Acmaeodera knowltoni
Barr, 1969
Acmaeodera knowltoni is a metallic wood-boring beetle in the Buprestidae, first described by Barr in 1969. The occurs in western North America, with documented records from Utah and surrounding regions. are flower-visitors, frequently collected from blooms of Sphaeralcea, Penstemon, Rosa woodsii, and other flowering plants. The species is larger than the similar A. rubronotata, with uniformly orange rather than yellow elytral flecks with red towards the apices.
Pronunciation
How to pronounce Acmaeodera knowltoni: /ˌækmiːoʊˈdɛrə noʊlˈtoʊni/
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Identification
Acmaeodera knowltoni can be distinguished from the similar A. rubronotata by its larger size and uniformly orange elytral flecks (versus yellow flecks with red towards the apices in A. rubronotata). The is also larger than typical A. rubronotata individuals, making mature specimens relatively straightforward to identify in the field when both species occur together.
Images
Habitat
Pinyon-juniper woodland, Gambel oak woodland, and ponderosa pine forest at middle to higher elevations. are associated with flowering vegetation in these , particularly in areas with abundant Sphaeralcea, Penstemon, and Eriodictyon angustifolium. The has been collected from approximately 6000 feet elevation in canyon habitats with mixed conifer-oak vegetation.
Distribution
Western North America; documented from Utah (Washington County, Kane County), with records from Leeds Canyon and surrounding areas. The occurs in the Colorado Plateau region and associated mountain ranges.
Seasonality
active from late spring through summer; documented collections from late June through early July. Activity peaks during morning hours when temperatures warm and flowers are fully open.
Host Associations
- Sphaeralcea grossulariifolia - flower frequently collected from flowers
- Penstemon palmeri - flower collected from flowers
- Rosa woodsii - flower abundant on flowers in ponderosa pine/Gambel oak forest
- Eriodictyon angustifolium - flower collected from flowers
- Acmispon wrightii - flower collected from flowers
- Heliomeris multiflora - flower collected from flowers
- Opuntia aurea - flower pink form; collected from flowers
- Opuntia camanchica - flower collected from flowers
- Erythranthe guttata - flower collected from flowers near creek
- Erigeron flagellaris - flower collected from flowers
Behavior
are flower visitors, actively moving among blooming plants during warm morning hours. Individuals have been observed bedding down within partially closed cactus flowers for the evening. The shows strong association with specific flowering plants, with adults readily taking when disturbed from perches.
Similar Taxa
- Acmaeodera rubronotataSimilar size and appearance, but A. knowltoni is larger with uniformly orange elytral flecks versus yellow flecks with red markings in A. rubronotata
- Acmaeodera bowditchiSympatric flower-visiting frequently found on same plants; A. bowditchi has different elytral maculation pattern
- Acmaeodera diffusaFrequently co-occurs on same flowers; smaller size and different color pattern distinguish it from A. knowltoni
More Details
Nomenclatural history
Described by William F. Barr in 1969. The specific epithet honors Knowlton, presumably an individual associated with the specimen collection or study of the .
Field collection notes
In Leeds Canyon, Utah, the was found to be more abundant and individuals larger at higher elevations compared to lower canyon sites, facilitating easier distinction from A. rubronotata. The species was notably abundant on Rosa woodsii flowers in a recently burned ponderosa pine/Gambel oak forest area, where hundreds of Anthaxia caseyi and numerous A. knowltoni were collected from a single patch of blooming roses.