LIFE HISTORY AND ECOLOGY OF 
BAETISCA BAJKOV1 NEAVE, IN 
BEECH FORK OF TWELVEPOLE CREEK, 
WAYNE COUNTY, WEST VIRGINIA 
(EPHEMEROPTERA: BAETISCIDAE) 1 
By Dwight L. Chaffee 2 and Donald C. Tarter 3 
The primary objective of this study was to investigate the life 
history and ecology of the mayfly Baetisca bajkovi Neave in Beech 
Fork of Twelvepole Creek, Wayne County, West Virginia. Several 
investigators, including Traver (1931), McDunnough (1932), Berner 
(1940, 1955), Edmunds (1960), Schneider and Berner (1963), Lehm- 
kuhl (1972), Pescador and Peters (1971, 1974), Morris (1976), and 
Tarter and Kirchner (1978), have reported taxonomical and ecologi¬ 
cal information on the genus Baetisca in North America. 
Taxonomy and Distribution 
The family Baetiscidae is endemic in North America and contains 
only the genus Baetisca. The genus was established by Walsh (1862). 
Neave (1934) and Daggy (1945) described the nymph and imago, 
respectively, of B. bajkovi. The Nearctic distribution of B. bajkovi 
includes Alberta, Manitoba, and Saskatchewan in Canada (Neave, 
1934 and Lehmkuhl, 1972), and Illinois, Indiana, Minnesota (Burks! 
1953), Wisconsin (Hilsenhoff, 1970), and West Virginia in the Unit¬ 
ed States. Chaffee (1978) recorded it from 17 counties in West 
Virginia. 
The B. bajkovi nymphs were found mostly in a stream substrate 
that was predominantly small stones and sand, and with leaf litter or 
other plant material present. They were found only in the riffles, and 
were most frequently collected from water 10 to 26 cm in depth. 
'Part of a thesis submitted by the first author to the Graduate School, Marshall 
University, in partial fulfillment of the requirements for the degree of Master of 
Science, December 1978. 
2 Box 72, Spring Branch Rd., Ironton, Ohio 45638 
jDept. of Biological Sciences, Marshall Univ., Huntington, W.Va. 25701. 
* Manuscript received by the editor May 5, 1979. 
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