Eucera

Scopoli, 1770

long-horned bees

Species Guides

9

Eucera is a of solitary bees in the Apidae comprising more than 100 , commonly known as long-horned bees. Males are distinguished by exceptionally long , a trait reflected in the . These ground-nesting bees are found primarily in the Palearctic and Nearctic regions, where they serve as important of diverse flowering plants.

Eucera frater by (c) Don Loarie, some rights reserved (CC BY), uploaded by Don Loarie. Used under a CC-BY license.Eucera frater by (c) Don Loarie, some rights reserved (CC BY), uploaded by Don Loarie. Used under a CC-BY license.Eucera rosae, F, Face, MD, St Mary's County 2014-02-11-17.34.43 ZS PMax (12756650693) by USGS Bee Inventory and Monitoring Lab from Beltsville, Maryland, USA. Used under a Public domain license.

Pronunciation

How to pronounce Eucera: /juːˈsɛrə/

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

Identification

Males possess conspicuously long , often exceeding body length, which distinguishes them from females and most other . Old World Eucera can be identified by five or six maxillary palpomeres, a first flagellomere shorter than the scape, and a protruding beyond the by at least the 's width in lateral view. Males additionally show convergent carinae on the sixth abdominal segment. Body size ranges from 11–18 mm, with a thick layer of fur and dark coloration.

Images

Habitat

Ground-nesting in well-drained, sandy or loamy soils; found in meadows, fields, woodland rides and clearings, brownfield sites, coastal meadows, soft cliff , and urban gardens. Nests occur in , with tunnels extending up to 85 cm deep.

Distribution

Holarctic distribution spanning the Palearctic and Nearctic regions. Present in Europe, Asia, North Africa, and North America. Specific records include the Eastern Mediterranean, Bulgaria, Iran, Turkey, Cyprus, Syria, Israel, Greece, Lebanon, Egypt, and the United Kingdom (restricted to southern coasts).

Seasonality

Active primarily from spring through fall, with specific timing varying by region and . In the Middle East, activity occurs February through May. Eucera nigrilabris in Egypt flies from late January through late March. periods typically coincide with blooming of preferred plants.

Diet

forage for nectar and pollen. Some are visiting diverse flowers; others show specialization. Eucera cinerea possesses specialized thick, curved bristles for extracting pollen from flowers with hidden anthers. Eucera from southwest France primarily forage on Fabaceae and Brassicaceae. Subgenera Peponapis and Xenoglossa specialize on squash plants (Cucurbita pepo).

Life Cycle

Solitary bees with . Females construct and provision individual nests without social colonies. Nests contain vertical, elongated branching from main tunnels; Eucera nigrilabris nests contain two to three cells typically, with four to six cells in some cases. First cells in a series are often non-reproductive 'false cells'. Protandrous males typically emerge several days before females.

Behavior

Solitary nesting with females excavating and provisioning their own nests. Males patrol nest seeking mates, with aggressive competition observed in Eucera palaestinae and Eucera nigrilabris. Mating duration of 3–6 minutes has been recorded; females become unreceptive after mating. Foraging behavior includes avoidance of depleted food sources through reward-based patch-leaving rules and scent marking. Eucera palaestinae uses secretions to mark nests for homing in dense aggregations. Does not produce or respond to .

Ecological Role

Important of wild and agricultural plants. Contribute to pollination of legumes, sunflowers, and cucurbits. Serve as for cleptoparasitic bees including Nomada and Ammobates (Euphileremus) oraniensis.

Human Relevance

Eucera pruinosa (formerly Peponapis pruinosa) is an efficient of pumpkins, cucumbers, squash, and other cucurbits. Some have declined due to loss; Eucera longicornis has experienced dramatic range reduction in the UK. Conservation efforts focus on maintaining flower-rich grassland and coastal habitat.

Similar Taxa

  • AnthophoraFemale Eucera lack oversized and can be confused with Anthophora (flower bees); distinguished by Eucera's more robust build and, in males, the extremely long antennae absent in Anthophora.
  • BombusBoth are fuzzy, robust bees, but Eucera are solitary ground-nesters with different nesting and, in males, dramatically longer .
  • NomadaNomada are of Eucera nests; Nomada lack pollen-carrying structures and have -like appearance, while Eucera females carry pollen and have more robust, hairy bodies.

Sources and further reading