Molanna byssa, Arefina, Tatyana I., 2005

Arefina, Tatyana I., 2005, Two new species and new records of caddisflies (Insecta: Trichoptera) from the Far East of Russia, Zootaxa 1088, pp. 45-53 : 48-49

Molanna byssa , new species

Figs 2 , 3

Holotype male. RUSSIA: Amurskaya Oblast: Byssa River at Fevralsk Town (Amur River Basin), 15.vi.2004, T.I. Arefina.

Paratype. Same data as holotype, 1 male.

Adult. Length of fore wing: male 11.4 mm. Head and thorax dark brown, antennae, legs and abdomen lighter. Forewing brownish, hind wing paler, both covered with short dark hair all over membrane; venation as in Fig. 2 . Hind wing with row of small hamuli on front edge. Arrangement and form of setal warts on head and thorax typical for genus. Spurs 2­4­4.

Male genitalia ( Fig. 3 ). Segment IX with anterior margin broadly triangular in lateral view; posterodorsally with mesal membranous lobe, which is slightly shorter in the paratype male. Preanal appendage about 1/2 length of inferior appendage, elongate, slightly wider at mid­length than at base and apex; apex truncate. Intermediate appendage composed of flat thin plates; in lateral view plates curved and arched posteroventrally, gradually tapering to rounded apex in lateral view and bearing several short stout setae along lateral margin; flattened dorsomesal plate wide basally, tapering to triangular apex, bearing 2 stout distal spines; dorsomesal plate and intermediate appendage connected by lateral sclerite, having many long stout spines along posterior margin. Inferior appendage elongate, tapering in lateral view, with basoventral projection curved mesoventrally, apex of this projection rounded; inner knob of inferior appendage straight, finger­like, with several short setae. Phallotheca rather robust, strongly curved, no spines in endotheca; phallotremal sclerite U­shaped in dorsal view.

Female and immature stages unknown.

Diagnosis. Placement of the new species among species of the genus Molanna is uncertain as it does not belong to any of the existing subgenera. The male genitalia of Molanna byssa share some similarities with M. xiaguana Malicky 1994 , whose placement in the genus is also uncertain ( Malicky 1994). Both species are similar in the shape of the preanal appendages in lateral view ( Fig. 3 A) and the inferior appendages in ventral view ( Fig. 3 C); in the possession of the dorsomesal plates of the intermediate appendages ( Fig. 3 B); and in the absence of endothecal spines ( Fig. 3 E & F). The new species differs in the forewing venation ( Fig. 2 A) and in the absence of a long row of yellow hairs through the middle of the hind wing ( Fig. 2 B). In addition, the complicated structure of the intermediate appendages armed with many stout spines distinguishes M. byssa from this and other species of the genus.

Distribution. Known only from the type locality.

Etymology. The new species is named after the Byssa River where it was collected.

Figures

FIGURE 2. Molanna byssa, new species, holotype (wing venation): A. Forewing; B. Hind wing.

FIGURE 3. Molanna byssa, new species, holotype (male genitalia): A. Lateral view; B. Dorsal view (right preanal appendage omitted); C. Ventral view; D. Caudal view; E. Phallus in lateral view; F. Phallus in dorsal view.