Zorapterans: Order Zoraptera

Identification: Minute insects, 3 mm. or less. Tarsi 2-segmented. Antennae threadlike or beadlike, 9-segmented. Wings present or absent; if present, 4, membranous, FW a little larger than HW, and with few veins; wings eventually shed, leaving short stubs attached to thorax. Wingless forms without eyes, winged forms with compound eyes and 3 ocelli. Cerci short, 1-segmented, and terminating in a long bristle. Mouth parts chewing. Metamorphosis simple.

Similar orders: Isoptera, Psocoptera, Embioptera (pp. 88, 102, 100), and others: differ in form of tarsi, antennae, and cerci. Immature stages: Similar to adult but wings small or absent. Habits: Zorapterans are usually found under slabs of wood buried in piles of old sawdust, under bark, or in rotting logs; often occur in colonies. They feed chiefly on mites and other small arthropods. Zorapterans occur in the southeastern states from Maryland, Illinois, Arkansas, and Oklahoma south to Florida and Texas. They are not common. Importance: Not of economic importance.

Classification: One family, the Zorotypidae. No. of species: World, 22; N. America, 2.

Booklice and Barklice: Order Psocoptera

Identification: Small, soft-bodied, usually less than 5 mm. Wings present or absent, if present 4 in number, membranous, FW larger than HW, and held rooflike over body at rest; wing venation reduced. Face somewhat bulging. Ocelli present or absent. Antennae long and slender. Tarsi 2- or 3-segmented. Cerci absent. Mouth parts chewing. Metamorphosis simple. Similar orders: (1, 2) Mallophaga and Anoplura (pp. 106, 108): ectoparasites of birds and mammals; tarsi 1- or 2-segmented; antennae short. (3) Isoptera (p. 88): tarsi 4-segmented; antennae usually short; FW and HW of winged forms similar in size. (4) Zoraptera (p. 101): antennae 9-segmented; cerci present, 1-seg-mented. (5) Embioptera (p. 100): tarsi 3-segmented, basal segment of front tarsi greatly enlarged. (6) Small Neuroptera (p. 140): tarsi 5rsegmented.

Immature stages: Similar to adult but wings small or absent. Habits: Feed chiefly on dry organic matter, molds, or fungi. They occur in debris, under bark or stones, and on bark of trees; a few are found in buildings. Some species are gregarious and live in silken webs on trunks or branches of trees. Winged forms are commonly called barklice, and wingless forms booklice; most are active, fast-running insects.

Importance: Some species occasionally are pests in buildings, where they may damage books by feeding on starchy materials in bindings.

Classification: Three suborders and 11 families; suborders are separated by the characters of the antennae and labial palps, and families chiefly by characters of the legs, wings, and mouth parts. Some mouth-part characters cannot be seen in dried material and can be satisfactorily studied only in material preserved in alcohol or mounted on microscope slides. No. of species: World, 1100; N. America, 143.

Suborder Trogiomorpha

Antennae long and hairlike, with 20 or more segments. Labial palps 2-segmented. Tarsi 3-segmented.


Identification: Wings usually lacking or rudimentary, if well developed then FW broadly rounded apically. Body and wings without scales. Hind femora slender.

Trogiids most likely to be encountered are wingless forms

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