Fend, S. V., and J. L. Carter. “Rhynchelmis Subgenus Sutroa Eisen New Rank, With Two New Species from Western North America (Annelida, Clitellata, Lumbriculidae)”. Zootaxa, vol. 3760, no. 2, Jan. 2014, pp. 180–210, doi:10.11646/zootaxa.3760.2.3.