248 
nymphs have indicated that the species 
separate into two fundamentally different 
groups. [hese two groups were recognized 
in my studies of the Illinois species (1929, 
1935a) as the genera T'aentopteryx Pictet 
(1841) (= Nephelopteryx Klapalek 
1902) and Strophopteryx Frison (1929). 
Beginning with Klapalek, in 1902, numer- 
ous generic names have been proposed for 
the reception of various species in this 
family. Since the world species break up 
into many small units, and each new spe- 
cies seems to present a new combination of 
the characters used as the basis for these 
genera, I am_ following the course, at 
least for the present, of accepting these 
names as subgenera and holding to a gener- 
‘c division which presents more marked or 
fundamental differences in the nymphs as 
well as adults. 
The name of Taeniopteryx Pictet 
(1841) with its genotype of nebulosa 
(Linnaeus), as used by me in 1929, still 
holds for one of these basic genera, and 
the name Brachyptera Newport (1851) 
with its genotype of trifasctata (Pictet) is 
the first name available for the other. 
Strophopteryx Frison (1929) belongs as 
one of the subgenera of Brachyptera. In 
T aeniopteryx belong the species like maura 
(Pictet), which have nymphs with coxal 
gills, adult males with one-segmented cerci 
and a ninth abdominal sternite reaching 
only to tip of abdomen, and adult females 
with the subgenital plate poorly developed. 
In Brachyptera belong the species like 
fasciata (Burmeister), which have nymphs 
lacking coxal gills, adult males with sev- 
eral-segmented cerci and a ninth abdom- 
‘nal sternite recurved up about the tip of 
the abdomen, and adult females with the 
subgenital plate much produced. 
KEY TO GENERA 
OF TAENIOPTERYGIDAE 
ADULTS 
Males with one-segmented anal cerci, ninth 
abdominal sternite reaching only to tip 
of abdomen and not abruptly recurved 
upwards about tip of abdomen, forewings 
always normal; females with subgenital 
plate not or scarcely produced ; both sexes 
show coxal gill scars......... Taeniopteryx 
Males with several-segmented anal cerci, 
ninth abdominal sternite abruptly curved 
up about tip of the abdomen, forewings 
sometimes brachypterous; females with a 
well-developed and protruding subgenital 
plate; both sexes without traces of coxal 
pillisscans Sue Shenae ante eens oe: Brachyptera 
Intinois NATURAL HIsToRY SurvEY BULLETIN 
Vol. 22, Arg 
NYMPHS 
Coxal gills present and terminal abdominal 
structures suggestive of characters of 
adults «: 2 << :.0.0% 795s ... Taeniopteryx 
Coxal gills absent and terminal abdominal 
structures suggestive of characters of 
adults ~~. f2.50 oe ee Brachyptera 
Taeniopteryx maura (Pictet) 
Nemoura maura Pictet (1841, p. 361). Orig- 
inal description, 9. 
Nemoura nivalis Fitch (1847, p. 274). New 
synonymy. 
Taeniopteryx nivalis Frison (1929 and 
1935a, pp. 378 and 341, respectively). Descrip- 
tions and records. 
In my paper of 1929 I stated that “it is 
likely nivalis and maura are the same spe- 
cies,” and, again, in 1935 that “there is a 
strong probability that maura (Pictet) 
and nivalis (Fitch) are the same species 
_ in which case the former name would 
have priority.” 
Since these earlier papers I have had 
‘occasion to determine many hundreds of 
specimens from all parts of the distribu- 
tional range of nivalis and maura, and | 
have come to the definite conclusion that 
nivalis should be regarded as a synonym 
of maura. In the past, maura and nivalis 
have been separable in the males only, and 
then on the basis of the presence or ab- 
sence of a toothlike projection on the lowe1 
surface of each femur. As first pointed 
out in 1929, I find in the males from the 
same locality that some have this toothlik 
projection and others do not; in fact, speci 
mens are not uncommon which have thi 
tooth on one femur and lack it on thi 
other. Another structural character 0 
maura displaying great variation in siz! 
and shape is the lobe near the base of th 
ninth abdominal sternite. Coupled witl 
the facts that two species of females can 
not be detected and that differences 1 
other characters known to be of grea 
specific importance (such as_ the cerc 
supra-anal process and subanal lobes) can 
not be found, it no longer seems tenabl 
to recognize maura and nivalis as tw 
distinct species. 
Whether the name of maura is bein 
correctly used can never be definitel 
settled because, as Ricker (1938) record: 
only parts of the type remain, and they at 
not the parts most needed to make a 
curate determinations of species belongin 
to this family. No specimens of the typ’ 
