97 



Doy: Ephemeroptera 



Fig. 3:22. Ephemerella nymphs, a, doddsi, in dorsal view with ventral view of abdomen showing 

 suction disc; b, ilavilinea, fore leg; c, co/orodensi's, fore leg; d, glacialis carsona, head and 

 thorax; e, proserpina (a,e, Needham, Traver, and Hsu, 1935; b,c, Walley, 1937; d, Day, 1952). 



Nymphs 



Teeth or spines present on the anterior margin of the 



fore femur 2 



No teeth or spines on the anterior margin of fore femur; 



large occipital tubercles present 4 



Occipital tubercles absent; a complete adhesive disc 

 on venter of abdomen (fig. 3:22a); widespread, montane 



doddsi Needham 1927 



Occipital tubercles present 3 



"Thumb" at distal end of fore tibia long and sharp 

 (fig. 3:22c); abdominal spines moderate; widespread, 



montane coloradensis Dodds 1923 



"Thumb" at distal end of fore tibia short and blunt 



Cfie. 3:226); abdominal spines very short; widespread 



flavilinea McDunnough 1926 



I 4. Dorsal abdominal spines forming a rather regular series; 

 submedian tubercles of prothorax 3 on each side, the 

 anterior high and blunt, the posterior pair small; moder- 

 ate, well-defined tubercles arise from submedian ridges 

 of the mesonotum; dorsal spines very prominent on 

 segments 2-9, those on 8 and 9 about 40 per cent longer 

 and heavier than those of segments 4-7 (fig. 3:22d); 

 east slope Sierra Nevada . . . .glacialis carsona Day 1952 



— Dorsal abdominal spines on tergites 8 and 9 very much 

 enlarged, being from 2 to 4 times as large as preceding 



pairs 5 



5. Submedian spines of pronotum heavy and blunt, 3 on 

 each side, with the anterior spine much larger and 

 higher than the posterior pair (fig. 3:22e); widespread, 

 montane proserpina Traver 1934 



E. yosemite Traver 1934, reported from California, is here 

 regarded as a synonym of E. proserpina Traver 1934 



— Submedian spines of pronotum rather slender, sharp 

 pointed, 2 on each side; anterior spine sometimes 

 higher than posterior spine; widespread, montane .... 

 spinifera Needham 1927 



Genus Ephemerella Walsh: Needhami Group 



Key to the California Species 



Adults 



1. Wing 10-11 mm. in length; fore leg yellow; venation 



red-brown; tails purple-brown (fig. 3:23a) 



euterpe Traver 1934 



— Wing 8 mm. in length; fore leg brown; venation dark 



purplish brown; tails dark brown (fig. 3:236) 



maculata Traver 1934 



Nymphs 



1. Legs banded; venter of abdomen marked with reddish 

 lateral triangles; length 10-11 mm.; tails dark brown 



(central California coastal) euterpe Traver 1934 



- — Legs not banded; ventral markings consist of dark 

 bands on the anterior margins and lateral extensions of 

 these; length 8-9 mm.; tails yellowish (coastal and 

 San Gabriel Mts.) maculata Traver 1934 



basis of description given, E. sierra Mayo 1952 cannot be 

 On the separated from the type specimens of E. spinifera. 



