|Adult Pteronarcys californica|
P. californica nymphs, or larvae, can grow to lengths in excess of 5 centimetres (2 in). The nymphs' dorsal side (back) is dark in colour, although their ventral side (belly) is lighter. The colouring can vary, and subtle patterns are occasionally found on the abdomen. They are detritivores, eating stream debris partially broken down by other organisms. They are "shredders" as a functional feeding group, breaking down large bits of detritus into smaller while feeding. The adults are also large, and the abdomen, leg joints, and several thorax joints are a bright orange colour. Two pairs of large wings, kept flat against the body when at rest, are longer than the body. The adult carries its eggs at the end of the abdomen and look like a cluster of orange salmon eggs.
Range and habitat
The nymphs live three to four years in the water before emergence. Immediately prior to emerging, the nymphs congregate near the shoreline in shallow water on partially exposed rocks. To emerge, the nymphs crawl from the water to rocks or the shore, and split the nymphal exoskeleton. The adults emerge from the exuviae ready to mate.
The emergence is also followed closely by fly-fishermen, and is one of the highlights of the spring fishing season.
- Pteronarcys californica. NatureServe Explorer. Version 7.1. Accessed 16 January 2016.
- Giant Salmonfly - Pteronarcys californica. Montana Field Guide. Montana Natural Heritage Program. Retrieved 16 January 2016.
- Jewett, S. G., Jr. "Plecoptera." In: Aquatic Insects of California, Usinger, R. L. (Ed.) 155-181, Berkeley, University of Nebraska Press.
- Elder, J. A. and Gaufin, A. R. 1973. Notes on the occurrence and distribution of Pteronarcys californica Newport (Plecoptera) within streams. Great Basin Naturalist 33:218-220.
- Rockwell, I. P. & Newell, R. L. (2008). Note on mortality of the emerging stonefly Pteronarcys californica on the Jocko River, Montana, USA. Western North American Naturalist 69(2): 264-266.