Ripiphorus walshii

Distinguished from other Ripiphorus species by male genitalic characters and subtle differences in antennal structure. The combination of wedge-shaped body, abbreviated elytra, and association with particular host insects aids in generic identification. Males can be separated from females by their more elaborate antennae.

Adults have an elongated, wedge-shaped body form characteristic of the genus Ripiphorus. The body is somewhat flattened and tapers posteriorly. Antennae are serrate or pectinate in males. The elytra are abbreviated, exposing several abdominal tergites. Coloration is generally dark with possible reddish or yellowish markings, though specific details for this species are not well documented.

Adults are found in open, sunny areas where their host insects occur. The species has been recorded from Ontario, Canada, suggesting a temperate North American distribution. Specific microhabitat preferences for this species are not well documented.

Recorded from North America, specifically Ontario, Canada. The broader range likely extends into the northern United States, though precise distribution records are sparse.

Adults have been observed in summer months (July-August), consistent with the seasonal activity pattern of many Ripiphorus species.

• Hymenoptera (bees or wasps) - parasitoidRipiphorus species are known to parasitize the larvae of bees or wasps; specific host records for R. walshii are not confirmed but are inferred from genus-level biology

Undergoes hypermetamorphosis, a complex form of complete metamorphosis involving multiple larval forms. The first-instar larva (planidium) is mobile and seeks out host insects. Subsequent larval instars are grub-like and feed internally on the host. Pupation occurs within the host cell or in the soil.

Adults are diurnal and active in warm, sunny conditions. They are weak fliers compared to many beetles. Males use their modified antennae to detect female pheromones.

Acts as a parasitoid of Hymenoptera, potentially influencing host population dynamics. The ecological impact is likely limited due to low population densities typical of Ripiphoridae.

No direct economic importance. Occasionally encountered by entomologists and naturalists. Not a pest of agriculture or forestry.

• Ripiphorus speciesOther members of the genus share the wedge-shaped body and abbreviated elytra; species-level identification requires examination of male genitalia and antennal structure
• Other Ripiphoridae generaPelecotoma and Macrosiagon have different body proportions and antennal forms; Pelecotoma has more strongly pectinate antennae in males

• Ripiphoridae
• parasitoid
• hypermetamorphosis
• Coleoptera
• North America

• BugGuide
• GBIF taxonomy match
• iNaturalist taxon
• An Old Flame (Skimmer) | Bug Squad