Anthidium clypeodentatum

Taxonomy

Family: Megachilidae
Subfamily: Megachilinae
Tribe: Anthidiini
Genus: Anthidium Fabricius, 1804
Subgenus: A. (Anthidium) Fabricius, 1804
Species: Anthidium clypeodentatum Swenk, 1914
Common name: none

Overview

Anthidium (Anthidium) clypeodentatum are black with yellow or cream-colored maculations and some dark brown coloration on their antennae, legs, and sterna. This species has two color morphs based on its location. Northern species have cream-colored markings, which are absent on the female’s face, mandible, and T6 (Gonzalez and Griswold 2013). Species on the Nevada-California border have yellow markings, which are present on the female’s face, clypeus, T1T6, and sometimes the mandible (Gonzalez and Griswold 2013). Females have white or yellow pubescence, which is darker on the fore and mid basitarsi, the inner hind basitarsi, and occasionally on S6. Females range in body length from 8.3–11.1 mm (Gonzalez and Griswold 2013). Males have yellow or brown pubescence on the vertex, scutum, and scutellum, and white hairs on the basitarsi. Males range in body length from 8.5–13.8 mm (Gonzalez and Griswold 2013).

Diagnostic characteristics

(modified from Gonzalez and Griswold 2013)

  • Tergal discs have sparse punctures that are 1–2 puncture widths apart.
  • Tergal disc depressed marginal areas have dense punctures that are about 1 puncture width apart.
  • Female antennal scape has a posterior surface covered in short, white tomentum.
  • Female clypeal distal margin is strongly toothed or tuberculate.
  • Female labrum has large, pre-apical projections, and lacks a basal protuberance.
  • Female mandible is seven-toothed.
  • Female propodeal triangle is shiny.
  • Female T1T5 has elevated discal areas and is slightly shiny between punctures.
  • Female T6 has a narrow projection on the mid-apical margin, and lacks a lateral projection.
  • Male labrum has low basal protuberances.
  • Male S4 has thick, reddish-brown hairs.
  • Male S6 basal margin is medially projected.
  • Male S6 median lobe is small and triangular.
  • Male S7 is slightly rounded.
  • Male S8 distal margin is projected medially, and is truncate and sclerotized.

May be confused with

Anthidium clypeodentatum may be confused with A. psoraleae due to the presence of short, white tomentum on the antennal scape, the medial projection on T6 in females, and a broad, lateral lobe on T7 with a sharp, angled inner margin in males (Gonzalez and Griswold 2013). Female A. clypeodentatum can be differentiated from A. psoraleae by the presence of a strongly toothed or tuberculate distal margin of the clypeus, and the lack of a lateral spine on T6 (Gonzalez and Griswold 2013). Male A. clypeodentatum can be differentiated from A. psoraleae by the presence of a small and triangular median lobe on S6 (Gonzalez and Griswold 2013).

Phenology

Anthidium clypeodentatum adults have been recorded in flight from April to August, with peak activity occurring from June to the first half of August (Gonzalez and Griswold 2013).

Host associations

Anthidium clypeodentatum is a generalist that favors Lotus and Astragalus (Fabaceae). However, they have been observed visiting a variety of species within Asteraceae, Fabaceae, and Rosaceae (Gonzalez and Griswold 2013).

Nesting behavior

Nesting behavior is unknown.

Distribution

Anthidium clypeodentatum is one of the most widely distributed Nearctic species. It occurs throughout western Canada in Yukon, British Columbia, Alberta, and Saskatchewan (Gonzalez and Griswold 2013). Within the U.S., A. clypeodentatum is found in Montana, North Dakota, South Dakota, and Colorado, and from California and Arizona to Washington. Within Mexico, it is distributed throughout northern Baja California. They are primarily found in chaparral, margins of the desert, and upper elevations of shrub steppe, montane forests, and grasslands (Gonzalez and Griswold 2013).


​Distribution map generated by Discover Life -- click on map for details, credits, and terms of use.

<p><em>Anthidium clypeodentatum</em> female face, photo: Tevan Brady</p>
Anthidium clypeodentatum female face, photo: Tevan Brady
<p><em>Anthidium clypeodentatum</em> female lateral habitus, photo: Tevan Brady</p>
Anthidium clypeodentatum female lateral habitus, photo: Tevan Brady
<p><em>Anthidium clypeodentatum</em> female abdomen, photo: Tevan Brady</p>
Anthidium clypeodentatum female abdomen, photo: Tevan Brady
<p><em>Anthidium clypeodentatum</em> female, diagram showing the dorsal view of the sixth tergite (T6), diagram from Gonzalez and Griswold 2013</p>
Anthidium clypeodentatum female, diagram showing the dorsal view of the sixth tergite (T6), diagram from Gonzalez and Griswold 2013
<p><em>Anthidium clypeodentatum</em> male face, photo: Tevan Brady</p>
Anthidium clypeodentatum male face, photo: Tevan Brady
<p><em>Anthidium clypeodentatum</em> male lateral habitus, photo: Tevan Brady</p>
Anthidium clypeodentatum male lateral habitus, photo: Tevan Brady
<p><em>Anthidium clypeodentatum</em> male abdomen, photo: Tevan Brady</p>
Anthidium clypeodentatum male abdomen, photo: Tevan Brady
<p><em>Anthidium clypeodentatum</em> male, ventral view of fourth sternum (S4), photo from Gonzalez and Griswold 2013</p>
Anthidium clypeodentatum male, ventral view of fourth sternum (S4), photo from Gonzalez and Griswold 2013
<p><em>Anthidium clypeodentatum</em> male, dorsal view of seventh tergum (T7), photo: Tevan Brady</p>
Anthidium clypeodentatum male, dorsal view of seventh tergum (T7), photo: Tevan Brady
<p><em>Anthidium clypeodentatum</em> male, diagram showing dorsal view of seventh tergum (T7), diagram from Gonzalez and Griswold 2013</p>
Anthidium clypeodentatum male, diagram showing dorsal view of seventh tergum (T7), diagram from Gonzalez and Griswold 2013
<p><em>Anthidium clypeodentatum</em> male, diagram showing ventral view of sixth sternum (S6), diagram from Gonzalez and Griswold 2013</p>
Anthidium clypeodentatum male, diagram showing ventral view of sixth sternum (S6), diagram from Gonzalez and Griswold 2013
<p><em>Anthidium clypeodentatum</em> male, diagram showing ventral view of seventh sternum (S7), diagram from Gonzalez and Griswold 2013</p>
Anthidium clypeodentatum male, diagram showing ventral view of seventh sternum (S7), diagram from Gonzalez and Griswold 2013
<p><em>Anthidium clypeodentatum</em> male, diagram showing ventral view of eighth sternum (S8), diagram from Gonzalez and Griswold 2013</p>
Anthidium clypeodentatum male, diagram showing ventral view of eighth sternum (S8), diagram from Gonzalez and Griswold 2013