Vol. 5, p. 101-106. July 2, 1924. 



Occasional Papers 



OF THE 



Boston Society of Natural History. 



NEW SPECIES OF THE DIPTEROUS FAMILY 

 DOLICHOPODIDAE. 



BY MILLARD C. VAN DUZEE. 



In identifying specimens of the family Dolichopodidae sent 

 from New England and elsewhere, several new species have been 

 recognized, the descriptions of which are here given. 



Thinophilus ochrifacies, new species. 



cT. — Length 2-2.7 mm. Face wide, ochre yellow. Palpi yellowish with 

 thick yellow pollen, still they are more whitish on apical edge. Front blue or 

 green on the vertex, sometimes wholly opaque with yellowish pollen. Occiput 

 covered with j^ellowish pollen, its lower half with long white hairs; upper 

 orbital cilia black. Antennae yellow; third joint brown, small; arista brown. 



Dorsum of thorax and the abdomen greenish, the former with thick brown 

 pollen; pleurae and coxae more black with white pollen. Abdomen with 

 conspicuous black hairs. Hypopygium small, with yellow appendages extend- 

 ing forward under the abdomen (I think there are also brown appendages folded 

 up close to the venter above the yellow ones). 



Fore coxae more or less yellow, but greenish or brown at base, sometimes 

 mostly infuscated; they are nearly bare. All femora and tibiae yellow. 

 Middle tibiae with one small bristle above near the base and another near the 

 middle; posterior pair with several small bristles. Tarsi yellow at base, 

 usually brown toward their tips; joints of fore tarsi as 15-7-7-5-5; middle ones 

 as 22-10-9-6-7; joints of hind pair as 14-16-10-7-8. Pulvilli very small, 

 whitish. Calypters, their cilia and the halteres yellow. 



Wings grayish, sometimes tinged with brown in front, without any trace 

 of clouds on the cross-vein or last section of fourth vein; last section of fifth 

 vein and cross-vein about as 26 to 8. 



9 . — The face is about the same as in the male, still it appears more 

 brown, it is wholly opaque with pollen; the palpi are longer than in the male 

 and have the pollen more white. The general color is about the same, as is 

 also the proportionate length of the tarsal joints; wings as in the male. 



Described from four males and seven females. Two males and 

 a female were taken at Cold Spring Harbor, Long Island, New 

 York, September 5, by Mr. Burns; all the rest were taken by 

 C. W. Johnson in Massachusetts: one male (holotype) at Cohas- 

 set, September 8; one male at Edgartown, June 29; two females 

 at Chatham, July 1 ; and four females at Eastham, June 27. 



Holotype and allotype in the collection of the Boston Society 

 of Natural History. 



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