PLATE XIV.
f\ 1 f %l^ The genera Stegomyia and Armigeres. 1, S. notoscripta, Skuse ; 2 and 3 S. fasciata (Fabr.) ; 4 and 5, S. scutellaris, Walk. ; 6 and 7, S. Qubernatoris, sp. n. ; « and 9 6. pseudotmnata, sp. n. ; 10, larva of the same species, less amphfied; 11, Wing of Ar. ventralis, Walk.; 12, Pore, mid and hind tarsal claws of the same ; 13, Wing of Ar. panalectoros, sp. n. ; 14, Head and appendages, and 15, Fore, mid and hind tarsal claws of the same; 16, Head and thorax of the same ; 17 to 20, S. brevipalpis, sp. n. ; 21, S.irritans; 22, S periskelata, sp. n. ; 23, Mdes,nigricor'pus, Theob. ; 24 to 26, S. microptera sp. n.' Fare p.
384.
GENUS ARMIGERES 385 minuta, but they differ in the form of the male palpi which are long and tapering, much as in Janthinosoma, from which genus, however, they differ in the form of the head scales. In the B.M. Monograph, it originally included but one species, Ar. ventralis (Walker) = C. ohtarhans, Walker, and both Mr. Theobald and myself have gone through various changes of opmion, as to whether the specimens included in our collections should be regarded as anything from four to one species. We both now, however, think that there are sufficient grounds for distinguishmg two forms, which were sent me from Calcutta, sorted roughly into species, by Major Allcock, the Huperintendent of the Indian Museum. In ordinary pinned specimens it may be admitted that they are hard to distinguish, but when unrubbed, there is no particular difficulty in doing so. One of these forms, with a dark thorax, paler externally but quite undecorated in the middle, is undoubtedly AValker's C. ventralis. which appears to be quite indistinguishable from his ohturhans. I have carefully examined the rather long series in the museum collection, and though the thorax is m excellent preservation in many of them, I cannot distinguish, in any one of them, the markings which distinguish the other and smaller species described below, which has the thorax rtither elaborately, though not very conspicuously, decorated, and differs somewhat in the form of the tarsal claws. The collection received from Calcutta was sorted into three forms, one of which I thought might be identical with Skuse's C. atripes, distinguished by the tarsal claws of the <? being of nearly equal length ; but this character appears to vary soniewhat in Ar. ventralis, and in any case it is quite distinct from Skuse's species, as specimens received from Australia show that this is a true Culex.
1. ARMIGERES VENTRALIS (Walker).
Proc. Linn. See. Lond. v, p. 144 ; iv, p. 91. = C. obturhans. Plate xiv, fig. 11, Venation of wing ; 12, Tarsal claws of ^ . Wing veins clothed with rather scanty but intensely black scales, short and close setting towards the base, and linear and outspread on the outer part of the wing. Tarsi uniformly sooty, smooth scaled. Thorax with dark brown ground, and the mesonotum uniformly clothed with long hair-like nearly black scales, creamy at the sides. Abdominal segments with their terga uniformly sooty except that of the last, which is creamy white ; occasionally the corners of the ventral bands give a deceptive appearance of lateral spots, but they do not really involve the terga.
Head with flat black scales, except the orbits and median and lateral patches on the occiput, which are of an impure white. Antenna of <? three quarters the length of the uniformly sooty proboscis, with almost 25
386 GNATS OR MOSQUITOES — CHAPTER XIII black verticils, those of ? banded. Palpi of J , smooth, black, subulate, its four outer joints subequal, and exceeding the proboscis by the entire length of the end joints ; those of 2 minute, intensely black. Humeral callosities whitish ; scutellum dark in the middle, creamy laterally ; pleursE marbled dark grey and whitish. Halteres with whitish stems and fuscous knobs. Legs sooty, except the undersides of the femora and knees, which are creamy white. Ventral segments black behind, with broad basal white bands pointed at the sides, and easily visible when the insect is viewed from one side. Fore and mid tarsal claws of ? , equal and toothed, of hind simple, those of male, larger and somewhat unequal, but similarly armed (in the ohturhans type they are more unequal). Length. — About 7 mm.
Habitat. — Appears common all along the southern Asiatic littoral from India to China, but I have not met with it inland. Captain James, I. M.S., notes that the larva of this mosquito is large, and has a characteristic whitish woolly appearance. It rests perpendicularly to the surface, and further has very large and characteristic swimming fans. It breeds chiefly in pots and tubs of dirty water, in the open and under trees. It is very rare to find this mosquito in houses, though it is not uncommon in woods.
2. ARMIGERES PANALECTOROS, Sp. n.
Plate xiv, fig. 13, Venation of wing ; 14, Cephalic appendages of 3 ; 15, Tarsal claws of $ ; 16, Decoration of thorax.
Closely resembles the above, but is much smaller, and has the thorax rather elaborately decorated vpith creamy lines, a median broad one, commencing about the middle of the mesothorax, and dividing behind, to turn forward as a pair of lateral lines, which again curve backwards. The scutellum is clothed almost entirely with creamy scales and the tarsal claws of the $ are extremely unsymmetrical, even on the hind legs. Length. — From 3-5 to 4 mm.
Habitat. — Calcutta, during the rains.
Genus XIV. CULEX, Linnaeus.
(Linn. Syst. Nat. (1735), Linnseus ; Fn. Suec. 1890, pi. x, figs. 1—4(1761), LinuEeus; Zweifliig. Ins. i, 1 (1818), Meigen; Gen. Crust, et Ins. iv, 256 (1809), et Hist. Nat. d. Crust, et d. Ins. xii, 284 (1802), Latreille ; Dipt, Exot. 6 (1821), Wiedemann ; Mem. Soc. d'Hist. Nat. de Paris, iii, (1827), Rob. Desvoidy; Hist. Nat. d. Ins. i, 33, 2 (1834), IMacquart ; Dipt. Exot. p. 29 (1838), Macq. ; Ins. Brit. Dipt, iii, p. 243 (1851), Walker; Brit. Ent. xii, 537 (1835), Curtis; Dipt. Scaud. (1850), Zetterstedt; Fn. Austr. ii, (1864), Schiner; Dipt. Near. 323 (1877), Van der Wulp ; Bull. Soc. Ent. Ital. xxvi, 315, et Revis. Sist. d. fam. d.
GENUS CULEX 387 CulicidEe Europ. p. 224 (189G), et Venti Spe. d. Zanzare Ital. p. 98 (1899), Picalbi; Dipt. Arg. p. 57 (1891), Arribalzaga ; Trans. Linn. Soc. . N.S. Wales, p. 1724 (1889), Skuse.)
The Linnsean genus iacladed all gnats having the <? palpi long and those of the ? short, and has of late years come to include an enormous number of species, so that some subdivision is urgently needed.
Even as now, as restricted by Mr. Theobald, it includes some 130 well-defined species (without counting some of the older and inadequately described names), but it is difficult to find any basis for further natural subdivision and for the present we must be content with an artificial classification, based on the coloration of the wings, tarsi, &c. In the restricted genus C. pipiens, L., is made the type species, and its characters may be said to be based on those of that species. Mr. Theobald defines the restricted genus as follows : — Palpi of the 2 short, three or four-jomted; of the <? long, tlireejomted; constrictions at the bases may give the 5 a four or five-jointed and the ^ a five-jointed appearance ; the last joint in the ? is usually large; the male may have the last two joints swollen, much as in Anopheles, or they may be narrower and the last pointed. The antennae, like those of the preceding genera, are pilose in the ? , plumose in the ^ , and are composed of fourteen joints, the last two in the male being long and thin.
Fig. 45. — Venation of wing in Culex.
Head ornamented with narrow curved scales over the occiput, and upright forked scales, especially thick on the back of the head, flat scales on the sides ; thorax with narrow curved hair-like or spindle-shaped scales ; scutellum with narrow curved or spindle-shaped scMes only ; abdomen with flat scales ; wings with small median scales to the veins and more or less thin linear lateral ones to some or all of the veins. In the wings, the first sub-marginal cell is longer and narrower than the second posterior cell, and the posterior cross-vein is always nearer the base of the wing than the mid cross-vein. The scales may collect in certain areas and form spots (C annulatiis), or may be ornamented with spots of differently coloured scales (C niimeticus). The ungues of the 2 are equal, simple or uniserrated, of the <? , vuiequal on the fore and mid legs, the large uni- or biserrated, the smaller uniserrated or simple.
388 GNATS OR MOSQUITOES — CHAPTER XIII Owing to the large number of species to be dealt with it will be more convenient to subdivide its tabulation into a number of groups as follows :— In the first group are included all Culices with spotted wings, whatever may be the decoration of the other parts ; in the second, all the plain-winged Culices with a banded proboscis ; while the remaining groups, including all species with unadorned wings and proboscis, are based on the presence or absence of pale bands on the tarsi, and their exact position when present ; so that, to determine the group to which any species under examination may belong, only three characters need be noted : — viz., those of the wing, proboscis, and tarsi. Each group is further subdivided according to the characters of the abdomen, in addition to which the characters of the thorax should also be carefully noted, before referring to the tables, when identifying an unknown species. The seven groups may be distinguished as follows : — Group I. — With spotted wings (proboscis banded or unhanded). Group II. — With unspotted wings, but with the proboscis banded. Group III. — With wings and proboscis unadorned, but with pale basal bands on the tarsal joints.
Group IV. — As in group III., but with pale bands on the apices of the tarsal joints.
Group V. — As in group III., but with pale bands " on the tarsal articulations," i.e., involving two contiguous joints. Group VI. — As in group III., but with certain tarsal joints wholly white.
Group VII. — As in group III., but witli the tarsi unadorned. Although this is not a natural grouping, it aids very materially in identifying species in this still unwieldy genus. Group I. — Synoptic Tarle of Spotted-Winged Culex. A. Spots along the costa.
Proboscis with a pale band in the middle ; costa black, with yellow spots and apex ; abdominal segments basally yellow banded 1. viliucdcus, Isoe.
Proboscis pale ferruginous, with a broad yellow band in the middle.
Wings with three long mellow and three long black costal spots ; a large species, with apical abdominal bands enlarged in the middle 2. Bigotii, Bellsivdi Proboscis unhanded (?) 3. Hyrca)ius, Pallas.
GENUS CULEX 389 B. Spots on the wing field. iii. Abdomen with basal pale bands ; tarsi banded, a. Thorax not ornamented. Wing spots five ; mid ungues of (^ with larger tooth twice- and smaller oncetoothed 4. aiinidatus, Schrank. Wing spots indistinct, like above species, but mid ungues of ^ both twicetoothed 5, Ficalbii, Noe. 0. Thorax ornamented. Thorax with lines ,of white scales ; wing spots three : legs spotted 6. spathi^alpis, Eondani. Wings with four spots ; forkcells very long 1 . longiareolatus, M&G(iVi&xi. iii. Abdomen with basal pale bands ; tarsi unhanded. Wing spots four or five 8. <jla])liijropterus,^ctimev. iv. Abdomen with apical pale bands.
Wings with a single brown patch near apex 9. /"wtows, Wiedemann. Wings with five spots ; palpi of (^ fihform, not spatulate asin annulatas 10. 2Jendirans, E. Desvoidy. vii. Abdomen with apical triangular pale median spots.
Wings with one spot at base of thhrd long vein 11. Jamaicensis, n. sp. 1. CULEX MIMETICUS, Noe. (Boll. d. See. Ent. Italiana, xxxi, p. 240, Firenze (1899).) Plate XV, fig. 16, Wing of 2 ; 17, Palpi and proboscis of ^ ; 18, Tarsal claws, S' .
Wings with the inner two-fifths of the costa black, followed by two pale yellow interruptions, each about equal to the intervening black portion, and a large pale apical spot ; these spots involve I. and II. and III. are wholly yellow scaled, but the rest are mainly dark scaled ; the internal fringe is dark except
390 GNATS OR MOSQUITOES — CHAPTER XIII a broad yellow patch opposite the anal cell. Tarsi black, with four narrow yellowish bands on the articulations of each leg, commencing with the tibio-tarsal. Thorax dark grounded with greyish-yellow scales, but no obvious ornamentation. Abdomen black with pale yellow basal bands, which are distinctly triangular on the anterior segments. Proboscis spatulate, black, with a narrow but conspicuous yellow band beyond the middle. Head black with ferruginous tomeutum. Palpi of $ black minute ; of $ , one-third longer than the proboscis, subulate, black, with last three joints basally yellow-banded and strongly tufted. The femora are yellow beneath and there are minute knee-spots, but legs elsewhere nearly black. Venter yellow with narrow black apical bands to the segments. Length. — 5 to 6 min.
Hahitat. — First described from Italy. Appears common in the Hills in India, especially in the Nilgiris, and also appears in the plains in the cooler seasons of the year.
2. CULEX BIGOTII, Bellardi.
(Mem. R. Acad. Torino, se. 2, T. xxii, p. 200.)
Plate XV, fig. 6, Wing of ^ ; 7, Wmg of ? ; 8, Cephalic appendages of 5 ; 9, Hmd tarsus ; 10, Antennae, abdominal segments of J^ ; 11, of 5 . Wings with the costa yellow at the base and apex (in the 2 ), with a minute black dot || axillary incision and two large black spots, one in the middle, the other commencing \\ base of anterior fork : II. and V. are mainly black, but the rest of the veins are mainly yellow : or (in the S ) black at the base up to a short white interruption preceding the middle black spot, but the rest of the wing almost entirely pale-scaled; internal fringe pale at base and apex, black elsewhere but for yellow interruptions at each longitudinal junction, and with an extra one inside that of VI. in the $ ; these light interruptions are rather narrow in the $ , very wide in the 3- . Tarsi black with broad yellow bands on the articulations ; last joint of hind pair all yellow, those of other legs less markedly so. Thorax dark-grounded, with a large, ill-defined, cordate black spot. Abdominal segments black, with yellowish apical spots shaped like the " club " of playmg cards ; the hinder segments with additional lateral spots in the $ . Proboscis nearly black with a broad median yellow band, illdefined behind where it shades off into the dark base. Head brown with golden and black scales Palpi brindled Math gold and black scales ; those of ? over one-fourth the length of proboscis, with a sub-terminal yellow dorsal spot ; those of 3 nauch longer than pro-
PLATE XV. an an 26 13 6 14 6 ^^^ isa ?f !^^"?i^. zi# Culices with spotted wings. 1, C. Ficalbii; 2 and 3, ? and S ungues of C. glapMjropterus ; 4, C. longiareolatus ; 5, C. Jamaicensis ; 6 toll, C. Bigotii; 12, Ant. abd. segs. of C. annulatus ; 13, of C. Ficalbii ; 14, J tarsal claws of C. Ficalbii ; 15, of C. annularis ; 16 to 18, C. mimeticus ; 19 to 22, C. annulatus;23to25,C.spathipalpis. Face p.
390.