Entity scope
This profile covers Anasa tristis. Related leaf-footed bugs and stink bugs require comparison.
Quick identity
- Scientific scope
- Anasa tristis
- Entity scope
- Species profile
- Broad form
- Flattened gray-brown adult true bug; nymphs are pale to gray with dark legs.
- Useful clue
- Bronze eggs commonly occur in orderly clusters on leaf undersides near veins.
- Typical context
- Squash, pumpkins, gourds, and related cucurbits.
- Identification limit
- One organism, symptom, or photograph is not enough for reliable species certainty.
Key characteristics
- Flattened gray-brown adult true bug; nymphs are pale to gray with dark legs.
- Bronze eggs commonly occur in orderly clusters on leaf undersides near veins.
- Host and habitat context matter: Squash, pumpkins, gourds, and related cucurbits.
- Color, size, and plant injury can overlap with unrelated organisms; preserve uncertainty when views are incomplete.
Life stages
01
Egg and nymph
Bronze clusters hatch into pale nymphs that darken.
02
Adult
Flattened gray-brown overwintering stage.
Where it is found
- Squash, pumpkins, gourds, and related cucurbits.
- Nymphs and adults pierce plant tissue and shelter near stems, leaves, or debris.
- Regional range and seasonal timing affect which species are plausible.
Behavior and activity
- Nymphs and adults pierce plant tissue and shelter near stems, leaves, or debris.
- Visible abundance can change with weather, plant condition, natural enemies, and life stage.
- Plant damage without the organism present does not establish the cause.
Diet and resources
- Plant or habitat relationship: Squash, pumpkins, gourds, and related cucurbits.
- Resource use varies within broad groups and should not be generalized beyond this entity scope.
Associated signs
Yellow-brown spotting, wilting, and clusters on cucurbits support feeding but wilt has other causes. These signs also have other pest and non-pest explanations.
Common lookalikes
Often more shield-shaped on wider host ranges.
May have expanded hind legs and different eggs.
Larvae tunnel inside stems with different frass.
Why it matters
Identity and impact are separate questions
Heavy feeding can injure cucurbits, especially young plants, but one adult or old egg cluster does not predict outcome.
- Do not infer the responsible species from damage alone.
- Assess current activity, affected area, plant health, and change over time before deciding whether action is warranted.
Management direction
- Confirm the insect and current eggs or nymphs.
- Separate sap feeding from borer, disease, and water stress.
- Use cucurbit-specific IPM after assessing stage and abundance.
Have a pest photo to check?
Start a new photo identification. This Profile gives comparison context; it does not transfer certainty or diagnose your image.
Identify a photoReviewed guidance and sources
Last reviewed August 2026. Sources support the claims listed with them; their limits remain part of the review.
- University of Minnesota Extension — Squash bugs
Supports: Adult, egg, nymph traits, hosts, feeding, and lifecycle.
Does not support: Cause of wilt from symptoms alone.
Scope note: North American garden and landscape context; species, hosts, seasons, and local guidance vary.
- University of Minnesota Extension — Common insects in vegetable crops
Supports: Host crops, life-cycle context, damage patterns, scouting, and IPM context.
Does not support: Species certainty from damage alone or a universal pesticide program.
Scope note: North American garden and landscape context; species, hosts, seasons, and local guidance vary.