Trichoptera: Limnephilidae of Gunnison County, ColoradoGrammotaulius lorettaeDenning 1941Updated 24 Feb 2026
TSN 116314  Grammotaulis case, part of the head and a few legs are barely peeking out of the left side. DescriptionLarval cases are often the biggest structures pulled out of a pond in the upper East River Valley or in the ponds near Irwin Lake in the late spring or early summer. They are always found with Carex aquatilius or Carex rostrata, or another large grass they can use to build their 10cm long cases. They have a tan or golden head with brown spots. The earliest instars are easily confused in the pond with Limnephilus picturatus. However, L. picturatus has a darker head and is a small to average sized caddis in our valley in its final instars, while Grammotaulis larvae are big and their cases are uniquely gigantic in their last few instars. Also L. picturatus is found at higher elevations, while Grammotaulius are present at or below 3000 meters.Good LinksOn this website:Limnephilidae Introduction Other Websites: Photos, Map, Taxon Identifier Numbers - from the Global Biodiversity Information Facility Grammotaulius lorettae at GBIF Photos, Map, Museum specimens, DNA - Barcodinglife.org ReferencesAl Mousa,MDA; Nachappa,P; Ruiter,DE; Givens,DR and Fairchild,MP 2022 Caddisflies (Insecta: Trichoptera) of montane and alpine lakes of northern Colorado (USA). Western North American Naturalist, 82(3), pp.563-576. PDFQuote from page 571: "Limnephilus castor Ross and Merkley, 1952, was less common but found as recently as 2020, whereas the remaining endemic species were less common, patchily distributed, and not recently encountered. ---snip--- Grammotaulius lorettae Denning, 1941, was encountered only once from a lake in Larimer County in 1995 (Table 2, Supplementary Material 1)." Balik,JA; Leitz,C; Washko,SE; Cleveland,B; Krejsa,DM; Perchik,ME; Stogsdill,A; Vlah,M; Demi,LM; Greig,HS and Shepard,ID 2022 Species-specific traits predict whole-assemblage detritus processing by pond invertebrates. Oecologia, 199(4), pp.951-963. PDF Balik,JA; Taylor,BW; Washko,SE and Wissinger,SA 2018 High interspecific variation in nutrient excretion within a guild of closely related caddisfly species. Ecosphere, 9(5) p.e02205. PDF Denning, DG 1941 The genus Grammotaulius in North America, with the description of a new species (Trichoptera, Limnephilidae). The Canadian Entomologist 73:232-235. Abstract: "Four species of the genus Grammotaulius, one of which is now considered a synonym, have been recognized in North America. These have been recorded only from Greenland, Canada, and northwestern United States. In August, 1940, Dr. C. E. Mickel and Mr. H. E. Milliron collected a series including both sexes of a new species in Colorado." Flint,OS, Jr. 1960 Taxonomy and biology of Nearctic limnephilid larvae (Trichoptera), with special reference to species in eastern United States. Entomologica Americana 40:1-120. Describes the larvae of this species from a pond near Irwin. 
Herrmann,SJ; Ruiter,DE and Unzicker,JD 1986: Distribution and records of Colorado Trichoptera. Southwestern Naturalist 31(4), 421-457. Notes this species is found in Gunnison County. McCullagh,BS; Wissinger,SA and Marcus,JM 2015 Identifying PCR primers to facilitate molecular phylogenetics in Caddisflies (Trichoptera). Zoological Systematics, 40(4) 459 PDF Schmid,F 1950 Monographie du genre Grammotaulis Kolenati (Trichoptera, Limnophilidae). Revue Suisse de Zoologie 57(7):317-52. The author studied adults of Grammotaulius. Schmid,F 1964 Some nearctic species of Grammotaulius Kol (Trichoptera, Limnophilidae). Canadian Entomologist 96(6):914-917. More studies of Grammotaulius adults. Wissinger,SA; Brown,WS and Jannot,JE 2003 Caddisfly life histories along permanence gradients in high altitude wetlands in Colorado (U.S.A.). Freshwater Biology 48(2). Abstract PDF Zuellig,RE; Heinold,BD; Kondratieff,BC and Ruiter,DE 2012 Diversity and Distribution of Mayflies (Ephemeroptera), Stoneflies (Plecoptera), and Caddisflies (Trichoptera) of the South Platte River Basin, Colorado, Nebraska, and Wyoming, 1873-2010. U.S. Geological Survey Data Series 606, 257 p. PDF - caution 46MB Quote from page 85: "The type series of the species was collected from Cameron Pass, Colorado at approximately 10,250 ft elevation (Denning, 1941). Roger Blahnik at the University of Minnesota, kindly examined the type collection labels, and there was no additional information to determine whether it was collected from the South Platte or North Platte River Basins. The only confirmed record available for the SPRB, listed above, was collected about 6 mi northeast of Cameron Pass. This species typically occurs in heavily vegetated wetlands and autumnal lakes (Wissinger and others, 2003)." The elevation is 9,300 feet and the adults were found in July. |