Large leaf beetle with bright orange elytra marked by black spots or stripes; pronotum black with orange margins. Distinguished from similar orange-and-black milkweed insects by hardened forewings (elytra) characteristic of beetles, versus membranous wings of true bugs or scaled wings of butterflies. Larger and more robust than red milkweed beetles (Tetraopes spp.), which have elongated bodies and black antennae.

Associated with milkweed plants, particularly swamp milkweed (Asclepias incarnata) and common milkweed (A. syriaca). Found in meadows, marshes, and wetlands where host plants grow. Preference for swamp milkweed may reflect adaptive avoidance of ground-dispersing predation due to water surrounding plant bases.

North America, including United States and Canada (Alberta). Present in Middle America.

Adults active from mid-summer through autumn. Reproduction ceases and diapause initiates under short-day photoperiods (≤12 hours light). Fresh adults emerge in September, feed, then seek protected overwintering sites. Multiple generations possible in favorable years with long growing seasons.

Specialized herbivore feeding on milkweed leaves (Asclepias spp.), including swamp milkweed (A. incarnata), common milkweed (A. syriaca), butterfly weed (A. tuberosa), and occasionally related genera such as Cynanchum and Funastrum (family Apocynaceae). Adults and larvae consume leaf tissue, creating large notches and holes.

• Asclepias incarnata - primary host plantPreferred for oviposition; swamp habitat may protect larvae from ground-dispersing predators
• Asclepias syriaca - host plantCommon milkweed; abundant host in many areas
• Asclepias tuberosa - host plantButterfly weed; used in perennial gardens
• Cynanchum - occasional hostSwallow-wort genus
• Funastrum - occasional hostTwinevine genus
• Chrysomelobia labidomerae - parasiteSubelytral mite transmitted during copulation; reduces survival of nutritionally stressed beetles

Eggs deposited on undersides of milkweed leaves. Larvae hatch and feed on foliage; neonates occasionally cannibalize unhatched siblings. Larvae drop to soil to pupate. Adults emerge, feed, and reproduce; photoperiod determines whether reproduction continues or diapause ensues. Overwintering occurs in adult stage in protected refugia.

Adults are active walkers, reluctant to settle. Females lay orange, jellybean-shaped eggs in batches on leaf undersides. Copulation lasts approximately 3.5 hours on average. Males engage in mate guarding and male-male competition for access to females; larger males achieve higher mating success. Parasitized males may increase reproductive effort, contacting rival males more frequently and displacing them from females. Cannibalism occurs among neonate larvae.

Herbivore that consumes milkweed foliage; part of milkweed-associated food web. Sequesters cardiac glycosides from host plants, contributing to aposematic defense system shared with co-occurring milkweed specialists. Serves as host for sexually transmitted mites and nematodes. High larval mortality from predation may limit population density.

Occasionally considered a pest of ornamental milkweeds in gardens. May compete with monarch butterflies for milkweed foliage; adult beetles can displace small monarch caterpillars from feeding sites. Subject of research on chemical ecology, mimicry, and sexually transmitted parasites.

• Tetraopes tetraophthalmusRed milkweed beetle; also orange and black, milkweed-associated, but with elongated body, black antennae, and eyes divided by antennae insertion
• Oncopeltus fasciatusLarge milkweed bug; similar orange and black warning coloration and milkweed association, but true bug with membranous wings and long beak for seed feeding
• Danaus plexippusMonarch butterfly; shares Müllerian mimicry complex and milkweed host association, but lepidopteran with scaled wings and larval stage as caterpillar

• leaf beetle
• milkweed
• aposematic coloration
• Müllerian mimicry
• chemical defense
• cardenolide sequestration
• photoperiodism
• sexually transmitted parasite
• cannibalism
• predation mortality
• swamp milkweed
• common milkweed
• Chrysomelidae
• herbivore
• diapause
• Kirby 1837

• BugGuide
• GBIF taxonomy match
• iNaturalist taxon
• NCBI Taxonomy
• Hey beetles, leave some milkweed for the monarchs: Milkweed leaf beetle, Labidomera clivicollis — Bug of the Week
• Kentucky | Beetles In The Bush
• Orange and Black II: Milkweed leaf beetle, Labidomera clivicollis; Oleander aphid, Aphis nerii; Milkweed Bug, Oncopeltus fasciatus; Monarch, Danaus plexippus — Bug of the Week
• Orange and Black Bugs- Milkweed leaf beetle, Labidomera clivicollis; Oleander aphid, Aphis nerii; Milkweed Bug - Oncopeltus fasciatus; Monarch butterfly, Danaus plexippus — Bug of the Week
• Photoperiodic effect on size‐related metamorphosis in the milkweed leaf beetle, Labidomera clivicollis
• Sexually transmitted parasites and sexual selection in the milkweed leaf beetle, Labidomera clivicollis
• Photoperiodic control of reproduction in the milkweed leaf beetle, Labidomera clivicollis
• Effects of parasitism by the miteChrysomelobia labidomerae(Acari: podapolipidae) on the longevity and fecundity of its host beetle,labidomera clivicollis(coleoptera: chrysomelidae)
• Population Dynamics of a Relatively Rare Species of Milkweed Beetle (Labidomera)