# Fiery searcher (Calosoma scrutator) > A large, metallic ground beetle that climbs vegetation to hunt caterpillars and other insects; beneficial to gardens and forests. Source: https://insectscanner.com/species/fiery-searcher/ (updated 2026-10-10) ## Is it dangerous? **Non-toxic.** Not dangerous to people. Adults can deliver a defensive spray or secretion if handled that may be unpleasant and could mildly irritate sensitive skin or eyes; they do not have a venomous bite. Handle with care or avoid handling. **Pets:** Not toxic to pets. Large beetles can pinch gently with their mandibles if provoked but generally do not pose a serious risk to cats or dogs. ## Quick facts - Scientific name: Calosoma scrutator - Also called: Searcher beetle, Caterpillar hunter - Order: Coleoptera (Beetles) - Family: Carabidae (Ground beetles) - Size: 25-35 mm body length - Colours: Metallic green, Bronze, Reddish-orange - Habitat: Forests, orchards, gardens, fields; often found on tree trunks, shrubs and low vegetation as well as on the ground under debris. - Range: Native to much of North America (southern Canada through the United States). - Active: Spring through fall; diurnal and nocturnal activity, often most active at night but also climbs vegetation during the day to hunt. - Lifespan: Adults can live for more than one year (up to several years in related Calosoma species), overwintering in the soil or sheltered ground sites. - Effect on plants: Pest predator - Pest: no ## Overview Calosoma scrutator is a species of ground beetle (family Carabidae) known for its active predation on caterpillars and other soft-bodied insects. Adults are strong runners and climbers; they often ascend trees and shrubs when hunting. They are considered beneficial predators in forests, orchards and gardens because they reduce populations of defoliating caterpillars. This species is native to much of North America and is most often encountered from spring through fall. ## How to identify it Adults are relatively large, elongate and somewhat flattened for a ground beetle, with metallic, shiny elytra and a distinctive sheen on the head and thorax. The elytra (wing covers) typically show iridescent colors that can include green, bronze and areas of red or orange along the margins or apex on some individuals. Legs and antennae are long and adapted for running. The surface of the elytra is finely grooved or punctate (textured) rather than smooth. - Large, elongate ground beetle 20-35 mm long with metallic, iridescent elytra - Elytra often show green or bronze tones with reddish-orange margins or apex on some individuals - Pronotum (thorax) narrower than elytra and glossy; elytra finely grooved or punctate rather than smooth - Often found climbing tree trunks and foliage when hunting caterpillars (behavioral clue) ## Lookalikes - **Forest caterpillar hunter** (Calosoma sycophanta): Similar size and shape but the elytra are uniformly golden-green without the coppery-red margins; introduced to North America from Europe to control the spongy moth. - **Fiery hunter** (Calosoma calidum): Black elytra with rows of coppery-red or golden pits instead of metallic green; mainly hunts on the ground rather than climbing trees. ## Life cycle - **Egg:** Females lay eggs in soil or litter near where caterpillar prey are available. - **Larva (grub):** Larvae are active predators in the soil or on vegetation, feeding on caterpillars and other insect larvae. - **Pupa:** Larvae pupate in the soil, undergoing transformation to the adult form. - **Adult (beetle):** Adults are active hunters that search vegetation and ground litter for prey; they may overwinter as adults. ## Diet and predators - Young eat: Predatory: caterpillars and other insect larvae - Adults eat: Predatory: caterpillars, moth larvae and other soft-bodied insects; adults may also scavenge - Predators of the young: Ground-foraging birds, predatory insects, spiders - Predators of adults: Birds, small mammals, larger predatory insects and spiders ## Effect on plants and gardens Adults and larvae feed on caterpillars and other insect pests, so they help protect trees, shrubs and garden plants from defoliation. ## Where and when to find it Look on tree trunks, shrubs and low vegetation for adults; check leaf litter and soil for larvae and pupae. Adults may also be seen on the ground at night. - Best time: Spring through fall; evenings and nights can be good for observing active adults, but they also climb vegetation during the day. - Tips: Use a long lens or phone camera when photographing on tree trunks to avoid disturbing the beetle. Check areas with caterpillar activity; shining a flashlight at night can reveal active hunters. ## Fun facts - Fiery searchers will climb trees and shrubs to hunt caterpillars rather than staying only on the ground. - Because they eat caterpillars that defoliate trees, they are considered helpful natural pest control in forests and gardens. ## Frequently asked questions ### Are fiery searcher beetles harmful to humans? No. They are not venomous. They can produce an unpleasant defensive secretion and may nip if handled, so avoid touching them with bare hands. ### Do fiery searchers bite or sting? They do not sting. They can bite with mandibles if provoked, but bites are not venomous and rarely break the skin. ### Why is a fiery searcher on my tree or in my garden? They climb trees and vegetation to hunt caterpillars and other insect prey. If you have caterpillars nearby, fiery searchers are likely searching for food. ### How can I get rid of fiery searcher beetles? They are beneficial predators, so removal is usually unnecessary. If you must relocate one, gently coax it into a container and release it outdoors away from people. Avoid pesticides that kill beneficial insects. ### Where does the fiery searcher live? In North America it lives in forests, orchards, fields and gardens, spending time on tree trunks, shrubs and ground litter where prey are available. --- More about this species: [iNaturalist](https://www.inaturalist.org/taxa/118855), [Wikipedia](https://en.wikipedia.org/wiki/Calosoma_scrutator). Identify insects and spiders from a photo with the Insect Scanner iPhone app: https://apps.apple.com/app/id1543946563?pt=126685406&ct=web-markdown&mt=8 Identification from photos is never certain: don't handle insects you can't identify, and get medical advice for bites, stings or allergic reactions.