Trumpetnet and Tubemaking Caddisflies

Family Psychomyiidae

Identification: Mesoscutum with a pair of small warts. 5th segment of maxillary palps with faint cross striations.

This is a large and widely distributed group of small caddis-

NET-SPINNING CADDISFLIES, ETC. 215

flies, mostly brownish and 4-11 mm. Larvae occur in a variety of aquatic habitats. Some larvae construct a trumpet-shaped net, usually in running water; others burrow into the sand at the bottom of streams and cement the walls of the burrow to form a fairly rigid tube.

NET-SPINNING CADDISFLIES Family Hydropsychidae Identification : Mesoscutum without warts.

Adults of this group are found along streams. They are widely distributed and fairly common. Larvae construct a cup-shaped net, with the open side facing upstream, and spend most of their time in a retreat near the net.

MOLANNIDS Family Molannidae Identification : Middle femora with a row of 6-10 spines.

Our 5 species of molannids occur east of the Rocky Mts. from s. Canada south to Oklahoma, Illinois, and Pennsylvania. Adults are 10-15 mm. Larvae occur in streams with a sandy bottom; their cases are cylindrical tubes of sand grains, with lateral expansions.

CAL AM O CERATID S Family Calamoceratidae p. 217

Identification : Scutellum small, rectangular, without warts;

mesoscutal warts represented by 2 rows of small bristly spots extending length of scutum. Maxillary palps 5- or 6-segmented.

Two of the 5 U.S. species of calamoceratids occur in the eastern states, and 3 occur in the West (Arizona, California, Alaska). They are relatively rare. The larva of 1 eastern species makes its case in a hollowed-out twig.

ODONTOCERIDS Family Odontoceridae Identification: Scutellum large and domelike, with a single wart occupying most of sclerite. Tibial spurs not hairy.

Ten rather rare species of odontocerids occur in N. America, 5 in the East and 5 in the West. The known larvae occur in riffles of streams and make cylindrical, slightly curved cases of sand grains.

GOERIDS Family Goeridae Not illus.

Identification: Scutellum with a single elongate wart occupying only central part of sclerite. Tibial spurs hairy. Maxillary palps 3-segmented in c? and 5-segmented in 9 .

This is a small group of rather rare caddisflies, most of them restricted to the East. Three N. American species have been reared; their larvae occur in streams and make cylindrical cases of sand grains and small pebbles, with 1 or 2 larger pebbles glued to each side.

LEPID O STO MATID S Family Lepidostomatidae

Identification: Scutellum with a pair of warts. Maxillary palps 1- or 3-segmented in c? and 5-segmented in 9 . Preapical tibial spurs long, hairy, located about middle of tibia.

This group is widely distributed but its members are not common. Larvae usually occur in streams or springs; their cases are often square in cross section. Males of some species have rather bizarre characters, such as peculiarly modified maxillary palps, leaflike legs, or widened wings.

BRACHYCENTRID S Family Brachycentridae

Identification: Scutellum with a pair of warts. Maxillary palps 3-segmented in cF and 5-segmented in 9. Middle tibiae with or without apical spurs. Mesoscutum with a pair of small, widely separated warts.

Brachycentrids are 6-11 mm. and occur along streams. Larval cases are elongate, either round or square in cross section, and are made* of sand or bits of vegetable material. Young larvae of some species live near shore, whereas older larvae move to midstream and attach their cases to stones.

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