SHARP-EATMAN
NATURE
PHOTOGRAPHY
What is an Anthidium?
Anthidium, commonly known as woolcarder bees, belong to the same family as leafcutter bees – Megachilidae. Anthidium are robust, small to medium-sized, hairy bees, usually black with yellow or pale markings. Females have large mandibles equipped with numerous teeth.
Female Anthidium engage in distinctive behavior – they wield their many-toothed mandibles to scrape fibers from fuzzy plants, such as lamb’s ears, and use the fibers, mixed with plant resins, to construct their nests. The common name "woolcarder bee" derives from this practice -- theoretically, Anthidium behavior resembles that of a woolcarder combing raw sheep wool to untangle it.
Female Anthidium of various species have long hairs on the lower legs used to comb and pack fibers into balls when constructing nests. Females usually nest in the ground, sometimes filling parts of their nests with pebbles. In some species, females nest in holes and crevices found in wood or manmade structures.
Traits of the Genus Anthidium
Like leafcutters and other Megachilidae, Anthidium females carry pollen on hairs located on the underside of the abdomen, rather than on their hind legs like most bees. The wings of Anthidium have two submarginal cells, a trait of most Megachilidae; the stigma of an Anthidium wing is also small and narrow. These traits are shown in the accompanying photo strip.
Male Anthidium are typically larger than females, an unusual trait in the bee world generally. The feet (tarsi) of both male and female Anthidium lack arolia, pad-like structures between the claws that operate like suction cups and that allow many bees (such as honey and bumble bees) to walk on vertical surfaces.
Geographic range of Anthidium
Anthidium are found in all continents except Australia and Antarctica. Within the United States, there are more than thirty native species and subspecies. Most live in the West and Southwest.
Only two native species are found in the eastern United States – Anthidium maculifrons and A. psoraleae. Neither occurs in New York. The two species shown below on this page – the European woolcarder bee (Anthidium manicatum) and the oblong woolcarder bee (Anthidium oblongatum) are non-native species that have become well-established in the northeastern United States.
Two other adventive woolcarder bee species of two different genera have been documented in New York in the last decade via iNaturalist: a sighting of the Florentine woolcarder bee (Anthidium florentinum) was reported in Clinton County on Sept. 4, 2021; and a European small woolcarder bee (Pseudoanthidium nanum) was found in Buffalo, New York, on August 31, 2026.
A male Anthidium oblongatum (oblong woolcarder bee)
TRAITS OF ANTHIDIUM
This is an Anthidium.
Anthidium are black bees that usually have yellow or pale markings on their abdomens. The bands on their abdomens tend to be interrupted in the middle.
The faces of Anthidium also usually have pale markings. Such markings differ on males and females and are sometimes used to differentiate species. (Here, the male is above and the female below.)
European Woolcarder Bee
Anthidium manicatum
(Subgenus Anthidium)
Size: 9-12 mm (female)
12-18 mm (male)
European woolcarder bees build solitary nests in pre-existing cavities found in wood, manmade structures, or the ground. Females line their nests with fibers scraped from hairy garden plants such as lamb's ears, hedgenettle, mullein, rose campion and globe thistles.
Females provision their nests with pollen and nectar collected from a variety of flora. They are common visitors of such standard New York garden plants as butterfly bush, bugloss, cosmos, goldenrod, lavender, and yarrow. They are also useful pollinators of melons, squash, peas, beans and commercially grown flowers such as snapdragons.
In the northeastern United States, European woolcarder bees are often associated with mint-family plants. If you plant an herb garden in southern New York, replete with mints such as oregano, salvia, bergamot and calamint, and add a small patch of lamb's ears or mullein, European woolcarder bees are likely to arrive.
Males of this species are territorial and can be spied fighting off larger pollinators such as bumble bees and carpenter bees. Male woolcarder bees have a habit of hovering over flowers in midflight. They tend to patrol a small patch of garden or a single flowering plant, policing it for the presence of other bees. When an intruder insect enters a carder bee's territory to feed on a flower, the woolcarder bee will chase the intruder away, or ram it like a miniature rhinoceros to knock it off the flower.
Non-native status: As noted above, European woolcarder bees are not native to the United States. They originate from Europe, Asia, and North Africa, and arrived in New York in 1963. They have since spread through the United States and are now found as far south in the Americas as Brazil and Argentina. Anthidium manicatum are not currently considered a significant threat to native pollinators or honey bees, and they do not transmit agents that lead to colony collapse disorder. Nonetheless, they are considered an invasive species.
Identification information: Both male and female Anthidium manicatum are black bees with yellow markings on the face and body, and legs that are either partly yellow, or (on females) partly yellow and rust-orange. Males are much larger than females, and the two genders differ enough that they might be mistaken for different species.
FEMALES:
Distinguishing traits. The female Anthidium manicatum can be distinguished from A. obligatum by these combined traits.
(1) The scutellum (2nd thorax segment) of the female Anthidium manicatum has a smooth rim, without teeth on either side.
(2) The abdomen is black, with yellow bands on T1-T5 (first through fifth abdomen segments). The bands are broad and interrupted in the middle by black; the interruptions become narrower toward the rear, so that the central black area between the bands forms a V-shape.
(3) There are two black teeth on the outer edges of the bottom rim of the clypeus – between these are 3-5 yellow knobs. (A more detailed description of the face follows below.)
General description of female:
Head & face: Facial markings vary among individual female oblong woolcarder bees. Typically, the female's head is black, with yellow on the outer mandibles and the entire lower half of the clypeus, except for a small black area in the central portion. There is sometimes a yellow spot on the vertex. Yellowish to reddish hairs cover parts of the head and face.
The rim of female's clypeus is as described above. According to entomologists Gonzalez & Griswold (2013), females' mandibles have 6-8 teeth on each side. The antennae are entirely black.
Thorax: The female's thorax (scutum & scutellum) may be entirely black, or may have yellow markings along the borders of the scutum and on the rear of the scutellum, as shown on the bee in the accompanying photo strip. The tegulae (plates where the wings join the body) are usually partly yellow. The female's thorax is covered by long, pale hairs, especially dense along the sides (mesepisternum).
Legs: On females, the middle and hind femurs (3rd leg segments) are sometimes yellow and sometimes orangish-brown. The tibiae (4th segments) are usually partly yellow. Females have dense hairs on the outer basitarsi (lower legs).
Abdomen: As noted above, the female has distinctive yellow bands on T1-T5. T6 is usually bare, but sometimes has two yellow spots. The bee's scopal hairs, located on the sternum (under the abdomen) are white and pale reddish or pale yellow.
MALES:
Distinguishing traits: Males can be distinguished from other Anthidium by these traits: there are tufts of conspicuous curled hairs on T2-T5; and there are three curved spinelike prongs on T7.
General description:
Face: Much of the male's face is yellow, including the mandibles, nearly all of the clypeus (except the bottom rim), and the area between the clypeus and lower edges of the compound eyes. The antennae are entirely black.
Legs: The males’ tibiae and tarsi (lower legs) are yellow or partly yellow.
Thorax and abdomen: Males have less extensive yellow markings than females: the thorax is usually all black, and the abdomen lacks the bold stripes of the female's.
The yellow markings on the male's abdomen differ fairly widely among individual specimens. Onthe specimens shown here, T1-T2 have rectangular yellow markings on the sides of the segments; on T3-T4, there are series of irregular, somewhat rectangular markings that stretch across the sides and middle of the segments. T5-T6 have broad bands that are interrupted in the middle.
On other male specimens, the yellow markings may be more or less prominent on T3-T4 -- or may be missing altogether.
A female European woolcarder bee (Anthidium manicatum)
A male European woolcarder bee (Anthidium manicatum)
Female bee
A female European woolcarder bee (Anthidium manicatum)
Lateral view of female bee
Frontal view of bee
Male bee
A male European woolcarder bee on a leaf of selfheal. Note that there are broken bands on T4-T6, but T1-T3 are mostly black in the center.
Here is the woolcarder bee guarding its territory -- a clump of betony flowers.
The carder bee pursues a yellow jacket wasp through through the flowers.
QUICK IDENTIFICATION TRAITS
FEMALE: European woolcarder
FACE: The bottom rim of the clypeus (lower face) has two outer black teeth separated by yellow knobs.
FACE: The lower half of the face is mostly yellow.
FACE: Mandibles have 6-8 teeth on each side.
THORAX: The rear rim of the thorax (scutellum) is smoothly curved, without teeth.
ABDOMEN: Interrupted, broad yellow bands create a black V-shape along the length of the abdomen.
QUICK IDENTIFICATION TRAITS
MALE: European woolcarder
ABDOMEN: There are three curved prongs on T7 (the rearmost segment)
ABDOMEN: There are conspicuous tufts of curled hairs on T2-T5.
A male oblong woolcarder bee (Anthidium oglongatum)
Identification information:
Male and female Anthidium oblongatum are more alike than is true of male and female Anthidium manicatum. Oblong woolcarder males and females are closer in size, and they are similar in appearance. The two sexes can be distinguished most easily in the field by counting the yellow bands on the bees' abdomens: males typically have 6 bands, and two spots on the rearmost segment. (Females' markings vary; they consist of broken bands or spots & appear on 5 segments.)
Both male and female Anthidium oblongatum are black, hairy bees with yellow markings on the face and mandibles; on the tegulae (plates where the wings join the body); and on the abdomen. The legs of both male and female bees are partly yellow and often partly orange; orange markings are more extensive on the female. The wings of Anthidium oblongatum are transparent brown. Females have long, pale scopal hairs on the sternum (underside of the abdomen). Males' abdomens are also hairy underneath.
Both males and females have a distinctive trait, apparent under high magnification: the pronotal lobes and scutellum are lamellate -- that is, they are structured like a series of scales stacked on one another. (The pronotal lobes are roughly round plates situated on each side of the front of the thorax; the scutellum is the second thorax segment).
In addition, both males and females have extensive pale or yellow markings on the face and mandibles, and entirely black antennae. Both have two yellow markings on the rear vertex (top of the head). And both also tend to lack markings on the upper thorax (the scutum and scutellum).
As noted, the abdomens of males typically have 6 yellow bands on the first six segments (T1-T6), and two spots on T7. The bands are broad and interrupted.
On females, yellow markings appear on T1-T5 and vary among individual specimens. T1-T3 usually have widely interrupted bands. On T4-T5, the yellow areas are often reduced to irregular yellow spots arranged in rows across the width of the segment, as shown in the accompanying photo strip.
Other traits specific to males and females are noted below.
FEMALES:
Distinguishing traits: These traits of the face and thorax distinguish Anthidium oblongatum females from female A. manicatum:
Face:
(1) Face: The female's face typically has extensively black areas. Yellow facial markings on females vary among individuals, but usually cover the outer mandibles and part of the clypeus, and appear along the inner edges of the lower compound eyes.
(2) Face: The mandibles of female A. oblongatum have 9-12 teeth on each side. (Another detail: the tooth near the base is much larger than the tooth closest to the tip.)
(3) Thorax: The rear rim of the female's scutellum (2nd thorax segment) has two teeth on the outer edges. This trait distinguishes female Anthidium oblongatum from all other Anthidium of the United States.
MALE:
Distinguishing traits: Two traits of the abdomen, in combination, distinguish male Anthidium oblongatum from male A. manicatum..
Abdomen: (1) A spine projects from the rear of the sixth abdomen segment (T6). (2) T7 is divided into two lobes.
Mating male (top) and female (bottom oblong woolcarder bees
Female bee
A female oblong woolcarder bee
Male (top) and female (bottom) oblong woolcarder bees mating
Male (top) and female (bottom) oblong woolcarder bees mating: note the female's largely black face. Yellow facial markings on females vary among individuals, but usually cover the outer mandibles and part of the clypeus, and appear along the inner edges of the lower compound eyes.
Male bee
A male oblong woolcarder bee
Male (top) and female (bottom) oblong woolcarder bees mating. Note that the male's legs are more yellow than orange -- while the females' are largely orange.
Alternate view of male bee
QUICK IDENTIFICATION TRAITS
FEMALE: Oblong woolcarder
FACE: Mandibles have 9-12 teeth on each side.
FACE: The female's face has extensive black areas, even in the lower half. (The outer mandibles and parts of the lower face are yellow.)
THORAX: The rear rim of the thorax (scutellum) has teeth on either side of the back rim.
ABDOMEN: Yellow bands very widely interrupted or reduced to irregularly-shaped yellow spots. Yellow bands are narrower than those of female Anthidium manicatum.
QUICK IDENTIFICATION TRAITS
MALE: Oblong woolcarder
ABDOMEN: A spine projects from the rear of the T7 ( sixth abdomen segment.
ABDOMEN: T7 is divided into two lobes.
Oblong Woolcarder Bee
Anthidium oblongatum
(Subgenus Proanthidium)
Size: 8-10 mm (female)
8.5-13 mm (male)
Like the European woolcarder bee shown above, the oblong woolcarder bee is not native the United States; it arrived here from Europe in the nineties. The two bee species are somewhat similar in general form and general appearance, but the oblong woolcarder bee occupies a separate subgenus (Proanthidium), and has different physical traits and somewhat different behavior.
Like other Anthidium, female oblong woolcarder bees card fibers from hairy plants to use in nest construction. Anthidium oblongatum have been recorded collecting fibers from the following non-native plants that have become common in American gardens or weedy areas: downy hedgenettle (Stachys germanica), dusty miller (Jacobaea maritima), globe thistle (Echinops trio), lamb's ear (Stachys byzantina), mullein (Verbascum thapsus) and strawflower (Helichrysum sp.).
Oblong woolcarder bees tend to appear in New York gardens that contain at least one of the hairy plants enumerated above and stonecrop (Hylotelephium spectabile) -- a non-native and popular ornamental succulent with pink or white flowers often sold under the name "Sedum". Both male and female oblong woolcarder bees feed on stonecrop nectar, and females gather pollen from it.
Oblong woolcarder bees are also commonly found feeding on chicory (Cichorium intybus), pea-family plants such as vetch (Vicia), and garden mints such as calamint and mountain mint. The bees' flower of choice is birdsfoot trefoil (Lotus corniculatus), a common non-native weedy plant of the pea family.
RECOMMENDED REFERENCES
Ascher, John S. & John Pickering. 2022. Discover Life Bee Species Guide and World Checklist.
Burrows, S., C. Ritner, M. Christman, L.R. Spears, A. Smith-Pardo, S. Price, R.A. Ramirez, T. Griswold, & A.J. Redford. 2021. Exotic Bee ID. USDA APHIS Identification Technology Program (ITP) and Utah State University. Fort Collins, Colorado.
Gibbs, Jason & Cory S. Sheffield. 2009. Rapid range expansion of the wool-carder bee, Anthidium manicatum (Linnaeus) (Hymenoptera: Megachilidae), in North America. Journal of the Kansas Entomological Society 82: 21-29.
Gonzalez, Victor H. and Terry L. Griswold. 2013. Wool carder bees of the genus Anthidium in the Western Hemisphere (Hymenoptera: Megachilidae): diversity, host plant associations, phylogeny, and biogeography. Zoological Journal 168: 221–425.
Hoebeke, E. Richard & Alfred G. Wheeler, Jr. 1999. Anthidium oblongatum (Illiger): an old world bee (Hymenoptera: Megachilidae) new to North America, and new North America records for another adventive species, A. manicatum (L.). The University of Kansas Natural History Museum Special Publication 24: 21–24.
Kurtak, Barbara H. 1973. Aspects of the biology of the European bee Anthidium manicatum (Hymenoptera: Megachilidae) in New York State. MS Thesis. Cornell University.
Michener, Charles D. 2007. The Bees of the World (2nd ed.). Johns Hopkins University Press, Baltimore and London, 953 pp.
Michener, Charles D., & Terry L. Griswold. 1994. The classification of old world Anthidiini. University of Kansas Science Bulletin 55: 299-327.
Mitchell, Theodore B. 1962. Bees of the Eastern United States. Volume 2. North Carolina Agricultural Experimental Station Technical Bulletin No. 152.
Miller, Shane R., Robert Gaebel, Randall J. Mitchell, & Michael Arduser. 2002. Occurrence of two species of old world bees, Anthidium manicatum and A. oblongatum (Apoidea: Megachilidae), in Northern Ohio and Southern Michigan. The Michigan Entomology Society 35: 65–69.
Müller, Andres, W. Topfl, & Felix Amiet. 1996. Collection of extrafloral trichome secretions for nest wool impregnation in the solitary bee Anthidium manicatum. Naturwissenschaften 83: 230–232.
O’Brien, Mark F., Daniel R. Swanson, & Jeremy Monsma. 2012. Anthidium oblongatum (Apoidea: Megachilidae) confirmed as a Michigan resident, with notes on other Michigan Anthidium species. The Great Lakes Entomologist 45: 102–105.
Payne, Ansel, Dustin A. Schildroth, & Philip T. Starks. 2011. Nest site selection in the European wool carder bee, Anthidium manicatum, with methods for an emerging model species. Apidologie 42: 181–191.
Pechuman, Laverne L. 1967. Observations on the behavior of the bee Anthidium manicatum (L). Journal of the New York Entomological Society 75: 68–73.
Strange, James P., Jonathan B. Koch, Victor H. Gonzalez, Lindsay Nemelka, & Terry L. Griswold. 2011. Global invasion by Anthidium manicatum (Linnaeus) (Hymenoptera: Megachilidae): assessing potential distribution in North America and beyond. Biological Invasions 13: 2115.
Tonietto, Rebecca K., & John S. Ascher. 2009. Occurrence of the old world bee species Hylaeus hyalinatus, Anthidium manicatum, A. oblongatum, and Megachilidae sculpturalis, and the native species Coelioxys banksi, Lasioglossum michiganense, and L. zophops in Illinois (Hymenoptera: Apoidea: Colletidae, Halictidae, Megachilidae). The Great Lakes Entomologist 41: 200–203.
Wirtz, Peter, Michael Szabados, Horst Pethig, & John Plant. 1988. An extreme case of interspecific territoriality: male Anthidium manicatum (Hymenoptera: Megachilidae) wound and kill intruders. Ethology 78: 159–167.