Giant

ROACHLIKE STONEFLIES Family Peltoperlidae

Identification: Brownish. 12-18 mm. FW with 10 or more costal cross veins, and without a forked vein rising from basal anal cell. Cerci short. 2 ocelli.

The common name refers to the roachlike appearance of the nymphs. The group is small, and chiefly northern and western. All the N. American species are in the genus Peltoperla, and only 2 of these occur in the East.

WINTER STONEFLIES Family Taeniopterygidae

Identification: Dark brown to blackish. Usually 15 mm. or less. Cerci short, 1- to 6-segmented. FW with a forked vein rising from basal anal cell. 2nd tarsal segment about as long as other tarsal segments.

Nymphs occur in large streams and rivers, and adults appear from January to April. Both nymphs and adults are plant feeders; adults sometimes feed on flowers.

ROLLED-WINGED STONEFLIES Family Leuctridae

Identification: Body appears very slender because wings at rest are bent down over sides of body. Generally 10 mm. or less. Cerci short, 1-segmented. FW with a forked vein rising from basal anal cell, and without a cross vein just behind costa in apical portion of wing; 2nd tarsal segment much shorter than other segments.

Leuctrids are brownish or blackish, and are most common in hilly or mountainous areas. Nymphs usually occur in small streams, and adults appear from December to June.

SPRING STONEFLIES Family Nemouridae Identification: Similar to Leuctridae but sometimes larger (to 15 mm.). FW flat at rest and with a cross vein just behind costa in apical portion of wing.

Nymphs are plant feeders and occur chiefly in small streams with sandy bottoms. Adults are brownish or blackish and appear from April to June. There are about 2 dozen N. American species, all in the genus Nemoura.

SMALL WINTER STONEFLIES Family Capniidae Identification: Length usually 10 mm. or less. Blackish. Cerci longer than greatest width of pronotum. 1st tarsal segment about as long as 3rd. Venation reduced. FW with few cross veins.

Nymphs usually occur in small streams, adults appear from November to April. Nymphs are plant feeders, and adults feed on blue-green algae. In some members of this group (species of Allocapnia) the anal lobe of hind wing is nearly as long as rest of the wing.

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