Statement of Need and Reasonableness: August 10, 2012
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CADDISFLIES ONLY Notations Used E Endangered T Threatened SC Special Concern N None (location records maintained by DNR, in most cases) N (X) None, and probably extirpated from Minnesota (location records maintained by DNR, in most cases) -- None (location records not yet maintained by DNR) * Change in scientific name accompanies change in status CHANGE IN STATUS; STATUS SHEET PROVIDED Common Name Scientific Name Current Proposed Status Status A Species of Northern Caddisfly Anabolia ozburni -- SC * A Species of Northern Caddisfly Asynarchus rossi SC T A Species of Long Horned Caddisfly Ceraclea brevis SC N Vertrees's Ceraclean Caddisfly Ceraclea vertreesi SC N Headwaters Chilostigman Caddisfly Chilostigma itascae E T A Species of Caddisfly Goera stylata -- T A Species of Purse Casemaker Caddisfly Hydroptila novicola SC N A Species of Purse Casemaker Caddisfly Hydroptila quinola -- SC A Species of Purse Casemaker Caddisfly Hydroptila rono -- T A Species of Purse Casemaker Caddisfly Hydroptila waskesia -- E A Species of Northern Caddisfly Ironoquia punctatissima -- T A Species of Caddisfly Lepidostoma libum -- T A Species of Northern Caddisfly Limnephilus janus -- E A Species of Northern Caddisfly Limnephilus secludens -- E A Species of Purse Casemaker Caddisfly Ochrotrichia spinosa -- E A Species of Long Horned Caddisfly Oecetis ditissa -- T A Species of Purse Casemaker Caddisfly Oxyethira ecornuta SC T A Species of Netspinning Caddisfly Parapsyche apicalis -- T A Species of Tube Casemaker Caddisfly Polycentropus glacialis -- T A Species of Tube Casemaker Caddisfly Polycentropus milaca SC E A Species of Saddle Casemaker Caddisfly Protoptila erotica -- SC A Species of Saddle Casemaker Caddisfly Protoptila talola SC N A Species of Caddisfly Setodes guttatus SC N A Species of Long Horned Caddisfly Triaenodes flavescens -- SC A Species of Long Horned Caddisfly Ylodes frontalis -- T EXTRACTED FROM Proposed Amendment of Minnesota Rules, Chapter 6134: Endangered and Threatened Species Statement of Need and Reasonableness: August 10, 2012 SPECIES STATUS SHEET SCIENTIFIC NAME: Anabolia ozburni COMMON NAME: A Species of Northern Caddisfly CURRENT MINNESOTA STATUS: None PROPOSED MINNESOTA STATUS: Special Concern BASIS FOR PROPOSED MINNESOTA STATUS: Larvae of the genus Anabolia typically inhabit lakes, marshes, and low gradient rivers. Cases are composed of organic material, including leaves, twigs, and pieces of bark, usually arranged lengthwise. Mature larvae range 20–30 mm in length depending on the species, with cases up to 50 mm. Larvae consume decaying plant tissue and are important processors of allochthonous debris. Adult males are about 15 mm in length, with mottled wings. In Minnesota, Anabolia ozburni is known prior to 1950 from the northwestern third of the state. Extensive recent surveys, however, have located it from only single sites in Hubbard and Douglas County, and a series of three adjacent sites in Becker and Mahnomen Countries. All collections were of adults in June and July 2000. All recent populations have been found in low gradient streams, often right at their lentic headwaters. Specimens of this genus tend to be conspicuous and easy to collect, so it is unlikely that many additional populations have been missed by recent collecting. Little is known about the specific habitat requirements of A. ozburni. Anabolia species tend to be intolerant of habitat disturbance, especially that of the riparian zone since they depend on terrestrial input for their food source. The apparent decrease in distribution of A. ozburni—especially in the northwestern portion of its Minnesota range—is alarming and likely due to habitat loss in these areas. Until more is known about the specific habitat needs and population status of this species, Special Concern status is reasonable and needed. SELECTED REFERENCES: Houghton, D.C. 2007. The effects of landscape-level disturbance on the composition of caddisfly (Insecta: Trichoptera) trophic functional groups: evidence for ecosystem homogenization. Environmental Monitoring and Assessment 135: 253–264. University of Minnesota Insect Collection. 2009. UMSP Trichoptera Biota database. University of Minnesota, St. Paul, Minnesota. <http://www.entomology.umn.edu/museum/databases/>. Accessed 05 August 2009. Wiggins, G.B. 1996. Larvae of the North American caddisfly genera (Trichoptera). Second edition. University of Toronto Press, Ontario. 457 pp. EXTRACTED FROM Proposed Amendment of Minnesota Rules, Chapter 6134: Endangered and Threatened Species Statement of Need and Reasonableness: August 10, 2012 SPECIES STATUS SHEET OLD SCIENTIFIC NAME: Asynarchus rossi NEW SCIENTIFIC NAME: Limnephilus rossi COMMON NAME: A Species of Northern Caddisfly CURRENT MINNESOTA STATUS: Special Concern PROPOSED MINNESOTA STATUS: Threatened BASIS FOR PROPOSED MINNESOTA STATUS: Larvae of the genus Limnephilus feed primarily on coarse detritus, and are commonly found in lentic habitats including ponds, lake margins, and marshes; some have been reported from streams and cold springs. Mature Limnephilus larvae are up to 29 mm in length; cases may be constructed from sand, pebbles, bark, wood, and leaves in various arrangements. Adult males are about 15 mm in length, wings irrorate, dark brown and pale yellow. When assigned Special Concern status in 1996, Limnephilus rossi had only been documented in Minnesota by the collection of a single male specimen from Valley Creek in Washington County in 1965. After extensive recent sampling throughout the state, this species has now been relocated in Valley Creek and has also been discovered in Grand Portage Creek in Cook County. This caddisfly appears to be fairly abundant at the former locality; many adults have been collected there in October of 1996 and September of 1997. The latter locality has yielded only a single adult specimen, in late August 2000. Species of Limnephilus are usually very conspicuous and easy to collect, so it is unlikely that many additional populations have been missed by recent survey efforts. Limnephilus species tend to be intolerant of habitat disturbance, especially modification of the riparian corridor since they depend on terrestrial input for their food source. The two collecting sites are separated by nearly 500 km, but are both high gradient, rocky, second order streams. Grand Portage Creek has good riparian protection from the national monument and tribal lands that surround it. Valley Creek, however, is in an area of intense urban development. The observed disjunct distribution pattern has been noted previously in Michigan, Wisconsin, and Quebec where L. rossi is also rare and highly localized. Little is known about the specific habitat needs of this species and why it exhibits this distribution pattern. Due to the rarity of L. rossi in Minnesota, the high rate of urban development around Valley Creek, and the low abundance of this species in Grand Portage Creek, reclassification from Special Concern to Threatened status is reasonable and needed. SELECTED REFERENCES: Houghton, D.C. and R.W. Holzenthal. 2003. Updated conservation status of protected Minnesota caddisflies. The Great Lakes Entomologist 36: 35–40. Leonard, J.W. and F.A. Leonard. 1949. Noteworthy records of caddis flies from Michigan, with descriptions of new species. Occasional Papers of the Museum of Zoology 520:1-35. Ruiter, D.E. 1995. The genus Limnephilus Leach (Trichoptera: Limnephilidae) of the New World. Ohio Biological Survey Bulletin, New Series Volume 11. 200 pp. University of Minnesota Insect Collection. 2009. UMSP Trichoptera Biota database. University of Minnesota, St. Paul, Minnesota. <http://www.entomology.umn.edu/museum/databases/>. Accessed 05 August 2009. Wiggins, G.B. 1996. Larvae of the North American caddisfly genera (Trichoptera). Second edition. University of Toronto Press, Ontario. 457 pp. EXTRACTED FROM Proposed Amendment of Minnesota Rules, Chapter 6134: Endangered and Threatened Species Statement of Need and Reasonableness: August 10, 2012 SPECIES STATUS SHEET SCIENTIFIC NAME: Ceraclea brevis COMMON NAME: A Species of Long Horned Caddisfly CURRENT MINNESOTA STATUS: Special Concern PROPOSED MINNESOTA STATUS: None BASIS FOR PROPOSED MINNESOTA STATUS: Larvae of the genus Ceraclea are found in lentic and lotic waters, usually on bottom substrates. Many species feed on detritus; some are specialized for feeding on freshwater sponges and are found burrowing within these colonies. Mature Ceraclea larvae are about 12 mm in length, stout bodied, with abdominal gills arranged in clusters. Cases are usually constructed of sand with a flanged dorsal lip and are wide anteriorly, tapered, and curved distally; species associated with sponges are usually made entirely of silk and may incorporate pieces of sponge. Adult males are between 11-16 mm. in length, brownish in color, with irregular scattering of hyaline spots. Ceraclea brevis is known worldwide from a single adult specimen, which was collected in August 1965 at the Garrison Ranger Station in Crow Wing County, Minnesota. Despite extensive recent collecting in that area and elsewhere, the species has yet to be rediscovered. Moreover, C. brevis is very similar in appearance to C. tarsipunctata, a very common species in Minnesota. Thorough recent examination of the only known C. brevis specimen suggests that it may, in fact, be an aberrant specimen of C. tarsipunctata. Thus, Special Concern status of C. brevis should be withdrawn until both its legitimacy as a distinct species and its continued presence in