Biological Diversity of Minnesota Caddisflies
Insecta, Trichoptera
ZooKeys No. 189
By David C. Houghton
August 2012
Pensoft
ISBN: 9789546426345
389 pages, Illustrated
$195.00 Paper original
This work contains illustrations, statewide abundances, distributions, adult flight periodicities, and habitat affinities for all of the 277 known Minnesota caddisfly species. These species are based on examination of >300,000 specimens from 2,166 collections of 937 Minnesota aquatic habitats from 1890 to 2007. Four species: Lepidostoma griseum (Lepidostomatidae), Psilotreta indecisa (Odontoceridae), and Phryganea sayi and Ptilostomis angustipennis (Phryganeidae) are added to the known fauna. An additional 31 dubious species records are removed for various reasons. Biological diversity was highest in the Lake Superior and Northern regions of the state, intermediate in the Southeastern, and lowest in the Northwestern and Southern. Many species, especially within the long-lived shredder families Limnephilidae and Phryganeidae, have decreased in distribution and abundance during the past 75 years, particularly those once common within the Northwestern and Southern regions. Many species now appear regionally extirpated, and a few have disappeared from the entire state. This loss of species in the Northwestern and Southern regions, and probably elsewhere, is almost certainly related to the conversion of many habitats to large-scale agriculture during the mid-20th century. With aseline data now in place, any future changes to the Minnesota caddisfly fauna can be evaluated with much greater confidence and precision.