SHARP-EATMAN
NATURE
PHOTOGRAPHY
ID GUIDE TO WILD BEES
OF THE NATIONAL BUTTERFLY CENTER
Mission, Texas
FAIRY BEES
Perdita
FAIRY BEES
Genus Perdita
Commonly known as fairy or miner bees, Perdita are small to very small bees that tend to be black, or metallic blue or brassy green, often with pale markings on their faces, bodies and legs. In some Perdita species, the pale markings are so expanded that the entire bee appears pale green or yellow. Some Perdita have dark reddish-orange abdomens or reddish markings. Most Perdita of the Valley are ant-sized.
Like the Protandrena and Calliopsis of this guide's preceding sections, Perdita belong to the subfamily Panurginae and are solitary bees that nest in the ground. Perdita sometimes nest near one another in aggregations; some live cooperatively, with several females sharing a common burrow or tunnel entrance. Although Perdita may waterproof provisions stored in egg chambers, they ordinarily do not line their nests with water-proofing materials, a trait unusual for ground-nesting bees.
Physical traits of Perdita
Perdita abdomens appear flattened when viewed from the side; this trait proves helpful in identifying the genus in the field. Close examination of the bees’ wings is also useful: as shown in the accompanying photo strip, the forewings of Perdita typically have two submarginal cells, and a marginal cell that is relatively short, lopped off at the end and bent away at nearly a right angle from the wing edge.
The genus Perdita harbors more than 650 known species, with many yet uncatalogued. Perdita species identification can prove tricky because of the bees' size and because species are separated by subtle traits far beyond the reach of the naked eye. The time of year in which Perdita emerge, and the flora on which they appear, aid in guessing species’ identities in the field, but strong magnification and expert assistance are usually required to pinpoint species.
A sampling of Lower Rio Grande Valley Perdita species representing three subgenera is shown in this guide section. Perdita (Cockerellia) tend to run larger than Perdita of other subgenera and to have yellow or yellow-banded abdomens. All collect pollen from large-flowered aster-family plants. Perdita (Hexaperdita) are relatively small and tend to be oligolectic on small-flowered Asteraceae. Perdita (Perdita) contains the majority of species within the genus. Members of this subgenus vary widely in appearance and forage on a diverse range of flowers.
A male Perdita (Cockerellia)
Traits of Perdita
A Perdita on the head of a dime: Perdita are small to very small bees.
Viewed from the side, the abdomens of Perdita look flat.
Many Perdita are darkly-colored bees with ivory or yellow markings.
TAXONOMY OF PERDITA
Order: Hymenoptera
Family: Megachilidae
Subfamily: Panurginae
Tribe: Perditini
Genus: Perdita
Species shown on this page:
Perdita (Cockerellia) scopata
Perdita (Hexaperdita) ignota
Perdita (Perdita) missionis)
Perdita of the National Butterfly Center & Lower Rio Grande Valley
Mission Fairy Bee
Perdita (Perdita) missionis
Family: Andreidae
Size: 4-5 mm (female)
2.75 - 3.75 mm (male)
Associated flora:
Bristly nama
(Nama hispidum)
Wavyleaf nama
(Nama undulatum)
Plant family: Boraginaceae
When and where found:
April 2019 & March 2021
McAllen Nature Center
McAllen (Hidalgo Co.)
The male Mission fairy bee has a dark head and thorax and an abdomen adorned with elongated ivory spots arranged in pairs.
The male bee's abdomen usually has 6 to 8 ivory spots.
Dorsal view of male bee, showing the pale spots on its abdomen
Male Perdita missionis have bright yellow markings on the lower half of the face and green eyes
A male Mission fairy bee (Perdita missionis)
The Mission fairy bee has a dark head and thorax and an abdomen adorned with elongated ivory spots arranged in pairs. Males have bright yellow markings on the lower half of the face, green eyes and yellow mandibles with red-to-black tips. Females' faces are black with blue eyes, and their mandibles are mostly reddish, black at the tips and yellow at the base. Females’ abdomens have six spots; those of males have six to eight spots.
Entomologist P. H. Timberlake named Perdita missionis after the town of Mission, Texas, because the first specimen of the species he examined had been collected in that Hidalgo County town. In 1958, Timberlake described the range of Perdita missionis as extending as far west into Texas as Terrell County, as far north as Mason County, and as far south as San Luis Potosi, Mexico.
In some parts of Texas, populations of Perdita missionis overlap with those of the very similar and far more widespread six-spotted fairy bee (Perdita sexmaculata). The two species differ only in minute traits invisible to the naked eye. (They include the number of joints in small mouthparts known as maxillary palpi and characteristics of the bees’ genitalia). Differentiating between the two species usually requires examination by an expert. In the field, the Mission fairy bee sometimes can be sorted from the six-spotted Perdita by plant choice: Perdita missionis is more likely to be found feeding on nama than is Perdita sexmaculata.
Ignored Fairy Bee
Perdita (Hexaperdita) ignota
Family: Andreidae
Size: 4.5 mm (female)
3.5 mm (male)
Associated plant:
Lazydaisy
(Aphanostephus ramosissimus)
Plant family: Asteraceae
When and where found:
April 27, 2021
McAllen Nature Center
McAllen (Hidalgo Co.)
This is a female Perdita ignota measuring barely four mm. The bee's head and body are dark and covered with fine white hairs. Its legs are dark brown, with brown basitarsi and yellowish-brown lower tarsi.
Dorsal view of a female bee on a lazydaisy: despite its small size, the ignored fairy bee's milky wings are a distinctive trait, visible even to the naked eye. This trait aids in identifying this species in the field.
The female ignored fairy bee has milky-blue facial markings: a large bell-shaped mark on the clypeus, flanked by two smaller spots.
Lateral view of bee: note the milky wings. The abdomens of females have faint hair bands as well as pale markings.
A female ignored fairy bee (Perdita ignota)
Perdita ignota is a minute, milky-winged, dark bee that glints gold in sunlight. The female bee has two pale broken bands on the second and third segments of its abdomen (T2-T3), and may have smaller pale dots on T4. The abdomen of the male bee is almost entirely dark except for the last segment, which is yellowish. Females' legs are dark and covered with fine pale hairs. Males' lower legs are ivory.
The ignored fairy bee is found throughout the central United States, from Montana to Mexico. It is common in Texas. It appears in the Lower Rio Grande Valley from April through November. Perdita ignota is a specialist pollinator of plants of the aster family and most likely to be found in the Valley on small-flowered Asteraceae.
Scopate Fairy Bee
Perdita (Cockerellia) scopata
Family: Andreidae
Size: 7-9 mm (female)
6-8 mm (male)
Associated flora:
Common sunflower
Helianthus annuus
Cowpen Daisy
Verbesina encelioides
Mexican hat
Ratibida columnifera
Plant family: Asteraceae
When and where found:
February - June 2021
El Mesteno Ranch
Puerto Rico (Hidalgo Co.)
A female Perdita scopata on cowpen daisy: this is a relatively large Perdita, measuring 9 mm, more than twice the size of other Perdita shown on this guide page.
The female Perdita scopata has a bronze head and thorax and an abdomen boldly striped with yellow bands.
The female has additional yellow markings on the pronotal collar and on the front of each pronotal lobe.
Lateral view of female bee: note the flat abdomen, a general trait of the genus Perdita. The black legs of the female Perdita scopata are covered with fine, pale hairs.
A female scopate fairy bee (Perdita scopata)
The beautiful female Perdita scopata has a shimmery bronze head and thorax and a dark abdomen striped with electric-yellow bands. Its eyes are a vibrant green. The male bee (not shown here) has a black abdomen faintly banded with pale hairs and usually lacking yellow markings. Both males and females have bright rust-orange mandibles that are yellowish at the base and dark at the tip. The bees’ wings are a glassy or translucent-white with pale yellow-orange veins, and their tegulae are reddish-brown. Females have dark legs; the tarsi and basitarsi of males are pale yellow.
Perdita scopata is found in coastal regions of Texas from Galveston to Brownsville. This species is common on large-flowered Asteraceae in all three border counties of the Lower Rio Grande Valley.
In the Valley, Perdita (Cockerellia) are represented by a continuum of similar species that sometimes cohabit the same area and intermingle on the same flowers. The female scopate fairy bee can be distinguished from others of its subgenus by the following features. (1) The female’s clypeus is usually dark with a median yellow vertical strip. (2) Its mandibles are hooked, at a near right angle to each base. (3) The yellow bands on the female bee’s abdomen (T2-T5) are broad, uninterrupted and of even width from side to side; they stop just short of reaching the abdomen’s lateral edges.
The facial characteristics of male Perdita scopata are variable and its facial markings frequently less prominent than on their female counterparts. On males of the subgenus Perdita (Cockerellia), the mandibles are long, tapering and curved rather than sharply angled.
CITE THIS PAGE: Sharp, Paula and Ross Eatman. "Perdita." Wild Bees of the National Butterfly Center of Mission, Texas. 15 Jan. 2019, http://www.wildbeestexas.com. Accessed [day/month/year guide accessed].