Bug FAQProtohermes grandis
Protohermes grandis · Order: Megaloptera · Family: Corydalidae
Protohermes grandis adults are 36 to 40 mm long, have a skinny body, four large wings, and are light yellow-brown with yellow spots on the wings. They live across many habitats, from streams to forests and mountains, while their larvae develop in clear water and may stay for 1 to 3 years before emerging as short-lived adults that fly at night.
Source: Wikipedia
How to recognize it
The body is light yellow-brown and the wings have yellow spots.
Source: Wikipedia
Size
Adults measure about 36 to 40 mm in length and have a slender body with four large wings.
Source: Wikipedia
Where it lives
Adults are found in streams, flatlands, forests and mountains. Larvae live in clear water such as streams.
Source: Wikipedia
What it eats
Adults feed on nectar from Japanese chestnut flowers, usually at night. Larvae eat larger prey and tend to avoid smaller prey as they grow.
Source: Wikipedia
Life cycle
The larval stage lasts about one to three years, while the adult stage lasts only four to seven days. The length of each stage varies with the type of aquatic environment they inhabit.
Source: Wikipedia
Lookalikes
They are closely related to Protohermes immaculatus.
Source: Wikipedia
More photos
Questions people ask
What do adult Protohermes grandis eat?
Adults feed on nectar from Japanese chestnut flowers, usually at night.
Source: Wikipedia
Same family (Corydalidae)
Sources
- Wikipedia: https://en.wikipedia.org/wiki/Protohermes_grandis
Look it up elsewhere: GBIF · iNaturalist · BugGuide · Wikipedia
Text written 2026-10-23 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-23.