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UNITED STATES NATIONAL MUSEUM BULLETIN 2 24 



the alula is large, the ambient vein distinctly ends at 

 the anal cell. 



Abdomen: The abdomen is robust and short, but 

 rather strongly tapered from the base, which is fully as 

 wide as the mesonotum ; the middle of the tergites are 

 slightly flattened. In the female are eight tergites; the 

 eighth is about two-thirds as long as the seventh, the 

 seventh not more than half as long as the sixth, and the 

 sixth about three-fourths as long as the fifth. Sides of 

 the first tergite with 7 or 8 distinct bristles in a double 

 row, remaining tergites with only bristly hairs 

 laterally. The pile of the abdomen is quite scanty, flat 

 appressed and setate. The tergites may have inter- 

 rupted, lateral fascia of minute scales. Female ter- 

 minalia with at least 4 pairs of long, apically rounded, 

 more or less spatulate spoon-shaped spines. No males 

 were seen. 



Distribution : Palaearctic : Amphisbetetus affinis Her- 

 mann (1906) ; dorsatus Becker in Becker and Stein 

 (1913); favillaceus Loew (1856); gederati Efflatoun 

 (1937). 



Genus Iranopogon Timon-David 



Figures 2512, 2513, 2519 



Iranopoyon Timon-David, Bull. Soc. Ent. France, vol. 60, p. 103. 

 1955. Type of genus: Iranopogon brandti Timon-David 

 1955, by original designation. 



I give below Timon-David's description in 

 translation : 



Related to Amphisbetetus Hermann. Iranopogon is situated 

 among the Dasypogoninae Eremocnemini of Hermann. Length 

 9.5 mm. 



Size average; pile but little developed. Head very large, 

 much larger than the thorax, concave in the posterior part. 

 Width of the front at the level of the ocellar tubercle a little 

 inferior to half of the width of the eye. Front at the sides 

 parallel. Face at the sides strongly divergent toward the bot- 

 tom. Proboscis very short. Antennae inserted at the level of 

 the middle of the eye. Style Particulate, with a short, sensory 

 spine at the tip. No spur on anterior tibia. Wing: marginal 

 cell open ; anal cell closed and petiolate. All posterior cells 

 open. Ovipositor (oviscapte) without spines. 



The nearest relative of Iranopogon seems to be Amphisbete- 

 tus Hermann, 1906, but there are these important differences; 

 in Amphisbetetus the internal border of the eyes in the region 

 where they delimit the face are subparallel and not strongly 

 divergent (see fig. 262, p. 420, given by O. Engel in Lindner) ; 

 the eyes are less developed in the transverse sense, the probos- 

 cis is much longer, the anal cell is closed in the margin and 

 not petiolate; the ovipositor is armed with spines. With 

 Pycnopogon Loew, the frontal area is considerably enlarged to- 

 ward the vertex ; with Eabropogon Loew, the contraction of the 

 first and second metatarsi is characteristic. With Stichopogon 

 Loew, the frontal area is much enlarged at the upper part and 

 the abdomen is compressed dorsoventrally. With Crobiloeerus 

 Loew, the style is ciliate, the proboscis strong and long. With 

 Anisopogon Loew and with Heteropogon Loew, the insertion 

 of the antennae is made above the middle of the eye and the 

 ovipositor is always armed with spines. 



Distribution: Palaearctic: Iranopogon brandti 

 Timon-David (1955). 



In the females of some genera, like Amphisbetetus 

 Hermann, the ovipositoral spines are not only minute 



but often deeply recessed and inconspicuous. If 

 Iranopogon truly lacks spines, this is a character of 

 great interest, and one that possibly additional speci- 

 mens will be needed to verify. 



Genus Astylopogon de Meijere 



Figures 2520, 2532 



Astylopogon de Meijere, Bijdragen tot de Dierkunde, vol. 19, p. 

 51, 1913. Type of genus: Astylopogon catharinae de Mei- 

 jere, 1913, by monotypy. 



I give below a translation of de Meijere's description : 



Related to Dioctria in form. Length 5 mm., length of wing 

 4 mm. 



Head short. Eyes large, the anterior facets considerably 

 larger. Ocellar bristles very short and weak. Third antennal 

 segment of elongate form, longer than both basal segments to- 

 gether, and before the apex with a thorn or spine situated dor- 

 sally; a style is not present. Lower face narrow, of equal 

 breadth, and without a gibbosity. The epistomal mystax or 

 beard is composed of only small, or weak bristles. Proboscis 

 short, held horizontally. Thorax as long as broad, without 

 bristles, strongly arched. Metapleuron with long bristles. 

 Scutellum without bristles. 



Abdomen of slender form. Legs not especially long. Ante- 

 rior tibia at the apex without bristle, only with a little hair. 

 Femora and tibiae with many bristly hairs. Hind femur and 

 hind tibia at least in the type of genus with a brush of hair. All 

 metatarsi clearly somewhat longer than the following segment. 

 Pulvilli well developed. Wings, moderately broad ; the first 

 longitudinal vein ends on the anterior wing margin relatively 

 close to the auxiliary vein. The discal cell sends only two 

 veins to the wing margin, so that there are only four posterior 

 cells, all of which are open. Also the third posterior cell is 

 not narrowed on the wing margin, and the base is not stalked. 

 Second discoidal cell and fourth posterior cell provided with a 

 short crossvein at base. Anal cell closed. Alula rudimentary. 



Distribution : Australian : Astylopogon catharinae 

 de Meijere (1913) . (From Waigeu) . 



Genus Oligopogon Loew 



Figures 69, 461, 1107, 1116, 1881 



Oligopogon Loew, Linnaea Entomologica, vol. 2, p. 497, 1847. 

 Type of genus: Dasypogon hybotinus Loew, 1847, by 



monotypy. 



Small, delicate flies with slender, more or less flattened 

 abdomen, densely pale pollinose and with short scanty 

 pile. They are readily recognized by the presence of 

 long plumes on the outer half of the third antennal 

 segment. This segment is strongly attenuate and car- 

 ries a plumose style as long as the remainder of the 

 segment. The eyes are very wide and flattened with 

 greatly enlarged central facets and from a dorsal view 

 strongly excavated posteromedially. From the Dam- 

 alini, which it otherwise resembles, it is separated by 

 the presence of 4 pairs of long, rather sharp, well 

 developed spines on the female acanthophorites. Length 

 6 to 7 mm. 



Head, lateral aspect: The face is exceptionally short 

 and very little produced ; it is chiefly visible because of 

 the posterior recession of the eye and is gently rounded, 



