Updated 25 July 2017
DescriptionLarvae have an apical-lateral spine or spur on their anal proleg. They also have little stubby gills on their abdominal segments.
Locations CollectedAllan (1975) reports this species from Cement Creek. Vance and Peckarsky (1997) report R. hyalinata from the East River and Copper Creek.
NotesR. hyalinata is similar to Rhyacophila vocala. R. vocala has been reported from 9400 feet in neighboring Pitkin county, so is likely to be present in Gunnison County. Be careful with identifications! Adults may be neccessary to confirm the species.
Good LinksOn this website:
Introduction to Rhyacophila
Photos, Map, Museum specimens, DNA - Barcodinglife.org
ReferencesAllan,JD 1975. The distributional ecology and diversity of benthic insects in Cement Creek, Colorado. Ecology 56:1040-1053. PDF
Banks,N 1905 Descriptions of new neuropteroid insects. Transactions of American Entomological Society 32, 1-20.
Dodds,GS and Hisaw,FL 1925 Ecological studies on aquatic insects. IV. Altitudinal range and zonation of mayflies, stoneflies and caddisflies in the Colorado Rockies. Ecology 6(4)380-390. Abstract PDF
Herrmann,SJ; Ruiter,DE and Unzicker,JD 1986 Distribution and records of Colorado Trichoptera. Southwestern Naturalist 31 4, 421-457.
They note the habitat for this species is streams and rivers, the altitudinal range is 2804 to 3542m and adult collection dates are 20 July to 8 September. They list this species as present in Gunnison county.
Short,RA and Ward,JV 1980 Macroinvertebrates of a Colorado high mountain stream. The Southwestern Naturalist, 23-32. PDF
Smith,SD 1968 The Rhyacophila of the Salmon river drainage of Idaho with special reference to larvae. Annals of the Entomological Society of America 61 3, 655-674.
Has a key to larvae that includes R. hyalinata. Does not separate R. hyalinata from R. vocala. R. vocala is present in the Colorado River Drainage of Pitkin County at 2853 meters elevation.
Larvae description quoted: " Head dark brown, paler anteriorly, and with darkened muscle scars posteriorly, ventral surface usually light brown with a few pale muscle scars (like Figure 20); maxillary palpus with second segment equal in length to first; left mandible long and slender, with apical tooth long, subapical tooth small, mesal area with a very small tooth that appears to be no more than an emargination of the mesal margin in most individuals, right mandible long and slender, with an apical tooth, 1 small subapical tooth ventrally, 1 subapical tooth dorsally, and 1 mesal tooth, mesal margin between mesal tooth and subapical dorsal tooth minutely serrate (like Figure 22). Pronotum brown, paler anteriorly. Abdomen with lateral, single, fleshy protuberances on segments Il-Vill (like Figures 23, 24); anal proleg with a small baso-ventral hook, apico-lateral spur elongate and stout, projecting away from the body, and anal claw with distal tooth furcate, 2- to 4-branched, basal tooth when present small, not furcate (Figure 25). Length of mature larvae 20-25 mm."
Vance,SA; Peckarsky,BL 1997 The effect of mermithid parasitism on predation of nymphal Baetis bicaudatus (Ephemeroptera) by invertebrates. Oecologia 110, 147-152.
They found that Kogotus modestus ate significantly more parasitized than unparasitized B. bicaudatus. However, Rhyacophila hyalinata caught and ate equal numbers of parasitized and unparasitized nymphs. They attribute this to the behavior of parasitized nymphs and different hunting behaviors of the predators. Parasitized nymphs drifted less, which increased encounter rates with Kogotus nymphs. However R. hyalinata larvae are ambush predators and catch parasitized and unparasitized nymphs equally. They hypothesize that avoiding fish predation by drifting less is a greater advantage to the parasite than the losses suffered by increased stonefly predation.
Wold,JL 1973 Systematics of the genus Rhyacophila (Trichoptera: Rhyacophilidae) in western North America with special reference to the immature stages (Doctoral dissertation). PDF
Quote from page 57: Biology (Hyalinata Group): Head capsule measurements were variable, but apparently are (in mm, ):
II, .54 to .66. (6 larvae);
III, .84 to 1.10 (54 larvae);
IV, 1.18 to 1.80 (177 larvae);
V, 1.90 to 2.48 (104 larvae),
A distinct seasonal succession of life stages was not apparent.
Brown,WS 2004 Trichoptera of Gunnison County, Colorado, USA