Anthidium palliventre

Taxonomy

Family: Megachilidae
Subfamily: Megachilinae
Tribe: Anthidiini
Genus: Anthidium Fabricius, 1804
Subgenus: A. (Anthidium) Fabricius, 1804
Species: Anthidium palliventre Cresson, 1878
Common name: none

Overview

Anthidium (Anthidium) palliventre are dark brown to black with reddish-brown coloration on the tarsi and yellow maculations (Gonzalez and Griswold 2013). Females have white pubescence except for dark brown hairs on the inner tarsi and centers of S2S6, and ferruginous hairs on the vertex, pronotal lobe, scutum, axilla, and scutellum (Gonzalez and Griswold 2013). Females have a body length of 8.5–10.6 mm, and males vary in length from 10.0–15.4 mm (Gonzalez and Griswold 2013).

Diagnostic characteristics

(modified from Gonzalez and Griswold 2013)

  • Female labrum is elevated basally with two large preapical projections that curve upwards.
  • Female mandible has six teeth.
  • Female propodeal triangle is dull to weakly shiny and finely lineolate to imbricate.
  • Female hind tibia without anterior carina.
  • Female T1T5 discal areas are weakly elevated and dull or weakly shiny between punctures.
  • Female T1T5 depressed marginal zones have fine, small, dense punctures.
  • Female T1T5 impunctate apical zones are dull and narrow.
  • Female T6 has distinct lateral angles.
  • Male S4 with median apical brush of dense, small, and dark brown hairs.
  • Male S6 with acute, ventrally directed, lateral lobes, and a bidentate median lobe.
  • Male S7 is truncate apically.
  • Male S8 apical process is bifid with ventrally bent, pointed lobes.
  • Male T6 lateral spine is straight, and as long as the T7 median spine.
  • Male T7 lateral lobe tapers distally, is usually curved, and is 1.3 times wider than the distance between the inner margin and median spine.

May be confused with

Anthidium palliventre can be easily differentiated from all other Anthidium in the U.S. by the fringe of long hairs on the posterior margin of the fore basitarsus. Male A. palliventre can be distinguished by the combination of an apically curved lateral lobe on T7, acute lateral lobes and a bidentate median lobe on S6, and an apically bifid S8 (Gonzalez and Griswold 2013).

Phenology

Anthidium palliventre adults have been recorded in flight from April to late September; however, one specimen was recorded in late October. Peak activity occurs from May to July (Gonzalez and Griswold 2013).

Host associations

Anthidium palliventre is a generalist that has been observed visiting a variety of species within Asteraceae, Boraginaceae, Brassicaceae, Crassulaceae, Fabaceae, Nyctaginaceae, Polemoniaceae, Polygonaceae, and Rosaceae (Gonzalez and Griswold 2013).

Nesting behavior

Anthidium palliventre construct nests in the sand. They excavate their nests with aid from a fringe of long hairs on the posterior margin of the fore basitarsus (Hicks 1928). Males have been observed displaying territorial behaviors, such as guarding the host plants that are preferred by the females (Villalobos and Shelly 1991).

Distribution

Anthidium palliventre are native to the west coast of the United States, where they have been observed nesting in sand dunes. Although most frequently found from southern California to northern Oregon, Anthidium palliventre have been recorded as far north as Alaska (Armbruster and Guinn 1989; Gonzalez and Griswold 2013).


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

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