298 



NORTH AMERICAN DIPTERA 



Family Lonchseidse 



Small shining blackish flies, the auxiliary vein entire; the tibia; 

 without preapical bristles. 



Head shorter than high; face and front moderately wide; oral 

 vibrissa; absent; front with a single orbital, clothed with short hairs; 

 ocellars present; postocellars divergent; antennte elongate, decumbent. 

 Thorax bristled posteriorly; mesopleura with bristles behind; one or 

 two sternopleurals; propleural present, the propleura without hair. 

 Legs short; tibia? without preapical bristle. Wing venation complete; 

 second basal and anal cells short, the anal vein reaching the wing 

 margin faintly, and bisinuate. Abdomen oval, rather flat; ovipositor 

 rather long and triangular. 



The adults occur almost everywhere but prefer moist or shady 

 places. The larva- live in plants or decaying vegetation. They have 

 been reared from under bark and may be predaceous. 



This family is readily distinguished from the Periscelida' by its 

 entire auxiliary vein; from the Sa]n-omyzida^ by the absence of pre- 

 apical tibial bristles on at least the anterior and posterior tibia^ and 

 from the Pallopteridaj by the i)resence of a propleural bristle and the 

 exposed frontal lunule. 



Lonchcea Fallen is the only genus recognized although Earomyia 

 Zetterstedt may be distinguished by having the frontal lunule bare. 

 Malloeh* has reviewed the species. A few have been described since the 

 publication of his paper. 



* 1924. Pioc. U. S. N. M., Ixv, Art. 12, w. 3-6. 



Lonchsea, head, wins and abdomen. 



