Philanthinae

Abstract: Debevec, AH., Cardinal, S & Danforth, BN. (2012). Identifying the sister group to the bees: a molecular phylogeny of Aculeata with an emphasis on the superfamily Apoidea. —Zoologica Scripta, 41, 527–535. The hymenopteran superfamily Apoidea includes the bees (Anthophila) as well as four predatory wasp families (Heterogynaidae, Ampulicidae, Sphecidae and Crabronidae) collectively referred to as the ‘‘sphecoid’’ or ‘‘apoid’’ wasps. The most widely cited studies suggest that bees are sister to the wasp family Crabronidae, but alternative hypotheses have been proposed based on both morphological and molecular data. We combined DNA sequence data from previously published studies and newly generated data for four nuclear genes (28S, long-wavelength rhodopsin, elongation factor-1a and wingless) to identify the likely sister group to the bees. Analysis of our four-gene data set by maximum likelihood and Bayesian methods indicates that bees most likely arise from within a paraphyletic Crabronidae. Possible sister groups to the bees include Philanthinae, Pemphredoninae or Philanthinae + Pemphredoninae. We used Bayesian methods to explore the robustness of our results. Bayes Factor tests strongly rejected the hypotheses of crabronid monophyly as well as placement of Heterogynaidae within Crabronidae. Our results were also stable to alternative rootings of the bees. These findings provide additional support for the hypothesis that bees arise from within Crabronidae, rather than being sister to Crabronidae, thus altering our understanding of bee ancestry and evolutionary history.

Abstract: . The Philanthinae, as treated here, contains the eight valid genera Aphilanthops Patton, Cerceris Latreille, Clypeadon Patton, Eucerceris Cresson, Philanthinus Beaumont, Philanthus Fabricius, Pseudoscolia Radoszkowski and Trachypus Klug. Listropygia Bohart is synonymized with Clypeadon, syn.n. The genera Eremiasphecium Kohl and Odontosphex Arnold are removed from the Philanthinae and regarded as genera incertae sedis within Sphecidae. Analysis of the genera of this redefined subfamily Philanthinae finds two major clades whose monophyly is strongly supported: (Philanthinus+ (Philanthus+Trachypus)) [= Tribe Philanthini] and (Pseudoscolia+ (Cerceris+Eucerceris)) [= Tribe Cercerini]. There is some evidence for the monophyly of Clypeadon+Aphilanthops [= Tribe Aphilanthopini]. Cerceris and Philanthus are inferred to be paraphyletic with respect to Eucerceris and Trachypus, respectively. Philanthinus is removed from the tribe Aphilanthopini and placed in the tribe Philanthini, and the monotypic tribe Pseudoscoliini is synonymized with Cercerini.

Abstract: An aggregation of the philanthine wasp Cerceris fumipennis Say was observed during nest-founding from March 25-31, 1989, at the Archbold Biological Station, Florida. Newly emerged wasps were individually marked and measured for head width. Observa tions of 35 nests over six daily activity periods revealed frequent nest switching and nest usurpation. Larger females displaced smaller females from their nests, and larger females maintained residence longer than smaller females. As a consequence, the average size of females holding a nest increased significantly during the nest-founding phase, but the average size of all females observed at the nest aggregation did not change during the same period. Size therefore predicts a female wasp's likelihood of acquiring and retaining a nest, suggesting that large females are competitively superior to small females during nest founding. In some cases, two females appeared to share a nest, but did not provision