Caddisflies of the Yukon - Department of Biological Sciences ...

812 G.B. Wiggins and C.R. Parker
FIGS. 2 – 3. 2, Rhyacophila mongolica Schmid, Arefina and Levanidova (14) (Rhyacophilidae), male genitalia: a,
lateral; b, segment X, caudal (YT: ROME 810565); 3, Rhyacophila sibirica McLachlan, segment X, caudal (Russia,
Siberia: ROME).
et al. 1993); our material has been compared with specimens provided by these authors from
Russia. This is the first North American record for this species, otherwise widely distributed
in the Russian Far East and Mongolia. The pharate male differs from its sister species R.
sibirica McLachlan in details of segment X (cf. Figs. 2b, 3).
Note 2. Goera tungusensis Martynov (47)
Goera radissonica Harper and Méthot 1975, new synonymy
During this study, we found that Goera radissonica Harper and Méthot (1975) from
northern Quebec is a junior subjective synonym of Goera tungusensis Martynov (1909) from
Siberia, confirmed through comparison by W.K. Gall of the holotype male of G. radissonica
with specimens of G. tungusensis obtained from the Zoological Institute, St. Petersburg.
Note 3. Ceraclea nigronervosa (Retzius) (56)
We found 2 forms of adults of this species in the Yukon and Beringian collections
studied. In both forms the dark veins of the forewing contrast strongly against the membrane,
but the wing membrane is reddish brown in one and gray to colourless in the other. The
gray-winged form is inferred to be typical for the species, in accordance with McLachlan’s
(1877) description which applies to specimens from northern and central Europe; we have
similar material from Finland. However, the brown-winged form shows several distinctive
characters in the male genitalia as described below.
Male genitalia (brown-winged form, Fig. 4). Segment IX in ventral view approximately
twice as wide as long (width less than twice length in gray-winged form, Fig. 6); basal
segment of inferior appendages extended into a prominent posteroventral process (little
extended in gray-winged form). Segment X with superior appendages long and tapered
apically (shorter and not tapered in gray-winged form); segment X with each ventrolateral
lobe bearing short stout setae basally (stout setae lacking in gray-winged form). Phallus with
apical membranous endotheca spherical in caudal view (less expanded in gray-winged form).
Female genitalia. The female genitalic structure is variable and no characters concordant
with the males were found; characters illustrated for each form (Figs. 5, 7) can occur in both