Pristiphora rufipes

Adults are distinguished from flies by having two pairs of wings rather than one. From other small wasps, they are recognized by their association with columbine plants and their small size. Larvae are distinguished from caterpillars (Lepidoptera larvae) by counting prolegs: sawfly larvae have six or more pairs, while caterpillars have five or fewer. Additionally, sawfly larvae lack crochets on their prolegs. The black head capsule of the larva is distinctive. Close examination of leaf damage and the presence of eggs inserted into slits in leaf tissue can confirm identification.

Found in gardens, landscapes, and natural areas where columbine plants (Aquilegia spp.) grow. Adults are often observed flying around or resting on columbine foliage. Larval development occurs on columbine leaves. The species thrives in temperate climates with sufficient moisture for host plant growth. In North America, established populations occur in suburban gardens, parks, and woodland edges where columbines are cultivated or naturalized.

Native to central Europe. Introduced to North America: first recorded in Canada in 1963, reached upstate New York by 1983. Current range extends from the eastern seaboard of the United States westward to the Rocky Mountains. Distribution records include Canada (Alberta, British Columbia, Manitoba, Newfoundland) and widespread across the northern and eastern United States. Present in England with established populations.

Activity begins in spring when columbine foliage emerges. In the mid-Atlantic region of the United States, adults appear with the first new growth of columbines, typically April to May. Two generations occur per year in this region, with a second generation active in early summer. In England, three or more generations may occur annually. Northern states and Canada report a single generation. Pupae overwinter in soil, with adult emergence timed to host plant phenology.

Adults feed on nectar, pollen, and other small insects. Larvae are obligate feeders on columbine (Aquilegia spp.) leaves, consuming leaf tissue from the margins inward. Heavy infestations can result in complete defoliation of host plants.

• Aquilegia - primary host plantLarval food source; adults oviposit into leaves

Females use a saw-like ovipositor to cut slits in columbine leaves and insert eggs. Eggs hatch in approximately 1-2 weeks. Larvae feed on leaf tissue for 2-3 weeks, progressing through several instars. Mature larvae drop to the ground and spin brown cocoons in soil or leaf litter. Pupation occurs within the cocoon. Duration of pupal stage varies by region: single generation in northern areas, with adults emerging the following spring; multiple generations possible in warmer climates where adults may emerge within the same season or overwinter as pupae.

Females are active during daylight, flying among columbine plants to locate suitable oviposition sites. When laying eggs, females make precise cuts in leaf epidermis with their ovipositor. Larvae feed gregariously when young, dispersing as they grow larger. When disturbed, larvae may drop from leaves on silken threads. Mature larvae actively seek soil to burrow and pupate. Adults are not aggressive and do not sting humans.

As a non-native herbivore, P. rufipes functions as a folivore on columbine plants, capable of significant population-level damage to ornamental and native columbine stands. The species serves as prey for generalist insectivores including birds, which may consume larvae. It contributes to nutrient cycling through herbivory and subsequent plant tissue decomposition. No documented role as pollinator despite adult nectar feeding.

Significant pest of ornamental columbines in gardens and landscapes. Economic impact primarily aesthetic, as heavy defoliation reduces plant appearance though plants often recover. Management includes hand-picking larvae, biological control through bird predation, and application of OMRI-listed insecticides for severe infestations. Educational value in distinguishing sawfly larvae from caterpillars. Not a threat to human health—adults lack stingers despite wasp-like appearance.

• Macremphytus tarsatusDogwood sawfly larvae also have black heads and resemble columbine sawfly larvae, but feed on dogwood (Cornus spp.) rather than columbine. Adult morphology differs, with dogwood sawfly adults having distinct color patterns.
• Atomacera deceptaMallow sawfly is similar in size and biology but feeds on hibiscus and mallow plants. Adults differ in coloration, typically with more contrasting patterns.
• Lepidoptera larvaeCaterpillars of moths and butterflies resemble sawfly larvae in general body form but can be distinguished by proleg number (5 or fewer pairs vs. 6+ in sawflies) and presence of crochets on prolegs in caterpillars.
• Phytomyza aquilegivoraColumbine leafminer is a fly whose larvae mine inside columbine leaves rather than feeding externally. Damage appears as winding trails or blotches within leaf tissue, not marginal chewing.

Often mistaken for flies due to small size and dark coloration; however, the four wings (two pairs) distinguish sawflies from true flies (one pair). Frequently confused with stinging wasps, but sawflies lack a stinger and are harmless to humans. Larvae are often mistaken for caterpillars and may be overlooked by gardeners familiar with Lepidoptera pests; the different proleg count is a reliable distinguishing feature.

• sawfly
• columbine
• garden pest
• defoliator
• non-native
• hymenoptera
• ornamental pest
• invasive insect

• BugGuide
• GBIF taxonomy match
• iNaturalist taxon
• NCBI Taxonomy
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