Pteronarcyidae

Judson, Sarah W. & Nelson, C. Riley, 2012, 3541, Zootaxa 3541, pp. 1-118 : 50-51

Pteronarcyidae

COMMON NAME: Salmonflies.

SIZE: Large (15–70 mm).

FEEDING GROUP: Shredders.

TOLERANCE VALUE: 0 (Low).

DIAGNOSIS: Adults of this family are the largest of all stoneflies inhabiting Mongolia. The wings have copious cross-veins to support the longitudinal veins during flight. Adults often are dark and often display orange or red intersegmental membranes, especially around the pronotum ( Fig. 355). Nymphs have finely branched gills on all thoracic segments ( Fig. 3) and the first two abdominal segments ( Fig. 4). Shriveled remnants of these gills persist in the adults.

DISCUSSION: The nymphs of these stoneflies are most commonly found in small but swiftly flowing streams among leaf packs and snags. The nymphs require 1–3 years to mature. Pteronarcyid nymphs can autohemorrhage by forcing hemolymph through pores in joints on the hind leg. This behavior is thought to cause a bad taste or serves to confuse predators. Only one genus, Pteronarcys , occurs in Mongolia. No generic diagnosis will be provided due to redundancy with family characteristics.