Capniidae Banks, 1900

Myers, Luke William, Kondratieff, Boris C, Grubbs, Scott A, Pett, Lindsey A, DeWalt, R. Edward, Mihuc, Timothy B & Hart, Lily Veronica, 2025, Distributional and species richness patterns of the stoneflies (Insecta, Plecoptera) in New York State, Biodiversity Data Journal 13, pp. e 158952-e 158952 : e158952-

Capniidae Banks, 1900

Notes

Capniidae are commonly referred to as Snowflies ( Stark et al. 1998, Stark et al. 2012). They are amongst the first to emerge as adults during the late autumn and winter, and together with Taeniopterygidae are referred to historically as " winter stoneflies ". Eighteen species and three genera of Capniidae are known from New York, some of which have been infrequently reported. A recent (since 2000) taxonomic treatment of the eastern North American species of Capniidae does not yet exist. Instead, we have to rely on a combination of recent and older literature. For example, Ross and Ricker (1971) provided the most recent taxonomic review of the common winter stonefly genus, Allocapnia Claassen, 1928 , including evolutionary and post-Pleistocene dispersal hypotheses, but several species have been described during the intervening 50 + years. Additional important taxonomic references to identify New York taxa include Hitchcock (1974), Nelson and Baumann (1987), Stark and Baumann (2004), Stark and Kondratieff (2012), and Burton (2019). It is likely that all Allocapnia larvae undergo a diapause deep in the sediments of streams, a condition that breaks in autumn allowing growth to continue through the winter ( Pugsley and Hynes 1985).

Adult collection dates for this family range from mid-November through early June (Fig. 7 ). Capniidae in New York occupy a wide range of elevations from 5-617 m (Fig. 8 , Fig. 9 ). Allocapnia are generally present at lower elevations, including Allocapnia recta and A. granulata , throughout the state (Fig. 9 ). The widest ranging elevations are reported for the most commonly collected species include A. minima , A. nivicola , and A. pygmaea (Fig. 9 ). The narrow range of reported elevations for A. ohioensis , A. zola , and A. illinoensis are due to the limited number of available records for each of these uncommon species (Fig. 9 ).

Figures

Figure 7. Adult flight period for 18 Capniidae species in New York State. Red fill indicates positive adult collections while gray shaded areas indicate adults are likely present but not yet reported.

Figure 8. Elevation box plot for stonefly families in New York State. Boxes indicate interquartile range, horizontal line in box represents median elevation, and outlliers are depicted with large circles.

Figure 9. Elevation box plot for 18 Capniidae species in New York State. Boxes indicate interquartile range, horizontal line in box represents median elevation, and outliers are depicted with large circles.