Montana Ephemeroptera List Summary

Within the mayflies our mountain species are now pretty well known, but our prairie species remain very poorly known.

Recent Discoveries

In 1995 I finally verified the most unusual Macdunnoa nipawinia in Montana based on a specimen for the lower Yellowstone River. I have a great many mayfly collections that have not been seriously examined yet.

Research Needs

It is clear that we have many of the big-river species still present in Montana and these deserve quick and special attention. Our prairie baetids, tricorythids, and caenids are very poorly known yet. Some of our mountain groups such as the Ephemerellidae are so well known that field recognition is now possible. This should allow the development of some solid rapid bioassesment techniques.

Some changes for the Montana area fauna since 1976

  • Acanthomola pubescens Whiting & Lehmkuhl is a new genus and new species of 2-tailed heptageniid from the Saskatchewan River drainage
  • Analetris was moved from the Siphlonuridae to the Analetridae
  • Baetis parvus Dodds is the same as Diphetor hageni (Eaton)
  • Baetis hageni Eaton is now Diphetor hageni (Eaton)
  • Baetis insignificans McDunnough is now Acentrella insignificans (McDunnough)
  • Baetis intermedius Dodds is the same as B. tricaudatus Dodds
  • Baetis quilleri Dodds is now Fallceon quilleri (Dodds)
  • Callibaetis coloradensis Banks is the same as C. americanus Banks
  • Callibaetis nigritus Banks is the same as C. americanus Banks
  • Caurinella idahoenis Allen is a new genus, new species of Ephemerellidae from Idaho and Montana
  • Centroptilum in our area are now Procloeon
  • Cercobrachys is a new caenid genus for several, mostly new species
  • Dactylobaetis is now Camelobaetidius
  • Ephemerella subgenera now recognized as genera
  • Heptagenia divided into several genera based on new nymph/adult associations
  • Isonychia was moved from Siphlonuridae to the Oligoneuriidae and now to the Isonychiidae
  • Leucroduta is a new genus for some Heptagenia species
  • Macdunnoa nipawinia Lehmkuhl is a new genus and new species of heptageniid with reduced gills from the Saskatchewan River
  • Nixe is a new genus for some Heptagenia species
  • Pseudiron removed from the Heptageniidae to its own family
  • Pseudocloeon edmundsi Jensen is the same as Baetis punctiventris (McDunnough)
  • Pseudocloeon turbidum McDunnough is now Acentrella turbida (McDunnough)
  • Raptoheptagenia is a new genus for Heptagenia cruentata Walsh and its nymph, which was previously thought to be Anepeorus

Acknowledgments

  • W.P. McCafferty identified some difficult Montana baetid specimens.
  • R. Wills Flowers verified some Montana heptagenids.
  • Jack Aloty identified many Montana Ameletus specimens.
  • A. V. Provonsha identified many Montana caenid specimens.

13 APR 1996 D.L. Gustafson
AIM home page
dlg@rivers.oscs.montana.edu