Anthidium porterae

Taxonomy

Family: Megachilidae
Subfamily: Megachilinae
Tribe: Anthidiini
Genus: Anthidium Fabricius, 1804
Subgenus: A. (Anthidium) Fabricius, 1804
Species: Anthidium porterae Cockerell, 1900
Common name: none

Overview

Anthidium (Anthidium) porterae are black, with some light ferruginous coloration on the legs and abdomen, and yellow maculations (Gonzalez and Griswold 2013). Females have white pubescence except for yellow pubescence on the vertex, scutum, axilla, scutellum, inner tarsi, and sometimes S6. The clypeus and distal half of the supraclypeal area are covered in apically hooked hairs. Females have a body length of 9.2–12.3 mm, and males vary in length from 11.5–13.1 mm (Gonzalez and Griswold 2013).

Diagnostic characteristics

(modified from Gonzalez and Griswold 2013)

May be confused with

Anthidium porterae can be differentiated from all Anthidium in the New World by the presence of the depressed apical rim that projects into a distinct ventral lateral lobe on female T6, and median preapical carina that projects as a long spine on male S6 (Gonzalez and Griswold 2013). Anthidium porterae may be confused with A. cochimi due to the clypeus with apically hooked hairs, tomentum on the outer hind basitarsi, and depressed apical rim that projects into a small ventral lobe on T6 (Gonzalez and Griswold 2013). Female A. porterae can be differentiated from A. cochimi by the presence of large, distinct preapical projections on the labrum and the elevated midline of T6 (Gonzalez and Griswold 2013).

Phenology

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

Host associations

Anthidium porterae is a generalist that has been observed visiting a variety of species within Apocynaceae, Asteraceae, Boraginaceae, Fabaceae, Loasaceae, and Plantaginaceae (Gonzalez and Griswold 2013).

Nesting behavior

Anthidium porterae has been observed nesting in shallow abandoned burrows in the ground (Custer and Hicks 1927). The nest contains a single cell that is comprised of plant trichomes from Artemisia campestris (Asteraceae) and Cryptantha sp. (Boraginaceae) (Custer and Hicks 1927). Nest plugs are constructed with pebbles. Males defend floral resources preferred by females (Villalobos and Shelly 1991).

Distribution

Anthidium porterae occur in the U.S. in Arizona, South Dakota, Nebraska, Oklahoma, Texas, Utah, and Wyoming. In Mexico, they are found in Baja California Sur, San Luis Potosi, and Chihuahuan to Aguascalientes. They are restricted to grasslands, Edwards Plateau savanna, Colorado Rockies, Arizona mountain forests, Colorado Plateau shrublands, Chihuahuan desert, Sierra Madre Occidental pine-oak forests, and central Matorral ecosystems (Gonzalez and Griswold 2013).


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

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