ANNALS 



OF 



The Entomological Society of America 



Volume XI DECEMBER, 19 18 Number 4 



A REVISION OF THE GENUS SCIARA OF THE FAMILY 

 MYCETOPHILIDi(E (Diptera) 



By F. W. Pettey, Cornell University. 



In working over the Cornell University collection of spec- 

 imens of Sciara, family Mycetophilidae, thirty-one new species 

 collected in the United States were discovered. Consequently 

 it was thought advisable to revise Dr. Johannsen's Sciara key, 

 found in the Maine Agricultural Exp. Sta. Bull. No. 200, 

 Part IV, pp. 117-123. The work was done under Dr. 

 Johannsen's direction. 



Dr. Johannsen, in his classification of the species of the 

 genus Sciara, has divided them into two main groups, those 

 whose wings have setose media and cubitus and those whose 

 wings have no setae on these veins. Other scientists, in their 

 description of new species of Sciara, have frequently overlooked 

 this important structural character. In an effort to call more 

 particular attention to this feature and to avoid the possibility 

 of neglecting it in the future descriptions, a new genus is pro- 

 posed for those species having no set£e on the media and cubitus. 

 Since the type species of the genus Sciara, thomce, L. (Syst. Nat. 

 Ed. XII, II. 976.39 (Tipula) 1767), has subsequently been 

 found to have setose media and cubitus, those species having 

 this character are left in the genus Sciara. 



About half of those species of the male sex under the new 

 genus have a hypopygium with one or two clusters of setae at 

 the base on the median ventral line. No males of the genus 

 Sciara as above restricted exhibit this character. Although this 

 structure should not be overlooked in the description of a 

 species, it would be inadvisable to make use of it as a generic 

 character, since it cannot be designated in females. 



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