Paracapnia
Hanson, 1946
small winter stoneflies
Paracapnia is a of in the , to North America. The genus contains at least five described , including the snowfly (Paracapnia angulata) and the northeastern snowfly (Paracapnia opis). Members of this genus are notable for their of acidic stream conditions, with some species increasing in abundance in waters affected by acid precipitation.
Identification
Paracapnia are distinguished from other by their small size and winter-emergent . Specific species-level identification requires examination of and patterns. Paracapnia opis (northeastern snowfly) was previously described as Paracapnia curvata, now synonymized.
Habitat
Headwater streams, particularly in mountainous regions. Paracapnia angulata occurs in Appalachian streams with pH ranging from 4.5 to 7.5, demonstrating of acidic conditions.
Distribution
to North America. Records include: Russian Far East, Arkansas, California, Connecticut, Colorado, and West Virginia.
Seasonality
Winter-emergent , typical of ().
Ecological Role
of Paracapnia angulata can be substantial in acidic streams, reaching 106.2 mg·m⁻²·yr⁻¹ in streams with pH 4.26. The contributes to stream as both and processor of matter.
Human Relevance
Used as bioindicators of stream health and acidification impacts. Paracapnia angulata serves as a model organism for studying effects of acid precipitation on aquatic .
Similar Taxa
- Other Capniidae generaParacapnia is distinguished by specific genitalic structures and geographic distribution; other overlap in size and seasonal activity but differ in morphological details.
More Details
Acid tolerance
Paracapnia angulata increases in abundance in acidic streams affected by acid precipitation, with highest recorded in streams with pH 4.26. This contrasts with many other aquatic that decline under acidified conditions.
Taxonomic note
Paracapnia curvata (Hanson, 1946) is now synonymized with Paracapnia opis (Newman, 1839).