A revision of the cleptoparasitic bee genus Epeolus Latreille for Nearctic species, north of Mexico (Hymenoptera, Apidae)

Abstract

Herein, the cleptoparasitic (cuckoo) bee genus Epeolus (Hymenoptera: Apidae) is revised for species occurring in North America, north of Mexico, and an updated checklist of all species known to occur in Canada and the United States of America is provided with comprehensive descriptions, diagnoses, and a single dichotomous key (using the same couplets for both sexes) to aid in their identification. To increase their recognition among North American naturalists, English common names are also proposed for all North American Epeolus. A total of 43 species is confirmed as present in the region, 15 of which are newly recognized. The following new species are proposed based on unique morphological (and in most cases also molecular) attributes: E. andriyi sp. n., E. attenboroughi sp. n., E. axillaris sp. n., E. basili sp. n., E. brumleyi sp. n., E. chamaesarachae sp. n., E. deyrupi sp. n., E. diadematus sp. n., E. ferrarii sp. n., E. gibbsi sp. n., E. inornatus sp. n., E. nebulosus sp. n., E. packeri sp. n., E. splendidus sp. n., and E. tessieris sp. n. Of the 15, six (E. axillaris, E. brumleyi, E. chamaesarachae, E. diadematus, E. splendidus, and E. tessieris) were identified as new species under different names (nomina nuda) in an M.Sc. thesis by Richard L. Brumley in 1965, but until now they have not been formally described. Detailed morphological comparisons with some evidence from DNA barcoding support the following synonymies, one of which C was first proposed by Brumley (1965): a) E. melectimimus Cockerell and Sandhouse, syn. n., under E. asperatus Cockerell; b) E. crucis Cockerell, syn. n., under E. compactus Cresson; c) E. mesillae palmarum Linsley, syn. n., under E. mesillae (Cockerell); and d) E. weemsi Mitchell, syn. n., and e) E. vernalis Mitchell, syn. n., under E. ilicis Mitchell. Only one member of the almost entirely Neotropical “Trophocleptria group” (Epeolus bifasciatus Cresson) is confirmed as occurring north of Mexico, and is widespread East of the Rocky Mountains. Known floral associations are indicated for each species, as are suspected or known host species of Colletes Latreille. Evidence is presented that suggests further investigation into the possible synonymy of Colletes wickhami Timberlake under C. scopiventer Swenk is warranted.

Floral resource diversity drives bee community diversity in prairie restorations along an agricultural landscape gradient

“…Bee classification followed Michener (2007), except for Dorchin, López‐Uribe, Praz, Griswold, and Danforth (2018) for Eucera and Gibbs, Packer, Dumesh, and Danforth (2013) for Lasioglossum . We identified bees to species level using published keys and revisions (Arduser, 2015; Coelho, 2004; Dumesh & Sheffield, 2012; Gibbs, 2010, 2011; Gibbs et al., 2013; Onuferko, 2018; Portman, Lane, Pardee, & Cariveau, in press; Rehan & Sheffield, 2011; Rightmyer, 2008). For a full list of bee species and taxonomic resources, see Table .…”

Brachymelecta Linsley, 1939, previously the rarest North American bee genus, was described from an aberrant specimen and is the senior synonym for Xeromelecta Linsley, 1939

“…Species limits were established using an integrative biosystematics approach, in which both morphological and molecular evidence were considered (e.g., as in Gibbs 2009Gibbs , 2010Gibbs , 2011Rocha-Filho & Packer 2015;Monckton 2016;Onuferko 2017Onuferko , 2018Onuferko , 2019Ferrari 2017Ferrari , 2019. Specifically, external morphology was compared among representatives of the studied species/forms of Melectini (under a Leica M80 stereo microscope).…”

“…Terminology follows Michener (2007) except, following Prentice (1998) and other recent papers (e.g., Mir Sharifi et al 2019), the frons, gena, and vertex are herein referred to as the frontal, genal, and vertexal areas, respectively, since these features are not clearly demarcated on the surface of the head. Additional terms used in this study, some of which are taken from previous taxonomic studies of cleptoparasitic bees (Rightmyer 2008;Onuferko 2017Onuferko , 2018Onuferko , 2019 are redefined here as follows: in the species descriptions, length refers to measurements made along the longitudinal axis of a bee and width refers to measurements made along the lateral axis, except that breadth is used rather than length in reference to the longitudinal extent of the bands of short, appressed branched pale hairs (fasciae) present on the metasomal terga of most of the treated species. Genal beard refers to the long, erect hairs occupying much of the genal area.…”

“…The redescription of each species is based on the primary type specimen (holotype or lectotype); however, since the holotype of X. alayoi was unavailable for detailed study under the microscope, measurements of anatomical features presented for that species are based on a non-type female specimen (the only one available for study). Redescriptions follow the format of Onuferko (2017Onuferko ( , 2018Onuferko ( , 2019, with a full description provided for the sex that corresponds to the primary type specimen and a shorter description provided for the sex opposite that of the primary type that lists only key differences. Full descriptions for both sexes are not provided since the studied species do not exhibit marked sexual dimorphism except in the terminalia and usual secondary sexual characters (number of flagellomeres; presence of deep, pit-like flagellar sensoria in males but not females; and number of metasomal segments).…”

Monotypic no more – a new species of the unusual genus Schwarzia (Hymenoptera, Apidae, Biastini)

“…An interesting and prominent morphological difference between S. emmae and S. elizabethae are the finely punctate supraclypeal protrusions of S. emmae, which are entirely absent in S. elizabethae . Very similar morphological structures occur in several not closely related bees, such as diverse species of Epeolus Latreille, 1802(e.g., E. bifasciatus Cresson, 1864, E. boliviensis Friese, 1908Onuferko 2017, Onuferko 2018, Holcopasites (H. bigibbosus Hurd & Linsley, 1972) or Chilicola Spinola, 1851 (e.g., Chilicola obesifrons Packer, 2007;Packer and Genaro 2007). Certain species of the Coelioxys Latreille, 1809 subgenera Synocoelioxys Mitchell, 1973(e.g., Coelioxys apacheorum Cockerell, 1900, Coelioxys texana Cresson, 1872 and Glyptocoelioxys Mitchell, 1973 bear granulose swellings around the median ocellus, which are similar in surface structure to protrusions of aforementioned taxa.…”