Bug FAQBlack Cactus Longhorn Beetle
Moneilema armatum · Order: Coleoptera · Family: Cerambycidae
Also called: Long-horned beetle
Source: Wikipedia
Black Cactus Longhorn Beetle is a flat-faced longhorn beetle in the Cerambycidae family.
Source: Wikipedia
How to recognize it
Black Cactus Longhorn Beetle is a flat-faced longhorn beetle in the Cerambycidae family.
Source: Wikipedia
Is it a pest in the house?
By boring into cactus stems and roots, they can damage prickly pear plants.
Source: Wikipedia
Where it comes from
Its native range is the southwestern United States and northern Mexico.
Source: Wikipedia
Where it is found in the US
Recorded in 5 of 51 states and DC. Most records: Texas, New Mexico, Oklahoma, Colorado, Arizona.
Darker = more records. Counts are museum and citizen-science records, not population size.
Source: GBIF
Months it is reported in the US
Source: GBIF
More photos
Questions people ask
How does this beetle affect my garden?
It bores into the stems and roots of prickly pear cactus, causing damage to the plants.
Source: Wikipedia
Same family (Cerambycidae)
House LonghornHylotrupes bajulusCan damage your home
Asian Longhorned BeetleAnoplophora glabripennisDamages trees, gardens or crops
Red Milkweed BeetleTetraopes tetrophthalmus
White-spotted SawyerMonochamus scutellatusCan damage your home
Red Pine Longhorn BeetleStictoleptura rubra
Spotted Longhorn BeetleRutpela maculataSources
- Wikipedia: https://en.wikipedia.org/wiki/Moneilema_armatum
Look it up elsewhere: GBIF · iNaturalist · BugGuide · ITIS · Wikipedia
Text written 2026-10-26 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-26.