No. 64] 



DIPTERA OF CONNECTICUT: TAXONOMY 



295 



Liogma Osten Sacken 

 18C9. L'/ogma Osten Sacken; Mon. Dipt. X. Aniei'.. 4:298. 



A very restricted gronp (seven species), widespread throughout 

 the Holarctic Region. The polished black coloration of our local 

 species, in conjunction with the strongh^ nodulose antennae, renders 

 the fly conspicuous and easily recognizable. The adults are common 

 in deep shaded woods. The larvae feed on terrestrial mosses. 



Key to Subspecies 



1. Mesonotum and pleura chiefly polished hlack, the dorso-pleural membrane 



yellow nodicornis nodicornis 



Posterior sclerites of mesonotum and most of thoracic pleura yellow 



nodicornis flaveola 



2nd A 



Figure 2)2). Cylindrotominae. 

 A. Phalocrocera tipulina O.S. ; anten- D. Triogma cxculpta OS.; auimna, $, 



na, $, basal segments. t)fs^ ^"<^ ^P^-"^- 



T, ^ r ^ * t I- 1 u . ^u^ E. Plialacroccra nco.rcna Alex. : wmg. 



r5. Lyhnarotoma tarsalis Johns. the „ „ ^.^ ,. ^^ r- ■ „ 



-^ F. P. hpuliiia O.S. ; wmg. 



^^^^- G. Cvliiidrotoma tarsalis Johns. ; wing. 



C. Liogma nodicornis (O.S.) ; antenna, h. Lioginu nodicornis (O.S.) ; wing. 



$. I. Tri'ogma e.vcnlpta O.S. ; wing. 



Symbols: a, antenna; A, Anal; Cit, Cubitus; M, Media; R, Radius; Sc. Subcosta. 



Liogma nodicornis nodicornis (O. S.) (Fig. 33, C, H). 

 1865. Triogma nodicornis Osten Sacken; Proc. Ent. Soc. Philadel- 

 phia, 4:239. 



Figs.— Osten Sacken, Mon. Dipt. N. Amer., 4, pi. 1, fig. 7 (wing) ; 1869. 

 Needham, 23rd Rept. N. Y. St. Ent. for 1907, pi. 15. fig. 5 (ven.) ; 1908. Alexander. 

 Cfls. N. Y., 1:850, text-fig. 125, I (ant. 6 ). pl. 30, fig. 5 (wing) ; 1919. Ale.vander, 

 Gen. Ins.. Fasc. 187, pl. 1, fig. 1 (entire insect), 6 (ant. $): pl. 2, fig. 9 (wing); 

 1927. Dickinson. Cfls. Wise. p. 210. fig. Ill (wing); 1932. 



