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Taxonomy

See also list of butterflies and moths.

processionary caterpillar, (genus Thaumetopoea), small genus of moths, the larval stage of which is known for marching in single file columns to their food source. These hairy caterpillars live in communal webs and march in columns to their food source. During the movement each larva lays down a silken thread. The large adults have dull-colored wings and lack a proboscis (feeding organ). Females possess an abdominal hair tuft, which is used to cover the egg masses.

Other processionary caterpillars

Certain other members of the subfamily Thaumetopoeinae are known for having processionary caterpillars. The larvae of the Australian bag-shelter moth (Ochrogaster lunifer), for example, emerge from their communal silken nest to form long processions to food sources. Similarly, the caterpillars of the reticulate bagnest moth (Anaphe reticulata) of southern Africa are known to form single file processions. 

The Editors of Encyclopaedia BritannicaThis article was most recently revised and updated by Melissa Petruzzello.