Longhorned Earwig

LONG-HORNED EARWIGS Family Labiduridae

Identification: Second tarsal segment cylindrical and not prolonged distally beneath 3rd segment. Antennae 16- to 30-segmented; segments 4-6 together rarely longer than 1st segment. Wings present or absent.

A common wingless species in this group is the Seaside Earwig, Anisolabis maritima (Géné), which occurs along Atlantic and Pacific Coasts; it is. 18-20 mm. and has 24-segmented antennae. A common winged labidurid is the Striped Earwig, Labidura bidens (Olivier), 13-20 mm., found in the eastern states. The wingless labidurids (Anisolabis and Euborellia), which have the male cerci asymmetrical (the right one more curved), are sometimes placed in a separate family, the Psalididae.

LITTLE EARWIGS Family Labiidae Identification: Tarsi as in Labiduridae. Antennae 11- to 15-segmented; segments 4-6 together longer than 1st segment. Wings usually present. Generally 4-7 mm.

The most common little earwig is Labia minor (Linn.), which is 4-5 mm. and light brown; it has been introduced into this country from Europe. The Handsome Earwig, Prolabia pul-chella (Serville), 6.0-6.5 mm. and dark brown, is fairly common in the southern states.

Webspinners: Order Embioptera

Identification: Small (mostly 4-7 mm.), slender-bodied, usually yellowish or brownish. Tarsi 3-segmented, basal segment of front tarsi greatly enlarged. Legs short, hind femora thickened. Antennae short, threadlike, 16- to 32-segmented. Ocelli absent. Wings present or absent in cf and always absent in 9 ; 4 wings when present are membranous, HW slightly smaller than FW, and venation weak, each vein in the middle of a brown band; wings at rest held flat over body. Cerci present, 1- or 2-segmented, usually asymmetrical in cf and always so in 9 . Mouth parts chewing. Metamorphosis simple. Similar orders: (1, 2, 3) Isoptera, Zoraptera, and Psocoptera (pp. 88, 101, 102): basal segment of front tarsi not enlarged; Isoptera have 4-segmented tarsi, and their galleries are not silk-lined; Zoraptera have 2-segmented tarsi and 9-segmented antennae; Psocoptera have 2- or 3-segmented tarsi, and lack cerci. Immature stages: Similar to adult but wings small or absent. Habits: Webspinners live in colonies in silk-lined galleries in soil or debris and among mosses or lichens. Silk is spun from glands in basal segment of front tarsi; both adults and nymphs have silk glands. These insects are active and run rapidly, usually backward; sometimes play dead when disturbed. They feed chiefly on dead plant materials. The eggs are laid in the galleries and are often covered with chewed food particles; eggs are attended by the females. Both winged and wingless males occur in some species. Webspinners are not common, and are restricted to the southern states.

Importance: Not of economic importance.

Classification: Three families in N. America, which differ in wing venation and in the character of cerci and mandibles. No. of species: World, 149; N. America, 9.

Key to Families

1. R4+5 in wings of cf forked; left cercus 2-segmented; Gulf

Coast, Florida to s. Texas Teratembiidae

1'. R4-(-5 in wings of cf not forked; if wings are absent, left cercus is 1-segmented 2

2. Mandibles without apical teeth; 10th tergum of cf com pletely divided by a median membranous area that reaches 9th tergum; left cercus of cf usually with peglike spines on inner side of basal segment; lower Mississippi Valley and Southwest Anisembiidae

2'. Mandibles with distinct apical teeth; 10th tergum of cf incompletely divided by a median membranous area that does not reach 9th tergum; left cercus of cf smooth on inner side; southern states Oligotomidae

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