114 
DIPTERA 
63. Genus DYNATOSOMA, Winnertz 
Dynatosoma. Winnertz, Verh. Zool.-bot. Ges. Wien, Vol. i3, p. 947 (41) (i863). 
Characters. — Head oval, flattened in front, placed low upon the thorax; front broad, the 
anterior margin not produced into a triangle, vertex high; e5'es oval; ocelli usually two in number, 
large; the middle one, when present, very small; antennae arcuate, 2 -f- 14 jointed; the basal joints 
differentiated, setose at the tip, the flagellar joints c^dindrical, only slightly compressed, pubescent. 
Palpi incurved, the first joint small, the fourth longest. Thorax oval, highl}' arched, pubescent, at the 
lateral margins and over the fore coxae with longer hairs, hind margin setose; scutellum semicircular, 
margin setose; metanotum steep, somewhat arched. Abdomen of the male six segmented, forceps 
moderate (PI. 7, Fig. 19); of the female with seven segments, compressed, constricted at the base, 
ovipositor with two small lamellae. Legs strong, femora compressed, tibiae with spurs, the fore and 
middle pairs with a few setas on flexor and extensor surfaces, hind pair with three ranges of stout, long 
setae on the extensor surface and a range of weaker ones or with one or two stout setae on the flexor 
surface; plantae of hind tarsi ciliate with fine setulae. Wings longer than the abdomen, oval, with rounded 
base, surface covered with closely spaced longitudinal rows of microscopic setulae. Costa does not extend 
beyond the tip of the radial sector; subcosta about half as long as the basal cell R, and ends in R, ; media 
forks under or distad of the base of the radial sector; cubitus forks under or distad of the base of the 
media, its branches widely divergent; first anal vein long but incomplete, strong; second anal vein 
short (PI. 6, Fig. 25). 
This genus is readily distinguish from other forms with two ocelli by the course of the subcosta; 
when rarely there are three ocelli present, the form of the subcosta together with the strong tibial lateral 
setae will separate it. 
Type species : D. /iiscicorue, ]\Ieigen. 
Geographical distribution of species : 
D. cochleare, Strobl, Mitth. Naturvv. Ver. Steiermark, 1894, p. 181 (1895). 
D. crassicornis, Meunier, see Syiiplasia. 
D. fulvidiitn, Coquillett, The Canad. Entom. Vol. 27, p. 200 (iSgS). 
D. fiiscicorne, Meigen, Syst. Beschr. Vol. i, p. 261 (2) (1818); Vol. 6, 
p. 297 {Mycetophild) (i83o). 
fuscicorne, Zetterstedt, Dipt. Scand. Vol. 1 1, p. 4194 (17) {Mycelopliila} (i852); 
Winnertz, Verh. Zool.-bot. Ges. Wien, Vol. i3, p. 948 (i) (i863); 
Schiner, Fauna Austr. Dipt. Vol. 2, p. 492 (1864); Van der Wulp, 
Dipt. Neerland. Vol. i. p. i58, pi. 5, f. 10 (1877). 
pyaeustum, Meigen, Syst. Beschr. Vol. 6, p. 298 (3i) [Mycetophild) (i83o). 
D. gracilis. Kertesz, Term. Filzet. p. 24 (4o3) (1901). 
D. inaeqiiale, Strobl, Verh. u. Mitth. Siebenb.Ver. f. Naturw. Hermann- 
stadt, 1896, p. i3 (1897). 
D. lutescens, Zetterstedt, Dipt. Scand. Vol. 11, p. 417S (3) [Mycetophila) 
(i852j. 
D. mediastinalis, Lundstrom, Acta Soc. Fauna Flor. Fenn. p. 29(1, 19) 
[Rhymosia) (1907). 
D. nigricoxa, Zetterstedt, Dipt. Scand. Vol. 11, p. 4187 (10) [Myceto- 
phila) (i852). 
«/^t-/iroAr(r, Winnertz, Verh. Zool.-bot. Ges. Wien, Vol. i3, p. 949 (2) (i863); 
Schiner, Fauna Austr. Dipt. Vol 2. p. 492 (1864). 
D. iiobile, Loew, Berl. Ent. Zeitschr. Vol. 18, p. 35 (9) (1S73), 
D.prncusiiim, M.e\gen = fuscicorne, Meigen. 
Central Europe. 
Western United States. 
Europe. 
Peru. 
Central Europe. 
North Europe. 
F'inland. 
Europe. 
Central Europe. 
