Submitted to: Zoological Journal of the Linnean Society
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: December 30, 2012
Publication Date: June 3, 2013
Citation: Gonzalez, V.H., Griswold, T.L. 2013. Wool carder bees of the genus Anthidium in the Western Hemisphere (Hymenoptera: Megachilidae, Anthidiini) with a phylogenetic analysis of the subgenerea. Zoological Journal of the Linnean Society. 168(2):221-425. Interpretive Summary: Bees are among the most important pollinators of flowering plants in most ecosystems. Recent concerns about population declines have highlighted the need for a better taxonomic understanding of native bees in order to assess the status of pollinators and pollination services. This work is a comprehensive, broadly comparative study on the diversity, biology, distribution, and evolution of bees of the genus Anthidium. These bees are commonly known as wool carder bees because their cotton-like nest cells that they create for their offspring are made of plant hairs. Anthidium is a diverse group containing more than 150 species worldwide. In this paper we examine the diversity of Anthidium in the Americas based on the study of external morphological characteristics of thousands adult bees deposited in major national and international natural history museums. We present descriptions, illustrations, and identification guides for all 92 species found from Canada to Argentina, including 21 new species to science. For each species we provide information on the distribution, nesting habits, parasites, and plants used either as food or as nesting material. Additionally, we formulate hypotheses on their relationships and discuss possible origins of the American species as well as the evolution of some morphological characteristics associated with pollen and oil collecting from plants.
Technical Abstract: Bees are among the most important pollinators of flowering plants in most ecosystems. Recent concerns about population declines have highlighted the need for a better taxonomic understanding of native bees in order to assess the status of pollinators and pollination services. The genus Anthidium Fabricius is one of the most diverse groups in the family Megachilidae, containing more than 150 species worldwide. Herein, the Western Hemisphere species of this cosmopolitan genus are revised. A neotype for A. emarginatum Say and lectotypes for 16 names are designated; five names are relegated to synonymy, three names are revalidated, previously unknown males are described and 21 new species are proposed. All 92 recognized species in the New World, including the two adventive species A. oblongatum and A. manicatum, are described and illustrated. Identification keys as well as information on the distribution, seasonality, nesting biology and host plants are given. The relationships of the Anthidium subgenera and all New World species are explored using a cladistic analysis based on adult external morphological characters. The subgenus Callanthidium renders Anthidium s. str. paraphylectic in the analyses and is therefore synonymized here. The resulting phylogenetic hypothesis is used to examine possible biogeographical patterns, origins of the Western Hemisphere fauna and the evolution of morphological traits associated with foraging for pollen from nototribic flowers and exudates from glandular trichomes.