Oligoneuriidae

Definition

A family of mayflies (Ephemeroptera) with pantropical distribution, distinguished by nymphs bearing two rows of setae on the forelegs used for filter-feeding and tufted gills at the base of the maxillae. Adults are typically recognized by reduced mouthparts and relatively short cerci compared to other mayfly families.

Etymology

From Greek oligos (few, small) + neuron (nerve, sinew), referring to reduced wing venation characteristic of the family.

Example

Nymphs of Lachlania, a genus in Oligoneuriidae, use their brush-like forelegs to strain fine particulate organic matter from flowing water in tropical streams.

Synonyms

• brushlegged mayflies

Related Terms

• Ephemeroptera
• Mayfly
• filter-feeding
• nymph
• setae
• gill tufts
• pantropical distribution

Usage Notes

The common name "brushlegged mayflies" refers specifically to the diagnostic rows of setae on the forelegs of nymphs, a trait that separates them from other mayfly families. The family is most diverse in tropical regions and relatively uncommon in temperate faunas. Identification to family in the nymphal stage requires examination of leg setation and maxillary gill structure.