SHARP-EATMAN
NATURE
PHOTOGRAPHY
ID GUIDE TO WILD BEES
OF THE NATIONAL BUTTERFLY CENTER
Mission, Texas
NOMAD CUCKOO BEES
Nomada
NOMAD CUCKOO BEES
Genus Nomada
Tribe Nomadini
Like the Epeolus and Triepeolus cuckoo bees shown on the previous page of this guide, Nomad bees are cleptoparasites belonging to the bee subfamily Nomadinae.
Nomad bees lay eggs in the nests of ground-nesting bees -- most commonly, Andrena mining bees. When the nomad eggs hatch in Andrena nests, the nomad larvae – which have large, sickle-like mouth parts -- kill off the Andrena larvae and eat the provisions left for them by the Andrena mother.
Some Nomada are generalists that parasitize the nests of multiple Andrena species. Others target specific host species. For example, the neighborly nomad bee (Nomada vicina) targets the nests of hairy-banded mining bees (Andrena hirticincta). The spotted nomad bee (Nomada maculata) preys on the neighborly mining bee (Andrena vicina). The beautiful nomad bee (Nomada bella) is a cleptoparasite of Andrena imitatrix.
Nomad bees also exist that prey on bees of other genera, including Agapostemon, Halictus, Lasioglossum, Colletes, Eucera, Exomalopsis, and Melitta. The most common nomad species found in the Lower Rio Grande Valley, Nomada texana, is thought to parasitize the nests of green Agapostemon sweat bees. The smaller Nomada vierecki is believed to parasitize the small bees of the genus Exomalopsis.
Species Identification Information:
Nomad bees are found throughout the world. There are nearly 300 nomad species in North America alone. Texas has a large array of Nomada. These include the Texas nomad bee and Vierecki's nomad bee, shown below, as well as the Nomada vegana shown at top right.
Nomad bees look wasp-like and tend to have the flashy appearance of custom-detailed race cars. They have sleek bodies, often adorned with well-defined stripes and crisp markings. They are usually red, black, yellow or a combination of these colors. Most nomad bees found in Texas have black or red bodies adorned with yellow markings; red or yellow legs; red, reddish-brown or partly yellow antennae; and red, green or brownish eyes.
General coloration varies from one type of nomad bee to another and can be used to help identify species. The Texas nomad bee, for example, can be identified in part by its black body, red legs, the yellow stripes on its abdomen, the yellow spots on its thorax, and its yellow facial mask.
Nomad bees have several distinctive minute traits that aid in identifying their genus: (1) the thoraxes of nomad bees are heavily pitted; (2) female nomad bees have specialized hair patches on the tips of their abdomens; (3) the pygidial plate (abdomen tip) of male nomad bees is pronounced and often notched; and (4) the jugal lobe of the nomad bee's wing is small. These traits are illustrated in the accompanying photo strip.
Pollinator Plants
Cuckoo bees do not gather pollen from flowers, because they obtain it instead by plundering other bees' nests. As a result, female nomad bees do not have scopae (pollen-collecting hairs) on their legs or abdomens. Nomad bees do, however, drink nectar from flowers. They tend to alight on flowers visited by their hosts or to patrol the ground looking for host bee nests.
A male Nomada vegana
Nomad bees have a wasplike appearance. They are slender, relatively hairless bees with bold markings.
The thoraxes of nomad bees are heavily pitted.
The jugal lobe (blue arrow) of the hind wing of the nomad bee is relatively small.
Characteristics of nomad bees
TAXONOMY OF NOMAD BEES
Order: Hymenoptera
Family: Apidae
Subfamily: Nomadinae
Tribe: Nomadini
Genus: Nomada
Species shown here:
Nomada texana (Texas nomad bee)
Nomada vierecki (Viereck's nomad bee)
Nomada Species of the National Butterfly Center
Texas nomad bee
Nomada texana (female)
Family: Apidae
Size: 11 mm (female)
9 mm (male)
Associated plants at NBC:
Seaside goldenrod
Solidago sempervirens
Romerillo
Bidens alba
(Family Asteraceae)
When found:
October 2019
A female Texas nomad bee (Nomada texana)
A female Texas nomad bee
Dorsal view of bee
The female bee's head and thorax are predominantly black, with yellow markings. Its legs are red. The female bee has two pale-yellow marks on its face. (On male Texas nomad bees, a yellow mask extends over a much larger portion of the face).
A male Texas nomad bee
The male Texas nomad bee has a yellow mask on its face. Male nomad bees often have more extensive facial markings than their female counterparts.
Dorsal view of male bee: like the female Nomada texana, the male has an abdomen banded by 5 yellow stripes and two distinctive yellow marks on the rear thorax, underscored by a yellow bar.
According to Texas bee expert John L. Neff, the Texas nomad bee, Nomada texana, is a common and widespread Texas species, but little is known about its habits. Possibly, it parasitizes the nests of green Agapostemon sweat bees.
At the National Butterfly Center, Texas nomad bees are most visible in late fall, when they emerge to nectar on goldenrod. During this same period, the honey-tailed Agapostemon sweat bee (Agapostemon melliventris) appears in large numbers at the NBC.
Nomada texana can be identified in part by its black body, red legs, reddish antennae and the yellow stripes on its abdomen and thorax. Among the most distinctive features of the bee are the two prominent yellow spots on the propodeum (the rear face of the thorax). The specific traits of this bee are noted in more detail in the accompanying photo strips.
The female bee shown here has two yellow marks on its face; the male Texas Nomad bee has a more extensive yellow mask covering most of its face. Such sexual dimorphism is common in nomad species.
A male Texas nomad bee
Viereck's nomad bee
Nomada vierecki (male)
Family: Apidae
Size: 7 - 8 mm (female and male)
Associated plants:
Found prowling under cenizo
(Leucophyllum frutescens)
(Family Scrophulariaceae)
When and where found:
May 29, 2021
Falcon State Park
Roma (Starr Co.)
A male Viereck's nomad bee (Nomada vierecki)
A male Nomada vierecki
A male Nomada vierecki: on male bees, T1-T6 are banded with uninterrupted pale-yellow stripes. On females of this species, T1-T5 are banded. T1 is often partly red on both males and females.
Dorsal view of male bee's thorax
Profile of face and thorax
Viereck’s nomad bee is relatively uncommon in the Lower Rio Grande Valley. The distribution of Nomada vierecki is centered along the western half of the Mexico-United States border, in New Mexico, Texas and Chihuahua.
Nomada vierecki is a relatively small, black, yellow and red nomad bee. The extensive reddish coloring on the bee's body helps distinguish it from other Valley species: red usually appears (on males) on parts of the bee's head; its antennae; its legs; T1 of its abdomen; its propodeum; and part of the sternum. The sternum of both the male and female Nomada vierecki is also banded with distinctive curved pale-yellow lines on S3 and S4.
Like the Texas nomad bee, Viereck’s nomad bee belongs to the vegana species group of the genus Nomada, whose members frequently prey on bee species other than Andrena. The smaller Viereck’s nomad bee is situated within the subgroup Micronomada, whose members are thought to parasitize the nests of small bees such as Exomalopsis and Halictidae. The male bee shown here was found on a cenizo bush mobbed by Exomalopsis birkmannni.
CITE THIS PAGE: Sharp, Paula and Ross Eatman. "Nomada." Wild Bees of the National Butterfly Center of Mission, Texas. 15 Jan. 2019, http://www.wildbeestexas.com. Accessed [day/month/year guide accessed].