410 



NEW GENUS AND SPECIES OF MAY-FLY FROM TASMANIA, 



Family SIPHLURIDAE. 

 Genus T A s m a n o p ii l e b i a, n.g. (Plate xxxiv., and Tt'xl-tigs. 1, 2.) 



Insects Iiaving an expanse of about one inch, the hindwing about half as 

 long and two-thirds as wide as the fore. Venation closely resembling that of 

 Onisciguster. Forelegs in male about three-fourths the leng-th of forewing, those 

 of female much shorter. Tarsus of hindleg longer than tibia. Tai'sal claws 

 dissimilar, one blunt and one sharply hooked. Abdomen narrowly cylindrical, 

 without lateral dilatations on any of the segments, t'erci present, longer than 

 abdomen, but the appendix dorsalis completely absent in both sexes. 



Genotype, Tasmanophlehia lacustris, n. sp. 



This genus is very close to the New Zealand genus Oniseiya-'<ter, from which 

 it is to be distinguislied by its much smaller size, its narrow cylindrical abdomen 

 ^athout any lateral dilatations, the complete absence of the appendix dorsalis 

 in b(jth sexes, and also by the habit of the larva dwelling in the still water of 

 lakes. The larvae of all the other Siphlurid<ie known in New Zealand and 

 Australia dwell in the fast running water of mountain streams. 



Tasmanophlebia lacustris, n. sp. (Plate xxxiv., and Text-figs. 1, 2.) 



6, Imago: Total length, 14; forewing, 12; hindwing, 5.7; expanse of 

 wings, 26 mm. 



Text-fig. 1. Tasvtaiwp/i/ebia lanislris, n.g. et sp., genitalia of male imago. 



a, lateral view of end of abdomen, showing base of cercus (c), left clasper (cl), aifl 



penis (p). Right clasper omitted. 9, lit, the last two segments of tlie abdomen. 



(x 40). /), Ventral view of distal portion of penis, (x 40). 



Head and thorax rich dark brown. Forelegs mm. long, dark brown; 

 middle- and hivdlegs medium brown. 



Ahdom-en dark shining brown, the segments separated very distinctly by 



