Snakeflies

Definition

A relict order of predatory holometabolous insects (Raphidioptera) characterized by an elongate prothorax that gives the appearance of a snake-like 'neck,' large transparent wings with dense venation, and an elongate ovipositor. Adults and larvae are both active predators on soft-bodied arthropods. The group comprises two extant families—Raphidiidae and Inocelliidae—with roughly 260 species, now restricted to temperate regions of the Northern Hemisphere after a broader distribution and greater diversity during the Mesozoic.

Etymology

From the snake-like appearance of the elongate prothorax; order name Raphidioptera from Greek rhaphís (needle) + pterón (wing), referring to the slender body and wing structure.

Example

The square-headed snakefly genus Agulla (family Raphidiidae) is commonly found in western North American forests, where adults hunt aphids and small caterpillars among conifer foliage.

Synonyms

• Raphidioptera

Related Terms

• Neuropterida
• Raphidiidae
• Inocelliidae
• prothorax
• holometabolous
• relict distribution
• Lacewings
• Antlions

Usage Notes

Snakeflies are one of the four orders traditionally grouped as Neuropterida, alongside lacewings, antlions, and alderflies. The elongate prothorax distinguishes them superficially from similar neuropteroid insects. The absence of snakeflies from tropical and Southern Hemisphere regions reflects their relict status and climatic constraints on their distribution. Larvae are found under bark or in leaf litter, not in aquatic habitats like some related neuropteran larvae.