The nymph of Centroptilum walshi McDunnough is described. C. walshi appears to be bivoltine in Wisconsin, with emergences throughout June into early July and from late August to early November. Mature nymphs were smallest when stream temperatures were the warmest. The nymphs were closely associated with Ranunculus sp., and numbers increased when the Ranunculus beds became more dense.
Bergman, Edward A. and Hilsenhoff, William L.
"Description of the Nymph of Centroptilum Walshi (Ephemeroptera: Baetidae), with Biological Notes,"
The Great Lakes Entomologist: Vol. 11
, Article 1.
Available at: http://scholar.valpo.edu/tgle/vol11/iss2/1