The highly developed anterior process of the mesothorax, is described as a useful field character for identifying adults of Acentrella and Heterocloeon in the Nearctic. This presumed adult synapomorphy suggests a sister relation- ship of the two genera.
Waltz, R. D.
"Field Recognition of Adult Acentrella and Heterocloeon (Ephemeroptera: Baetidae),"
The Great Lakes Entomologist: Vol. 26
, Article 7.
Available at: https://scholar.valpo.edu/tgle/vol26/iss4/7