Anthidium (Anthidium) hallinani are primarily dark brown to black with yellow maculations and reddish-brown antennal flagellum, tegula, distal half of the femora, inner tibiae and tarsi, and sterna (Gonzalez and Griswold 2013). Females have white pubescence, except for brown to light ferruginous hairs on the vertex, pronotal lobe, dorsal area of the mesepisternum and metepisternum, propodeum, scutum, axilla, scutellum, inner tarsi, and S6. Females and males have a body length of 9.2–11.2 mm and 10.3–14.6 mm, respectively (Gonzalez and Griswold 2013).
(modified from Gonzalez and Griswold 2013)
Anthidium hallinani may be confused with A. aztecum based on the dull and finely and densely punctate terga with elevated discal areas, the shape of female T6, and male genitalia and sterna (Gonzalez and Griswold 2013). Female A. hallinani can be differentiated from A. aztecum by the depressed apical rim on T6 only being visible medially and the presence of a short carina above the median emargination (Gonzalez and Griswold 2013). Male A. hallinani can be differentiated from A. aztecum by the broad, dense brush of reddish-brown hairs; the brush of A. aztecum is more pale-colored and sparse. Anthidium hallinani also has a less sharply projected lateral lobes of S6, a more truncate S6 apical margin medially, and a broader S8 apical process (Gonzalez and Griswold 2013).
Anthidium hallinani adults have been recorded in flight from November to March; however, a single record was recorded in September. Peak activity occurs from the last half of January to the first half of February (Gonzalez and Griswold 2013).
Anthidium hallinani have been observed visiting Stylosanthes guianensis (Fabaceae) and Hyptis sp. (Lamiaceae) (Gonzalez and Griswold 2013).
Nesting behavior is unknown.
Anthidium hallinani occur in Costa Rica, Panama, and Chiapas, Southern Mexico. They are found primarily in the Chiapas Depression, dry forests in Central American and Panama, pine-oak forests in Central America, and moist forest habitats (Gonzalez and Griswold 2013). None are known to occur in the U.S. or Canada.