DESCRIPTIONS OF ALASKAN DIPTERA OF THE FAMILY SYRPHID^. JAMES S. HINE Department of Zoology and Entomology, Ohio State University All of the species treated in this paper except Sericomia cynoctphala were collected by the Katmai Expeditions of the National Geographic Society. Full accounts of the insect collections of these expeditions are being prepared for pubhcation, but as it is desired to refer to some of the species in other papers these descriptions are published in advance of the final report. Chilosia platycera n. sp. Male and female shining black. General form of the body elongate and rather slender. Vestiture of the body mostly pale, scutellum with a marginal row of slender black bristles, eyes naked, antennse yellow, aristce dark, naked; legs largely black, apex of each femur yellow, tibiffl and tarsi partially yellow; wings pale yellowish hyaline. Length 5-7 mm. Female: Eyes bare, face and front shining black, front largely pale pilose, but with a few black hairs intermixed, face below the antennae concave, facial tubercle rather prominent, much nearer the mouth than to the base of the antennae. Antenna wholly yellow, arista dark, nearly black, bare, third segment unusually large, only slightly longer than wide. Thorax wholly shining black with short, pale, pile rather sparsely distributed. Scutellum with a few slender marginal bristles. Wings pale yellowish hyaline, halteres and squamae pale, nearly white; legs in large part black, narrow apex of each femur, base and apex of each tibia and second, third and fourth tarsal segments on all the feet yellow. Abdomen shining black all over, pilosity short and pale grayish in color. Male: Colored like the female, frontal triangle with long black pile, antennae yellow, third segment decidedly smaller than in the female, pilosity of the body rather long and conspicuous, especially along the side margins of the abdomen, abdomen entirely shining, slenderer than in the other sex. Female type, Katmai, Alaska, July, 1917. Allotype with the same data. Paratypes, 12 females and 3 males from the same locahty taken in June and July, 1917, and one female from Savanosky, Naknek Lake, Alaska, July, 1919. Type in the Ohio State University Collection. 143 144 JAMES S. HINE Vol. XXII, No. 5 Chilosia rohusta n. sp. Male and female shining black and conspicuously pale pilose all over. Scutellum without bristles which are differentiated from the rather dense covering of pile. Eyes conspicuously long hairy; antenna yellow, arista dark colored, naked; wing yellowish hyaline, somewhat darker along the costa; legs largely black, tibiae partly yellow. Vesti- ture over the whole body conspicuously pale yellowish in color, occa- sionally varying to golden especially in the female. Form robust. Length 9-12 mm. Female: Front nearly as wide as either eye, shining black, pale pilose; face shining black concave below the antennae, facial tubercle large and located somewhat nearer the oral margin than the base of the antennse. Antenna yellow, first two segments partially brown, third segment about as long as broad. Femora black, yellow at extreme apex of each, tibiae partially yellow, median third or more of each, brown to black, all the tarsi almost wholly dark colored with short golden pile beneath. Wing yellowish hyaline, darkest in costal region of basal half, veins brown, squamae and halteres pale. Male: Colored like the female except the body pile tends toward paler in the specimens studied. Abdomen entirely shining as in the female, and somewhat more slender than in that sex. Differs from lasiopthalma as follows : The face is much less produced in both sexes making the distance between the base of the antennas and the apex of the facial tubercle much shorter than in lasiopthalma, the pilosity of the eyes is paler and shorter and the wings are less infus- cated. Female type, Kodiak, Alaska, June, 1917. Allotype has the same data. Parotypes, five males and ten females with the same data as the type; seven males and fourteen females, Katmai, Alaska, July, 1917; five males and one female. Snug Harbor, Alaska, June, 1919. Type in the Ohio State University Collection. Syrphiis atteyiiiatus n. sp. Male and female. Face yellow, without a black stripe, lower part of front including the insertion of the antennae yellow, antenna largely reddish, third segment dark above, arista dark, eyes naked, occiput dark in ground color but largely hidden by a covering of yellowish gray pollen. Thorax dull blue black in ground color, scutellum rather bright yellow, entire thorax clothed rather densely with long yellow pile, wings hyaline, costal cells opaque' yellowish; "abdomen black 'with three pairs of spots and apex yellow, 'first pair iof spots on Second segment somewhat smaller than the other 'two p3;irs; tri&,ngular, with the long; side anterior, outer angle produced over the, abdominal margin, second pair of spots on the third segmeiit, oblong, 'slightly concave anteriorly and convex posteriorly, outer angle very narrowly produced but scarcely Mar., 1922 alaskan diptera of the family syrphid^ 145 reaching the lateral margin, third pair of spots on the fourth segment similar to those on the third, outer angle produced very narrowly over the margin, posterior margin of fourth segment, anterior and posterior margins of fifth segment and all of sixth segment, yellow. Length, 11 to 13 mm. Female: Front black on the u]jper three-fourths, the lower half of the black color yellowish pollinose, less densely so at middle, front black pilose, pilosity continuing below the antennae on either side next the eyes, much of the face sparsely yellow pilose; all the legs yellow to the bases of the femora, coxas and trochanters dark, posterior feet pale brownish. All the abdominal spots much attenuated and reaching over the abdominal margins, fifth segment yellow with a curved black band about half the width of the segment. Male: Vertical triangle black and black pilose, frontal triangle black on superior half and entirely black pilose, pilosity extending much below the antennas at the sides next the eyes; cheeks blackish beneath the eyes, margin of the mouth behind yellow; legs to the basal fourth of the femora, black, otherwise yellow with the exception of the tibiae which are partially brown, the hind ones nearly black. Fifth abdominal segment yellow with a very narrow median black marking. Genital segment all yellow. Male type taken at Savonosky, Naknek Lake, Alaska, July, 1919. Allotype with the same data. Paratypes, ten males and seven females with the same data, a male from the same locality taken in August and a female from Katmai, Alaska, 1917. In the Ohio State University Collection. The species varies somewhat. In some specimens the abdominal spots are larger and reach the lateral margins plainly and at greater width than in the type. In one specimen the narrow outer margin of the abdomen is all yellow and the black marking on the fifth abdominal segment varies in size and shape in different individuals. Sometimes the hind femora of the male practically entirely yellow. The pair of spots on the fourth abdominal segment is connected occasionally at the anterior inner corners, forming a band which is very deeply notched posteriorly. It is a large robust species, easily separated from others of its size by abdominal markings. Syrphus curtiis n. sp. Male and female: Eyes naked, cheeks, mouth margin and facial stripe extending upward just over the tubercle, black; remainder of face yellow. Antenna largely black, only the inferior margin of the third segment reddish. Thorax yellow pilose, scutellum pale; wings hyaline. Abdomen with three pairs of yellow spots entirely separated from the margins of the segments, posterior margins of fourth and fifth 146 JAMES S. HINE Vol. XXII, No. 5 segments and anterior outer comers of fifth segment also yellow. Length 8-9 millimeters. Female: Front black on upper two-thirds, otherwise yellow with the exception of a narrow crescent shaped mark above each antenna which is dark brown, entirely black pilose. Yellow abdominal spots concave anteriorly and convex posteriorly making them somewhat kidney shaped with the outer anterior corner somewhat produced and pointed ; the spots on the second segment are smaller and more transverse than the others with the inner ends evenly rounded; legs largely yellow, black to the basal fourth or fifth of the front and middle femora and to a greater extent on the hind femora. Hind tibias with dark areas and all the tarsi dark in part. Male: Vertical triangle black, frontal triangle yellow with black pile. Abdominal spots similar to those of the female, but those on the third and fourth segments quite distinctly larger; legs colored similarly to those of the other sex but black of the femora more extensive, including nearl}^ half of middle and front pairs and two-thirds or more of hind pair. Female type, Savanoski, Naknek Lake, Alaska, August, 1919. Allotype with the same data. Parotypes, six males and one female from Savanoski, Naknek Lake, Alaska, 1919, and ten females from Katmai, Alaska, 1917. Type in the Ohio State University Collection. The coloration of the legs is somewhat variable in the species, being darker in general in some specimens, and the black of the femora is more extensive in some specimens than others, especially is this true of the females. The extent of the black on the lower part of the front of the female varies somewhat and the dark crescent-shaped marking above the base of each antenna is more pronounced in some specimens than in others. Syrphiis limatus n. sp. Male and female shining blue black, face with a wide, shining black stripe, wider than the yellow on either side of it, pointed above and reaching nearly to the base of the antennas; cheeks shining black, eyes rather sparsely hairy, antennas black, abdomen with three pairs of narrow spots, first pair small and located near the middle of the second abdominal segment and entirely separated from the margins, second pair near the anterior margin of the third segment very slightly oblique and extending toward the middorsal line but not quite reaching it, inner third of the spot somewhat widened and nearly touching the anterior margin, outer end reaching over the lateral margin in full width; third pair of spots similar to the second, but narrower, located near the anterior margin of the fourth segment; narrow posterior margins of fourth and fifth segments and anterior lateral comers of the fourth segment also yellow. Length 10-11 mm. Mar., 1922 alaskan dipteka of the family syrphid^ 147 Female: Front shinino; black to the base of the antennee, black pilose, with an irregular pollinose band reaching from eye to_ eye above the antennae, this pollinose band is briefly interrupted at its middle. The yellow on each side of the face unites around the upper end of the black middle part and sends a projection up between the antennae. Thorax shining black, scutellum dark brown; wing hyaline, stigma opaque black, space between first and second veins slightly infuscated back to the wing base; legs partly black, outer half of front and middle- femora and apex of hind femur light brown; all tibiae in large part brown, tarsi dark, nearly black. Male: Very near to the female in size and coloration. The hind legs are more extensively black in this sex and the pilosity of the eyes is more pronounced. Type in the Ohio State University Collection. This species is somewhat like creper and paiixillus. It is larger than either and differs in having a much more extensive black marking on the face. The abdominal markings on the third and fourth segments extend over the lateral margins in which respect it agrees with venustus of Europe. Sericomyia cynocephaJa n. sp. Female: Face much produced, so that the distance from the base of the antennae to the apex of the facial production is nearly twice the distance from the base of the antennae to the vertex. Face uniformly yellow, lacking the black stripe commonly present in other members of the genus ; cheeks from the anterior comer of the eye to the apex of the facial production shining black; front black, sparsely gray pollinose and black pilose; antenna black, third segment about as wide as long and very slightly reddish at base, arista black and long plumose; posterior orbits yellowish pilose. Thorax black in ground color, scu- tellum pale brown, whole thorax yellowish pilose; wing hyaline, veins mostly pale, stigma .yellow, squamae pale with a pale fringe, ballancers yellow; legs black, tips of femora, less pronounced on the hind pair, and bases of tibiae yellow. Ground color of abdomen above and below black, segments two, three, and four above each with a pair of oblique elongate yellow spots. All of these spots are widened outwardly and none of them reach any of the margins of their respective segments; spots on the second segment widely interrupted, those on the other segments more narrowly interrupted. Length 14 millimeters. Female type collected by V. Stefansson at Barrow, Alaska, spring of 1912. Type in the American Museum of Natural History. This species is distinct from all the species of Sericomyia known to me by the extreme production of the face and the absence of the black facial stripe. In the other species of the genus^I^have^^ studied the facial tubercle is pronounced, but in cynocephalathis tubercle is only feebly indicated.