Musee Royale de l’Afrique Centrale, Tervuren, Belgium [CMT]. Allotype female (MEP Acc. 725/ #3003), same data as holotype [CMT]. Paratypes: 3 males and 1 female as follows, (MEP Acc. 725): 1 male (#3003), with genitalia on slide (81/166), 2 males (#2800), with genitalia on slides (81/137, 81/138) and 1 female (#3003), with genitalia on slide (81/139), same data as holotype. Deposited in the CMT.

OTHER MATERIAL EXAMINED. DEMOCRATIC REPUBLIC OF THE CONGO ( Zaire). Cuvette­Centrale: Coquilhatville (0° 04' N, 18° 20' E), 10­II­1945, J. Wolfs, 1 F, 1 F gen (MEP Acc. 725, 81/140) [CMT]; same data except 1945, J. Wolfs, 1 F (MEP Acc. 725) [CMT]; same data except 1­III­1946, J. Wolfs, 1 F, 1 F gen (MEP Acc. 725, 81/171) [CMT]. Haut­Congo: Yangambi (0° 50' N, 24° 15' E), no date, Dr. Parent, 1 M, 1 M gen (MEP Acc. 725, 81/167) [CMT].

DISTRIBUTION. This species is known only from Democratic Republic of the Congo ( Zaire).

TAXONOMIC DISCUSSION. Aedes ealaensis is a member of the apicoargenteus group. The apicoargenteus group can be distinguished from other Stegomyia species by the following combination of characters: (1) scutum with a distinct patch of broader crescent­shaped white scales on fossal area; (2) white knee­spot absent on forefemur, present on mid­ and hindfemora; (3) midfemur with a large, white spot on anterior surface; (4) hindtibia anteriorly dark, with a white stripe in subbasal area and (5) abdominal basal white band on terga VI–VII rather long, extended to 0.5–0.9 length of tergum.

Aedes ealaensis has the scutellum with broad white scales on the midlobe and broad dark scales on the lateral lobes, and can thus be easily distinguished from all other species of the apicoargenteus group except Ae. apicoargenteus and Ae. denderensis .

The adult male and female of Ae. ealaensis are very similar to those of Ae. apicoargenteus , but can be distinguished from those of Ae. apicoargenteus by the hindtarsomere 5 with basal 0.27–0.44 white on dorsal surface. In Ae. apicoargenteus , the hindtarsomere 5 is entirely dark.

The adult males and females of Ae. ealaensis are easily confused with those of Ae.

denderensis , but can be distinguished by the hindtarsomere 4 with basal 0.35–0.40 white on dorsal surface and hindtarsomere 5 with basal 0.27–0.44 white on dorsal surface. In Ae. denderensis , the hindtarsomere 4 has basal 0.89–0.94 white on dorsal surface and hindtarsomere 5 has basal 0.33 white to all white on dorsal surface.

The male genitalia of Ae. ealaensis are easily differentiated from all other species in the apicoargenteus group by the claspette, which has the distal expanded portion square in dorsal aspect, apicomesal angle formed a thumb­like projection, with numerous simple setae on the expanded distal portion and bearing 9 setae at the tip of the projection, with apicolateral corner rounded, and by the gonostylar claw, which is short and stout.

Aedes ealaensis is most similar to Ae. denderensis . Based on the present collection data, Ae. ealaensis occurs in habitats with altitudes between 333 and 400 m in areas of yearly rainfall of 177.80 cm.

BIONOMICS. Unknown.

MEDICAL IMPORTANCE. Unknown.

Figures

FIGURE 11. Aedes (Stg.) ealaensis — A, thorax (dorsal view); C, female abdomen (dorsal view); D, female tarsal claws (fore­, mid­ and hindlegs); E, male tarsal claws (fore­, mid­ and hindlegs); Aedes (Stg.) denderensis — B, thorax (dorsal view).

FIGURE 12. Aedes (Stg.) ealaensis — A, male (Holotype) fore­, mid­ and hindlegs (anterior view); B, female fore­, mid­ and hindlegs (anterior view); Aedes (Stg.) denderensis — C, female fore­, mid­ and hindlegs (anterior view).

FIGURE 37. Aedes (Stg.) denderensis — A, male genitalia; Aedes (Stg.) ealaensis — B, male genitalia.