Keys to Orders and Families are found below and can also be found in a number of books, check Google. Keys to species are available in the references cited for the groups discussed below.
Comments on taxonomy, classification, identification, and ecology.
In the Saskatchwan River, it is my opinion that it is impossible to know the river and the ecosystem if one does not have knowledge of indiviual species, life cycles, and habitats. At the same time, species level studies are time consuming and require a high degree of skill and expertise.
The Saskatchewan River, and presumably all rivers, have habitat types such as are discussed in http://wfs.sdstate.edu/units/fishes.html for the Missouri River. To quote their fish collecting methods: *A suite of physical and hydrological measurements (e.g. velocity, depth, substrate type, bottom contour) were made at each fish collection site. In 18 segments throughout the river, fish were sampled in six macrohabitats (inside and outside bends of crossovers, main-channel crossovers, secondary channels that were either connected or unconnected to the main channel, and tributary confluences)*.
The point is that individual species are often associated with and restricted to certain microhabitats. Use of textbook random sampling methods and standard textbook sampling devices will not reveal what is in the river. This the failure of many studies that are available- poor sampling along with inadequate taxonomy.
As an example of the species situation, about 3 dozen species of Baetids are known from Saskatchewan, and nearly all are 1 cm or less in length, are all torpedo shaped with long antennae, are excellent swimmers, and are often extremely abundant and contribute to the biomass, food chain, and functioning as gatherers and scrappers of organic debris, diatoms, and organic growth in flowing water systems In government reports and studies by consultants, it is common that all Baetid types are lumped as Baetis spp. or Baetidae, but it is obvious that a great many tolerances, sensitivities, life cycles, and habitats, as well as biogeographic and evolutionary background are represented. When considering pollution or ecological function it may not be acceptable to lump all these together if a clear understanding of ecosystems is desired. While accurate and precise taxonomy require knowledge and skill, and some groups remain poorly known both biologically and taxonomically, works such as Webb (2003 ) now mean that species level work is certainly possible, and should be done when it is necessary.
Again, species level studies are time consuming and require a high degree of skill and expertise. While numerous studies have been done on prairie flowing waters, accurate and dependable taxonomy is a cause for caution, and many studies focus not on the species, but rather the genus or even family level. Here I do not attempt to review all current literature but rather to point out taxonomic studies have been completed for the prairies: Trichoptera, (Smith 1975, 1984); Plecoptera ( Dosdall 1976, Dosdall and Lehmkuhl 1979); Ephemeroptera ( Lehmkuhl 1970, 1976, 1979, 1980,Webb 2002); Hemiptera (Brooks and Kelton 1967); Culicidae (Rempel 1950, 1953); Simuliidae (Fredeen 1981); Chironomidae ( Mason 1978, 1983); and Dytisciae (Larson 1975). The reader who requires additional detail can refer to these references for species level keys, descriptions, and biological and distributional information, but see the Mayflies, Ephemeroptera link above. Other links to Stoneflies, etc will follow soon..
Diversity, Orders, Families, Species
More than 500 species of aquatic and semiaquatic insects inhabit the flowing waters of the prairies including Saskatchewan. Most are in the Orders and Families Ephemeroptera , Plecoptera, Trichoptera, and Chironimidae, but Simuliidae, Hemiptera, Coleoptera, Megaloptera, Lepidoptera and others are also present.
Excellent and extensive information on general biology and taxonomic keys at the higher levels (Order, Family, Genus) can be found for all groups in Merritt and Cummins, and Berg (2008), and also useful are, for example, Clifford (1991) (available on line), Edmunds, Jensen, and Berner (1976), Lehmkuhl (1979), Wiggins ( 1996), plus many others.
The keys and photos below cover the Order and Family for all of North America, not just Saskatchewan. The material below was published in 1975, but there have been relatively few changes at the Family and Order level since then.
Combine the links below with the Guide above for identifying Ephemeroptera, Plecoptera, and Trichoptera and the other Orders and Families of Aquatic Insects in North America. Again, both pdf and power point versions are given.
Species: discussion, especially pertaining to Saskatchewan The diversity of aquatic insects in prairie flowing waters is very high as a result postglacial recruitment of species from as far away as the Colorado River System and Eurasia, plus the nature of waterways such as the Saskatchewan River, which is ecologically a large stream with clear cool water, a variety of rubble, gravel, sand, fallen branch and log habitats, along with submerged vegetation and roots. This is in contrast to the muddy waters and mucky substrates found in many prairie rivers such as the Missouri to the south. Probably over 1000 aquatic and semiaquatic species inhabit prairie habitats, and at least half this number are found in streams and rivers, where they contribute to nutrient cycles and energy flow. Aquatic insects often represent a large biomass with great biodiversity in pristine prairie rivers, but dams, sewage, and agricultural runoff and other pollution have destroyed suitable habitat and favourable environmental conditions in large areas, thus eliminating natural biodiversity in large portions of prairie flowing waters. Fortunately, some areas show minimal damage and appear to be in a near original state in terms of biological communities and water quality. On the other hand, laws (See Boyd) protecting flowing waters as well as other aspects of the environment are judged my many to be weak, and large areas of flowing waters have not been studied in detail to gain an understanding of ecological functions or biodiversity, especially the changes in function and biodiversity from midstream regions back to the sources in the mountains in the west, and downstream changes into the deltas and lakes to the east.