Nymphs of three species of Baetisca (Ephemeroptera: Baetiscidae) have been collected in Wisconsin. Baetisca laurentina was most abundant. occurring in a wide variety of streams and occasionally in impoundments. Baetisca obesa was uncommon and occured only in two large rivers, while B. lacustris was somewhat more common and inhabited medium to streams. Except for a few nymphs of B. lacustris that were collected from Green Bay on Lake Michigan, no Baetisca nymphs were found within 100 km of Lake Michigan.
Hilsenhoff, William L.
"Identification and Distribution of Baetisca Nymphs (Ephemeroptera: Baetiscidae) in Wisconsin,"
The Great Lakes Entomologist: Vol. 17
, Article 1.
Available at: http://scholar.valpo.edu/tgle/vol17/iss2/1