Blasticotomidae

Definition

A small family of sawflies (Hymenoptera) comprising 13 described species in 3 genera, restricted to temperate Eurasia. Larvae are specialized stem borers of ferns, an unusual host association within the Symphyta. Adults are seldom collected and the family is considered rare and poorly known.

Etymology

Example

Blasticotomidae larvae tunnel within the stipes and rachises of ferns such as *Matteuccia* and *Osmunda*, leaving diagnostic frass-filled galleries that can be detected by dissecting suspect stems.

Related Terms

• Symphyta
• Tenthredinidae
• sawfly
• stem borer
• fern herbivory

Usage Notes

Sometimes overlooked in regional surveys due to rarity and specialized fern-associated habitat; not to be confused with the similarly named but unrelated Blasticotomidae (a defunct family of beetles, now synonymized). The family is basal within the Tenthredinoidea but relationships remain tentative due to limited sampling.