SHARP-EATMAN
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ID GUIDE TO FLORIDA BEES
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Mission, Texas
ROTUND RESIN BEES
Anthidiellum perplexum
ROTUND RESIN BEES
Tribe Anthidiini - Genus Anthidiellum
Anthidiellum of the United States are small, robust bees with relatively hairless, coarsely-pitted bodies. They are usually black with brightly-colored yellow or red markings.
Female Anthidiellum of North America construct their nests above ground and in the open. Their nests are made of resin and consist of single isolated cells, or groups of cells, which the bees attach to stems, leaves and rocks.
Distinguishing traits of the genus Anthidiellum
Traits that aid in distinguishing bees of the genus Anthidiellum are shown in the accompanying photo strip. Most notably, an Anthidiellum can be identified by any of these traits: (1) The sutures (seams) under the bee's antennae curve strongly outward; (2) the bee's scutellum (second thorax segment) extends backward like a shelf, overhanging the body behind it; (3) the mesipisternum (the side of the thorax) is divided into a pitted front face and a coarsely-sculptured back face.
Like other members of the family Megachilidae shown in this guide, Anthidiellum have forewings with two submarginal cells, and their tarsi (feet) have arolia.
A male Anthidiellum perplexum
FROM TEXAS SITE: TRAITS OF ANTHIDIELLUM - ROTUND-RESIN BEES
Anthidiellum are robust bees that are usually black with yellow or red markings. Their legs may be black or red, sometimes with yellow markings.
The sutures (seams) under the antennae of Anthidiellum are curved.
Rather than forming a rounded curve, the back of the bee's head has a sharp edge that descends in a vertical face. On Anthidiellum of North America, the back of the head is usually rimmed with with a broad yellow (or red) band.
Anthidiellum species and subspecies
Early texts on North American Anthidiellum species separated them largely by geography and color -- although within a given species, individual specimens often show significant color variation. Other traits used to distinguish Anthidiellum species include the shape of the clypeus (the face-part above the mandibles); characteristics of the tip of the abdomen; traits of the bees' genitalia; and the length of the hairs on males' forelegs.
Anthidiellum occur throughout the world; they are represented by more than 60 species divided into 7 subgenera. In North America, however, there are only a handful of Anthidiellum species, all belonging to the genus Loyolanthidium. The three most common North American species are Anthidiellum notatum, A. perplexum, and A. ehrhorni. Only the first of these appears in Texas.
The species Anthidiellum notatum is currently divided into 5 subspecies. During different periods of taxonomic history, some of these subspecies have acquired species status, and arguably most of them should. The differences among these subspecies are set forth in the second guide entry below.
The last reliable records of Anthidiellum anywhere in the Lower Rio Grande Valley are more than 70 years old: they consist of reports from 1940 and 1951 noting finds of the subspecies Anthidiellum notatum boreale in Cameron County.
TAXONOMY OF ANTHIDIELLUM (ROTUND-RESIN BEES)
Order: Hymenoptera
Family: Megachilidae
Subfamily: Megachilinae
Tribe: Anthidiini
Genus: Anthidiellum
Species shown on this page:
Anthidiellum (Loyolanthidium) perplexum
Anthidiellum Species of Florida
The ID for the male bee was confirmed at bugguide: https://bugguide.net/node/view/1707678/bgimage and here at I-Nat
https://www.inaturalist.org/observations/61733853
The ID for the femlae bee was confirmed here at bug guide: https://bugguide.net/node/view/1712980/bgimage
Perplexing rotund-resin bee
Anthidieullum perplexum
Family: Apidae
Size: 8 mm (female), 9 mm (male)
Associated plants:
Milkpea
(Galactia)
Plant family: Fabiaceae
When and where seen:
August 6, 2019 (male )
August 10, 2019 (female)
St. Augustine, FLA
(St. Johns County)
A male Anthidiellum perplexum
Dorsal view of a male perplexing rotund resin bee
Lateral view of male bee
A female perplexing rotund resin bee
Dorsal view of female bee
A female Anthidiellum perplexum
CITE THIS PAGE: Sharp, Paula and Ross Eatman. "Anthidiellum." Wild Bees of the National Butterfly Center of Mission, Texas. 15 Jan. 2019, http://www.wildbeestexas.com. Accessed [day/month/year guide accessed].