66 MISC. PUBLICATION 336, U. S. DEPT. OF AGRICULTURE 
blood or ova.) As shown in the generic key, Aedes and Psorophora 
are distinguished also from the other mosquitoes, except Mansonia 
titillans, by the presence of postspivacular bristles. The Psorophora 
are distinguished from Aedes by having spiracular bristles as well, 
although it is frequently very difficult to see them. In Psorophora, 
however, the dorsal or lateral pale scaling of the abdominal segments 
is apical or diffuse, whereas in Aedes it 1s generally basal or extends 
from the base. In Psorophora, subgenus Grabhamia, the femora and 
tibiae are speckled, and at least the hind femur has a narrow white 
ring near the apex. In subgenera Psorophora and Janthinosoma the 
mesonotum is partially or completed covered with broad, flat scales, 
and some of the leg scales frequently are erect. The subgeneric 
divisions of Aedes are not easily defined on markings, and these ¢ eroup- 
ings have not been included. The subgenera of Culex have been 
referred to in the discussion of that genus. 
Difficulties may arise from the separation of the species of Wyeo- 
myia on the pale tarsal markings, as these are easily overlooked. 
The species are of extremely limited distribution, however, and are 
rarely collected. The positive means of identification of the genus 
is by the presence of postnotal bristles. 
Keys To ADULTS 
All the known southeastern species are included in the first key. 
Following this is a short key to the male terminalic characters of the 
dark- legged Culex and then a separate key giving a synopsis of gen- 
eric characters. 
SPECIES KEY 
In the species key the characters apply primarily to the female, 
unless the male is mentioned. Although the markings of the male are 
generally similar to those of the female and the males of most species 
can be identified by the characters given, some differences occur in 
the distribution of the pale scales. The white bands on the abdominal 
segments, for example, cannot be used satisfactorily in identifying 
the males of the subgenus Culex. This key is preceded by a synopsis 
of the principal divisions. 
Mosquitoes" having lone jpalpi in both) sexess 2 2s eee eee Couplet 2 
Genus Anopheles ses SO SS I a NE a a ne 2 
Mosquitoes having a rigid proboscis, down- curvy “ed on outer half; very large, 
iridescent species___-________ eevee ranean Se re ead ee 10 
Genus Megarhinus__________- oe Ee Shi 2 ee ee 10 
Mosquitoes having the second marginal cell very short; very small species 
having iridescent thoracic markings ase = rR ed OFS 3: 12 
Genus * Unranotaenia. 22" 2 es ee DD, 
Mosquitoes without tarsal or mesonotal ‘markings Sf gs LT SS 14 
Genus: Deimocerités 2 ee ee eee 14 
Genus Psorophora (P. cyanescens) ; Aedes (A. cinereus)_____________ 16 
Genus Culex (except C. bahamensis and C. tarsalis) ; Theobaldia______ aT 
Mosquitoes with tarsal or mesonotal markings, or both_____________________ 26 
Large species, with long, erect scales on femora and tibiae; the galli- 
NIPPCUS 2222 ee ee es Ce aed es gia. a ie See mate 
Genus PLsorophora ((Esorophore) = 2 2-3 e Soo 
Bright yellow species tee Sc SL ae SERS 
Genus Aedes (A. fulvus pallens) _ eee Mee A ree SC ERE es SS aes 
ee lal 
