Anthidium oblongatum

(Illiger, 1806)

oblong woolcarder bee

Anthidium oblongatum is a solitary in the Megachilidae, commonly known as the oblong woolcarder bee. Native to Eurasia and North Africa, it has been introduced to North America and South America, with a first record in central Chile documented in 2025. Females construct nests using plant fibers collected from leaves, earning the 'woolcarder' . The shows strong floral specialization, primarily foraging on Fabaceae, Crassulaceae, and Resedaceae.

Anthidium oblongatum by (c) Michelle Orcutt, some rights reserved (CC BY), uploaded by Michelle Orcutt. Used under a CC-BY license.

Anthidium oblongatum by (c) Bernie Paquette, some rights reserved (CC BY), uploaded by Bernie Paquette. Used under a CC-BY license.

Pronunciation

How to pronounce Anthidium oblongatum: //ænˈθɪdiəm ˌɒblɒŋˈɡætəm//

These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.

Identification

Distinguished from the related European woolcarder (Anthidium manicatum) by its more slender, oblong body shape and less robust build. The specific epithet 'oblongatum' refers to this elongated body form. Females possess specialized scopal hairs on the underside of the for carrying pollen, characteristic of Megachilidae. Males may be distinguished by territorial and territorial markings, though specific diagnostic features require close morphological examination.

Images

Habitat

Warm, dry locations including flowering grasslands, hedges, and dry stone walls. Occupies sites such as weathering heaps, road embankments, railway embankments, and flood dams. Found in urban and suburban areas including flowering areas and rock gardens. Nesting sites are often spatially separated from pollen sources. Occurs from lowlands to montane elevations.

Distribution

Native to Eurasia from Portugal across southern, central and eastern Europe through Ukraine, southern Russia and Siberia (east to Tuva), and via Asia Minor, the Caucasus to the Central Asian mountains. European range extends north to the Netherlands, Brandenburg, central Poland and Belarus; south to Sicily, Thessaly, Iran and Afghanistan. Also native to Morocco. Introduced to North America, first detected in the eastern United States in 1995, now established throughout northeastern North America, Colorado, Utah, and the Pacific Northwest. First recorded in South America in central Chile in 2025.

Seasonality

period occurs in one from mid-June to early August.

Diet

Pollen and nectar. Shows strong floral specialization, collecting pollen almost exclusively from Fabaceae (especially Lotus and Onobrychis species, with Lotus corniculatus and Onobrychis viciifolia preferred), Crassulaceae (especially Sempervivum species and Sedum species, with Sedum reflexum preferred), and Resedaceae.

Host Associations

Lotus corniculatus - food plantpreferred pollen source
Onobrychis viciifolia - food plantpreferred pollen source
Sedum reflexum - food plantpreferred pollen source
Stelis punctulatissima - cuckoo bee , documented in France
Chrysis marginata - cuckoo wasp , likely based on observations from Germany and Switzerland

Life Cycle

, with one per year. Nests in pre-existing cavities, preferring horizontal crevices 5–6 mm wide in dry stone walls and weathered slate rocks. are constructed from plant fibers (vegetable wool) collected from leaves. The outside of the nest is marked with rust-colored glandular secretions.

Behavior

Females use their to scrape or 'card' plant fibers from hairy leaves to construct nest . Males are territorial and patrol territories around flowering plants. Nesting sites are often spatially separated from foraging areas for pollen and building materials.

Ecological Role

specialized on Fabaceae, Crassulaceae, and Resedaceae. Serves as for cleptoparasitic bees (Stelis punctulatissima) and parasitic (Chrysis marginata).

Human Relevance

Has been introduced to North America and South America, with potential ecological impacts through competition with native bees and disruption of local pollination networks. Populates gardens where suitable food plants and nesting materials are available.

Similar Taxa

Anthidium manicatumBoth are woolcarder bees in the same with similar nesting using plant fibers; A. oblongatum is more slender/oblong in body shape and has different floral associations
Anthidium florentinumOverlapping distribution and similar preferences in Europe; requires morphological examination for reliable separation

More Details

Nesting biology

Unlike some cavity-nesting bees that excavate their own burrows, A. oblongatum is an obligate cavity nester that relies on pre-existing spaces. The has been observed using passage-like cavities in buildings, similar to Anthidium manicatum.

Recent range expansion

The 2025 record from Chile represents a significant range expansion into South America, documented through citizen science platforms and field-collected specimens. This follows earlier introductions to North America.