Caddisflies: a caddisfly
(Trichoptera: Philopotamidae:Philopotaminae) Profile prepared by Sarah Foltz Jordan and Julia Janicki, The Xerces Society for Invertebrate Conservation.
Dolophilodes columbia is a filter-feeder with the larvae occuring in running waters with moderate current. The Tucannon River, 35 miles south of Pomeroy in the Umatilla National Forest in Columbia county, Washington is the only known locality of this species and there has only been two specimens collected. Accordingly many aspects of this species is unknown, including its life history, the adult flight period, its abundance, detailed habitat information etc.. Re-evaluation of this species’ status at the known site and surrounding area is critical in identifying both its current distribution and its conservation needs.
Adult: A small, frail, moth-like insect belonging to the Philopotamidae family. In North America, adults in this family are black and up to 1 cm (0.39 in.) in length (Wiggins 2004). They are distinguished from related families by the presence of ocelli and the mesoscutum lacking setose warts (Wiggins 2004). The wing venation in this family is complete and generalized (Wiggins 2004). The species differs from the closely related and widespread D. aequalis and D. pallidipes in the elongated apical segment of the clasper, the narrowed distal portion of the basal segment of the clasper, and the small semi-circular tergum 10 from dorsal view (Denning 1989). For detailed descriptive information, Denning (1989) provides a complete description for adults, including figures.
Immature: Larvae in this family are caseless, constructing groups of silken nets shaped like fingers. The nets range in size up to 60 mm in length and 5 mm in diameter, with a small opening at the posterior end of each net to ensure flow of water through the net (Wiggins 2004). Larvae in this family range in length up to about 16 mm (0.62 in.) and are distinguished by the orange-brown head and pronotum which contrasts with the creamy white color of the rest of the body (Wiggins 2004). The membranous (as opposed to sclerotized) labrum is also diagnostic of the family (Wiggins 1996). Only the head and pronotum are sclerotized (not the meso- and metanota) and a prominent black band extends across the posterior margin of the pronotum (Wiggins 2004). The antennae, located at the anterior margin of the head capsule, are minute (Wiggins 1996, 2004). The abdomen is whitish, lacking gills and lateral fringes (Wiggins 1996). See Wiggins (1996) to distinguish the genus Dolophilodes from other genera in the family.
This species is described from a single locality in Columbia county, Washington: the Tucannon River, 35 miles south of Pomeroy in the Umatilla National Forest (Denning 1989). Abundance estimates for this species have not been done.
Forest Service/BLM Lands: This species is documented on the Umatilla National Forest in Washington.
Management: Protect all new and known sites and their associated watersheds from practices that would adversely affect any aspect of this species’ life cycle. Riparian habitat protection, including maintenance of water quality, substrate conditions, and canopy cover, would likely benefit and help maintain this species.
Research: Although several illustrations are provided in Denning (1989), a better figure of the 10th tergite and one of the aedeagus are to be desired (Wisseman 2009, pers. comm.). Wisseman (2009, pers. comm.) recommends that both the holotype (deposited in the James Entomological Collection, Washington State University, Pullman, Washington) and the paratype (deposited at California Academy of Sciences) be re-examined to see if they are indeed a unique species, or if they are in the range of variation for D. aequalis or D. pallidipes.
Denning, D.G. 1989. Eight new species of Trichoptera. Pan-Pacific Entomologist 65(2): 123-131.Wiggins, G.B. 1996. Larvae of the North American Caddisfly Genera. 2nd ed. University of Toronto Press, Toronto. 424pp.
Field, C.B., Mortsch, L.D., Brklacich, M., Forbes, D.L., Kovacs, P., Patz, J.A., Running, S.W. and M.J. Scott. 2007. Chapter 14: North America. In: Climate Change 2007: Impacts, Adaptation and Vulnerability. Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change (Parry, M.L., Canziani, O.F., Palutikof, J.P., van der Linden, P.J. and Hanson, C.E., eds.). Cambridge University Press, Cambridge, UK. Available at: www.ipcc.ch/pdf/assessment-report/ar4/wg2/ar4-wg2-chapter14.pdf.
NatureServe. 2009. “Dolophilodes columbia.” NatureServe Explorer: An online encyclopedia of life [web application]. Feb. 2009. Version 7.1. NatureServe, Arlington, Virginia. 15 Sep. 2009.
Nimmo, A.P. 2001b. Species Page – Dolophilodes pallidipes. Entomology Collection, University of Alberta. Available at: http://www.entomology.ualberta.ca/searching_species_details.php?b=caddisflies&r=312&ref=b&o=15&c=6&s=2357# (Last accessed 16 Sep 2009)
Schmid, F. 1982. Revision des trichopteres Canadiens. II. Les Glossosmatidae et Philoptamidae (Annulpalpia). Memoires de la societe entomologique du Canada. 122: 76
Wiggins, G.B. 1996. Larvae of the North American Caddisfly Genera. 2nd ed. University of Toronto Press, Toronto. 424pp.
Wiggins, G.B. 2004. Caddisflies: the underwater architects. University of Toronto Press, Toronto. 292pp
Williams D.D. and Williams N.E. 1981. Some aspects of the life history and feeding ecology of Dolophilodes distinctus (Walker) in two Ontario streams. Proceedings of the Third International Symposium on Trichoptera. Perugia (Italy), 1980. G. P. Moretti (ed.), pp. 421-429. The Hague: W. Junk.
Wisseman, R.W. 2009. Personal communication with Sarah Foltz Jordan