Nymphidae

Adults can be distinguished from other Myrmeleontoidea by the divided or split tarsal structure that gives the family its common name. They differ from antlions (Myrmeleontidae) in adult morphology and from owlflies (Ascalaphidae) by the absence of the large divided eyes characteristic of that family. Larval identification is straightforward: elongate, debris-camouflaged ground-dwelling larvae indicate Nymphinae, while broad, disc-shaped, plant-dwelling larvae indicate Myiodactylinae. The restricted geographic range (Australia and New Guinea) aids in field identification.

Adults possess the general neuropteran body plan with two pairs of membranous, similarly sized wings with dense venation. The common name "split-footed lacewings" refers to a characteristic division of the tarsi (foot segments). Wing patterns and body size vary among the 35 extant species. Larvae exhibit pronounced morphological divergence between subfamilies: Nymphinae larvae have elongate, slender bodies resembling antlion larvae, while Myiodactylinae larvae possess broad, disc-shaped, dorsoventrally flattened bodies adapted for arboreal life.

Nymphinae larvae inhabit ground-level environments where they construct debris camouflage and hunt in leaf litter or soil. Myiodactylinae larvae are strictly arboreal, living on vegetation surfaces. Adult habitat preferences are poorly documented but are presumably associated with the vegetation types supporting their larval prey. The family shows no particular association with aquatic or riparian habitats unlike some other neuropteran families.

Extant species are restricted to Australia and New Guinea. Fossil genera demonstrate a formerly broader distribution encompassing Europe, Asia, North America, and South America during the Mesozoic and early Cenozoic eras.

Adults are predaceous. Larvae of both subfamilies are active predators: Nymphinae larvae hunt on the ground using pitfall or ambush tactics similar to antlions, while Myiodactylinae larvae forage on vegetation surfaces.

Complete metamorphosis with egg, larva, pupa, and adult stages. Larval ecology diverges sharply between subfamilies: Nymphinae larvae are terrestrial with elongate bodies and debris camouflage; Myiodactylinae larvae are arboreal with disc-shaped bodies. Specific details of egg deposition, pupation sites, and developmental duration are not well documented.

Adults are primarily nocturnal and attracted to light sources. Nymphinae larvae actively hunt or ambush prey on the ground surface. Myiodactylinae larvae forage on plants using their flattened body form. No documentation of adult feeding behavior, mating rituals, or defensive behaviors is available.

Predatory insects at both larval and adult stages, contributing to arthropod population regulation in Australian and New Guinean ecosystems. Nymphinae larvae function as ground-dwelling predators in detrital food webs; Myiodactylinae larvae serve as foliage predators.

No documented economic importance. Adults occasionally attracted to artificial lights. No known use in biological control or cultural significance.

• Myrmeleontidae (antlions)Adult Nymphidae were historically confused with antlions; distinguished by split tarsi and different wing venation patterns. Nymphinae larvae resemble antlion larvae in body form but differ in mandible structure and habitat specificity.
• Ascalaphidae (owlflies)Shared nocturnal habits and general neuropteran appearance; distinguished by divided eyes in owlflies versus split tarsi in Nymphidae.
• Nemopteridae (spoonwings)Formerly considered closely related based on morphological similarities; molecular and refined morphological analysis places spoonwings in a separate lineage of Myrmeleontiformia.

• BugGuide
• Wikipedia
• GBIF taxonomy match
• iNaturalist taxon
• NCBI Taxonomy
• Catalogue of Life