Anthophora (Micranthophora) erythrothorax Michener 1936
Creators: name: Orr, Michael C.
name: Pitts, James P.
name: Griswold, Terry
Publisher: name: Zenodo
Year: 2018
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hymenoptera
Apidae
Anthophora
Anthophora erythrothorax

description: Anthophora (Micranthophora) erythrothorax Michener, 1936
(Figs. 33C, 40B, 45B, 50B, 55B, 60B, 65B, 70B, 75B)
Anthophora erythrothorax Michener, 1936: 93 (holotype: ♀; Mill Creek, San Bernardino Mountains, CA, USA; coll. C.D. Michener, 31 Aug. 1930; CASENT, type 8742).
Diagnosis. Females may be determined by the following character combination: galea with long setae bent toward tip and surface moderately tessellate, with weak reflections (Fig. 33C); supraclypeal maculation absent; T5 without appressed setae; and anal fimbria dark brown to black. Males may be determined by the following character combination: galea moderately tessellate, with relatively weak reflections if any; labral rim tridentate; underside of scape fully maculated; tergal rims translucent, light brown; T2–T4 with apical appressed setal bands; T5–T6 lacking any appressed setae, although some setae of intermediate thickness may be present they are much slimmer than the appressed setae of the preceding terga; T7 lacking medial longitudinal carina, lateral projections sharp, and medial projections slender and almost as sharp as lateral projections (Fig. 60B).
Male description. Head: Facial maculations richly yellow. Galea reaching about rear of foretrochanter or farther in repose; light to medium brown; moderately to strongly tessellate, with weak if any reflections. Mandible with inferior tooth ovular to weakly triangular, running roughly parallel to or slightly angled off main blade; maculated from base to near start of inferior tooth (Fig. 50B). Labral rim tridentate. Clypeal maculation a thick band, usually nearly reaching lateral sides, slightly reaching upward medially but usually not exceeding half of clypeal height (Fig. 50B); punctation variable, slightly to moderately sparser within maculation than without. Paraocular area usually immaculate; with small dot at most. Supraclypeal area immaculate. Scape maculated; fully along length below. Mesosoma: Scutum shiny; with impunctate areas, sometimes obscured by flattened setae. Tegula translucent to transparent, medium brown to orangish light brown. Basitibial plate usually present; weak, often just delimited along distal rim, may be obscured by setae. Metasoma: T1 with weak apical appressed setal band, due to sparser basal appressed setae medially; T2–T4 with thinner apical appressed setal bands, only vaguely undulate if at all; T5–T6 without appressed setae or strongly reduced. Terga moderately to strongly tessellate between punctures, with weak reflections; not often apparent through appressed setae. Tergal rims mostly transparent, tan to light brown. Male T7 (Fig. 60B) without or with extremely weak and obscure medial longitudinal carina; lateral projections strongly recurved, sharp; medial projections long and thin but apically rounded. Male S5 (Figs. 38A, 38C) setal arrangement unremarkable, without large, distinctive patches, at most longer along rim. Male S6 (Fig. 38A) clearly medially emarginate. Male S7 (Fig. 65B) with setae absent or nearly so around midpoint of length; widening from midpoint to tip, apical half widest near rounded lateral tips; apical half resembling owl head, rim roughly flat, with shallow medial emargination. Male S8 (Fig. 70B) lateral projections distinct; medial projection narrowing to tip, apically emarginate. Male genital capsule (Fig. 75B) with outer corners, where gonocoxite tips curve inward, marked by obvious flange of about 90 degrees or greater, best seen in profile; from corner to apex, in profile, gonocoxite relatively unmodified, concave or straight; tip, in profile, rounded and moderately curved ventrally, with minor dorsal projection clearly pointed; gonostylus tip position significantly exceeding that of gonocoxite, measured from above along primary axis of latter. Pubescence: See Fig. 55B. Appears brown to somewhat grayish overall, in part due to terga basal zones. Setae generally yellow to tan, becoming whiter toward venter, except as follows: with strong dark intermix on vertex and scutum; leg inner faces orangish; sterna light.
Female similar to male, except: Head: Galea often darker brown; long setae present and bent toward galeal apex near tips (Fig. 33C). Mandible with inferior tooth somewhat ridge-like but expanded near tip, slightly angled off main blade (Fig. 40B). Labral rim rounded; fully maculated. Clypeal maculation larger, filling nearly all of clypeal height medially where tallest at middle (Fig. 40B). Scape immaculate. Mesosoma: Midtibial spur apically curved; orange. Basitibial plate circular distally, teardropped overall. Metasoma: T1 with weak apical appressed setal band, due to sparser basal appressed setae medially; T2–T4 with thin to moderately broad, undulate appressed setal bands, T3 sometimes and T4 often interrupted medially; T5 without appressed setae. Terga often less tessellate. T4 impunctate rim of moderate to extended length medially, usually only vaguely and widely triangular. Anal fimbria strongly triangular, covering third to clearly under half of T5 length medially. Pubescence: See Fig. 45B. Hindbasitarsal brush dark brown; tergal basal zones dark; anal fimbria dark brown to blackish; S5 apicomedially dark but often obscured by some light.
Distribution. See Fig. 13. Apparently rare. Present in USA: California; Mexico: possibly Baja California Norte. Found almost exclusively in mid-elevations or foothills of Southern California. Ecoregional habitance is as follows, based on 31 specimen records: 5 ecoregions total: California montane chaparral and woodlands (20=64.5%), Mojave Desert (6=19.4%), Sonoran Desert (2=6.5%), Sierra Nevada forests (2=6.5%), California coastal sage and chaparral (1=3.2%).
Phenology. Recorded from August–October, primarily August–September. Few records preclude certainty, likely univoltine.
Nesting biology. Unknown.
Floral specialization. Likely specialist on Asteraceae, given known floral visits and preferences of closely related species. Modified pollen-gathering galeal setae may improve efficiency near start of bloom when flowers are less open (Fig. 33c). Primary recorded visits by seven females include: Family Asteraceae (100%); Genus Corethrogyne (29%), Ericameria (29%), Heterotheca (29%), Viguiera (14%); Species Corethrogyne filaginifolia (29%), Ericameria teretifolia (29%), Heterotheca villosa (29%), Viguiera parishii (14%). Nine total floral records include: Asteraceae (2 ♂ 7 ♀): Corethrogyne filaginifolia 2 ♀, Ericameria teretifolia 2 ♀, Heterotheca villosa 1 ♂ 2 ♀, Rudbeckia californica 1 ♂, Viguiera parishii 1 ♀.
Comments. One female specimen with little wear is known without galeal setae, suggesting either that this specimen was aberrant or that the galeal setae incur more wear than elsewhere.
Specimens examined: USA: CALIFORNIA: Kern County: Valley Vista Camp [may be Chula Vista Camp]: 1 ♂, 9 Sep 1971, J.A. Honey; Los Angeles County: Big Rock Creek, south fork: 4 ♀, 30 Sep 1965, R. R. Snelling; South Fork, Big Rock Creek: 1 ♂, 30 Sep 1963, R. R. Snelling; Vasquez Rocks Natural Area Park: 2 ♂ 6 ♀, 13–17 Aug 1973, P.H. Sullivan; Riverside County: Anza: 1 ♀, 13 Oct 2014, collector unknown; Anza-Borrego: 1 ♀, 13 Oct 2014, K.J. Hung; 1 ♀, 10 Oct 2015, K.J. Hung; San Bernardino County: 4 mi N Warrens Well [= Warners Well]: 1 ♀, 22 Oct 1937, P.H. Timberlake; Fallsvale: 1 ♀, 8 Sep 1984, K.W. Cooper; Mill Creek, Mill Creek Canyon, San Bernardino Mountains, San Bernardino National Forest: 1 ♀, 7 Sep 1931, C.D. Michener; 2 ♀ 1 ♀, 5 Sep 1937, P.H. Timberlake; 1 ♂, 10 Aug 1957, P.H. Timberlake; Valley of the Falls: 2 ♀, 11 Aug 1935, P.H. Timberlake; 1 ♂, 11 Aug 1935, Timberlake; 2 ♀, date unknown, collector unknown; Tulare County: Tokopah Valley, Sequoia National Park: 1 ♀, 23 Aug 1933, C.D. Michener; 1 ♂, 29 Aug 1933, C.D. Michener.
description: Published as part of Orr, Michael C., Pitts, James P. & Griswold, Terry, 2018, Revision of the bee group Anthophora (Micranthophora) (Hymenoptera: Apidae), with notes on potential conservation concerns and a molecular phylogeny of the genus, pp. 1-193 in Zootaxa 4511 (1) on pages 57-59, DOI: 10.11646/zootaxa.4511.1.1, http://zenodo.org/record/3770979