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UNITED STATES NATIONAL MUSEUM BULLETIN 2 24 



TART 1 



pile. Males with eight segments, the eighth about half 

 as long as the seventh and all segments slightly and 

 progressively reduced in length; sometimes the last 

 three segments are more conspicuously reduced. Fe- 

 males with eight segments, the eighth segment reduced 

 and the character of the pile tends to be altered on the 

 last three segments and greatly reduced. Males with 

 the terminalia not rotate, the epandrium polished, 

 characteristically turned downward into a blunt, pos- 

 teriorly obtuse, or flattened structure and not cleft, al- 

 though there may be a very shallow, posterior sulcus 

 and a roughened medial area. Proctiger large with 

 medial groove and apical notch and likewise turned 

 downward. Hypandrium moderately long, laterally 

 expanded at base, obtuse on either side of the apes and 

 with considerable stiff pile. Gonopod well developed 

 from the lateral aspect with a slender, ventral process 

 and a wider, dorsal, more obtuse, thin process. Female 

 with acanthophorites and 5 pairs of obtuse, spoonlike 

 spines. 



Heteropogon is an Holarctic genus of medium size. 

 I have not seen the two species described from South 

 Africa and cannot comment on them. 



Distribution: Nearctic: Heteropogon arizonensis 

 Wilcox (1941) ; cirrhatus Osten Sacken (1877) ; currani 

 Pritchard (1935); duncani "Wilcox (1941); johnsoni 

 Back (1904) ; lautus Loew (1872) ; ludius Coquillett 

 (1893) ; macerinus Walker (1849) [=gibbus Loew 

 (1866)] ; maculinervis James (1937) ; patruelis Coquil- 

 lett (1893) ; paurosomus Pritchard (1935) ; phoeni- 

 curus Loew (1873); rubidus Coquillett (1893); 

 rubrifasciatiis Bromley (1931) ; senilis Bigot (1878) ; 

 spntulatus Pritchard (1935) ; vespoides Bigot (1878) ; 

 wilcoxi James (1934). 



Neotropical: Heteropogon eburneus "Walker (1849) ; 

 phalma Walker (1849) ; rejeetus Williston (1901). 



Palaearctic: Heteropogon alter Becker (1915); au- 

 rocinctus Seguy (1934) ; aureus Becker (1907) [=albi- 

 barbatus Becker (1915)] ; biplex Becker in Becker and 

 Stein (1913) ; elegans Becker (1907) ; erinaceus Loew 

 (1870) ; flicornis Loew (1870) ; flavobarbatus Becker 

 (1907) ; glabellus Roeder (1881) ; [ = curviventris Mik 

 (1882)]; hermanni Engel (1930) [^glabellas Her- 

 mann (1905) not Roeder] ; lugubiis Hermann (1905) ; 

 manicatus Meigen (1820) ; manni Loew (1954) ; nubilis 

 Wiedemann in Meigen (1820) [ = brevis Schiner 

 (186S)]; ornatipes Loew (1851); parvum Efflatoun 

 (1937) ; pxdehrum Efflatoun (1937) ; pyrinus Hermann 

 (l905) ; rubiginipennis Macquart (1849) ; scoparius 

 Loew (1847) ; succinctus Loew (1847) ; wdltlii Meigen 

 (1820). 



Ethiopian: Heteropogon gracilis Engel and Cuth- 

 bertson (1937) ; peregrinus Engel (1929). 



Country unknown: Heteropogon aegon Walker 

 (1849) ; anemetus Walker (1849) ; cerretanus Walker 

 (1849); copreus Walker (1849); potitus Walker 

 (1849) isilanus Walker (1849). 



See Rieardo (1912, p. 160) for her comments on these 

 Walker species placed by Kertesz in the genus 

 Heteropogon. 



Subgenus Anisopogon Loew 



Anisopogon Loew, Berliner Ent. Zeitschr., vol. 18, p. 377, 1874. 

 Type of subgenus: Anisopogon glabellus Roeder, 1881. 

 Designated by Efflatoun, 1937. 



While Engel (1930) considered the separation of 

 Anisopogon from Heteropogon Loew untenable, Effla- 

 toun has adopted the name as a useful basis for the 

 separation of those species of Heteropogon, which are 

 small, with the narrow, flat face bearing a sparse, 

 weak mystax of soft hairs and at most 2 or 3 weak 

 bristles or bristly hairs in the center. Style of third 

 antennal segment much shorter than the third seg- 

 ment and less pointed. The position of the head is 

 less ventral, the thorax relatively smaller, and the 

 abdomen narrower and with longer, softer pile. Ven- 

 tral proctiger of female long and boat-shaped. Effla- 

 toun (1937) states that there are no spinelike proc- 

 esses at the apex of the terminalia but he has certainly 

 had in mind the two Egyptian species which he de- 

 scribed. Engel (1930) would restrict the name A niso- 

 pogon on the characteristics of the terminalia and ovi- 

 positor and would include in it only Anisopogon 

 hermanni Engel and glabellus Roeder. 



The following species have been assigned by dip- 

 terists to this subgenus: Anisopogon hermanni Engel, 

 erinaceus Loew, wdltlii Meigen, rubiginipennis Mac- 

 quart and particularly parvum, Efflatoun, pulchrum 

 Efflatoun and the type of this subgenus, which is 

 glabellus Roeder. 



Genus Mecynopus Engel 



Figures 112, 515, 1036, 1045, 1931 



Mecynopus Engel, Konowia, vol. 4, p. 191, 1925. Type of 

 genus: Mecynopus pulverulentus Engel, 1925, by original 

 designation. 



Small, slender flies with a rounded face which bears 

 numerous, long, weak bristles or bristly hairs. These 

 flies are related to the Nearctic genus Metapogon 

 Coquillett and are separated by the reduced or absent 

 pulvilli. Length 8 to 10 mm. 



Head, lateral aspect: The head is moderately long, 

 strongly convex anteriorly, and narrowed below. The 

 occiput is unusually prominent and obliterated only 

 at the immediate dorsal aspect of the head. The oc- 

 cipital pile is long, dense and fine. Upper occiput 

 with 9 white bristles on each side, replaced by yellow- 

 ish white pile at the upper eye corner. The proboscis 

 is short, slightly compressed laterally, with the apex 

 bluntly rounded and pilose; the base bears long pile 

 ventrally. It is directed obliquely downward. The 

 antenna is attached at the upper third of the head 

 and is relatively slender. Its length, microsegment 

 included, is a little greater than the length of the head. 

 First and second segments of equal length, each longer 

 than high and bearing quite long, stiff, bristly hairs 

 below and above, other hairs only a little shorter. The 

 third segment is at least as long as the first two com- 



