Anthidium pallidiclypeum

Taxonomy

Family: Megachilidae
Subfamily: Megachilinae
Tribe: Anthidiini
Genus: Anthidium Fabricius, 1804
Subgenus: A. (Anthidium) Fabricius, 1804
Species: Anthidium pallidiclypeum Jaycox, 1963
Common name: none

Overview

Anthidium (Anthidium) pallidiclypeum are dark brown to black with reddish-brown tarsi, light brown apical rims of terga, and yellow maculations (Gonzalez and Griswold 2013). Females have white to light ferruginous pubescence that is slightly darker on the vertex, scutum, axilla, scutellum, inner tarsi, and S6. Females have a body length of 9.2–13.5 mm, and males range in length from 10.0–12.3 mm (Gonzalez and Griswold 2013).

Diagnostic characteristics

(modified from Gonzalez and Griswold 2013)

  • Female labrum is basally elevated with two large preapical projections that curve upwards.
  • Female mandible usually has 5–6 teeth.
  • Female propodeal triangle is weakly shiny and finely lineolate to imbricate.
  • Female hind tibia without anterior carina.
  • Female T1T5 discal areas are weakly elevated and dull and weakly shiny between punctures.
  • Female T1T5 depressed marginal zones have fine, dense punctures.
  • Female T1T5 impunctate apical zones are dull and narrow.
  • Female T6 lacks lateral spines.
  • Male S4 with median apical brush of reddish-brown, sparse hairs that can be difficult to see among the other hairs on the sternite.
  • Male S4 apical margin is straight medially.
  • Male S6 lacks lateral lobes, and the median lobe is broad and truncate or slightly rounded.
  • Male S7 is truncate apically.
  • Male S8 apical process is long, narrow, and apically bifid with ventrally bent lobes.
  • Male T6 lateral spine is straight and about as long as T7 median spine.
  • Male T7 lateral lobes rounded apically and 1.3–1.5 times wider than the distance between the inner margin and median spine.

May be confused with

Anthidium pallidiclypeum may be confused with A. edwardsii and A. placitum because of the distinctly concave apical margin of the clypeus. The clypeus of A. pallidiclypeum differs from these other species in that it lacks strong sub-lateral projections on the apical margin (Gonzalez and Griswold 2013). Male A. pallidiclypeum can be distinguished by the reddish-brown median apical brush on S4, the shape of the T7 lateral lobes, and the bifid apical process of S8 having clubbed ends (Gonzalez and Griswold 2013).

Phenology

Anthidium pallidiclypeum adults have been recorded in flight from late April to early July, with peak activity occurring from the last half of May to the first half of June (Gonzalez and Griswold 2013).

Host associations

Anthidium pallidiclypeum is a generalist that has been observed visiting a variety of species within Asteraceae, Boraginaceae, Cactaceae, Fabaceae, Lamiaceae, Plantaginaceae, Polygonaceae, Ranunculaceae, and Rhamnaceae (Gonzalez and Griswold 2013).

Nesting behavior

Nesting behavior is unknown.

Distribution

Anthidium pallidiclypeum occur in the U.S. in California and southern Nevada. They are restricted to mountainous areas of the Mojave Desert, California chaparral and woodlands, and southeastern Great Basin shrub steppe ecosystems. In Mexico, they are commonly found in Baja California (Gonzalez and Griswold 2013).


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

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