Subfamily Colletinae Lepeletier
Genus Colletes Latreille (15 taxa)
Bees of the genus Colletes are solitary, but sometimes nest
gregariously. These are ground nesting bees that often have prominent nests in
open areas. These are either spring (9 species) or fall (5 species) flying but
one species (C. mandibularis) exhibits two generations and flies in both
spring and fall. In Florida and the south, they are generally lacking during the
summer months of June and July. Most species are polylectic, foraging primarily
on shrubs and trees.
Fifteen to seventeen species, depending on the uncertain taxonomy of three
species, are found in Florida. There is some disagreement on species between
Stephen (1954) and Mitchell (1960). For example, Mitchell separates C.
banksii from C. distinctus while Stephen makes it a synonym. In
contrast, Mitchell synonymizes C. carolinus with his C. distinctus.
All of our species, with two exceptions, are found elsewhere, primarily in the
eastern U.S. but some extending further west. The two endemic species include C.
titusensis, found in the central peninsula, and C. longifacies, found
in the western panhandle and north-central peninsula. Both species have been
described on the basis of 2-3 specimens. One new range extension to Florida is
proposed for C. inaequalis, based on the specimens collected by
Pascarella (unpublished data) in Leon County, Florida. There are no recognized
subspecies but Stephen recognized several species groups.
Key features used in identifying Colletes to species level include,
besides the male genitalia, the presence of a dorsal prominence or horizontal
carina on the mesepisternum and metepisternum (Stephen collectively referred to
these as the metapleura), the malar length vs. malar width, flagellar length vs.
width, hair color, prothoracic spines in females, sterna, and tergum punctation.
Hair color is also used although hair color was found to be highly variable in
many species (Stephen 1954). The horizontal carina character is found below the
wings and can be hard to see. Some species have an orange to yellow edge to the
carina, others just a black prominence, and others no noticeable swelling of
either type.
Key references to Colletes.
Michener, C. D. 2000. Bees of the World. Johns Hopkins University Press,
Baltimore, MD, USA. 913 p.
Mitchell, T.B. 1960. Bees of the Eastern United States. Volume I. North Carolina
Agricultural Experiment Station Technical Bulletin 141, 538 p.
Stephen, W. P. 1954. A revision of the bee genus Colletes in America
North of Mexico (Hymenoptera, Colletidae). The University of Kansas Science
Bulletin 36(1): 149-527.
Key to females (From Mitchell 1960)
- Metapleura each with dorsal prominence or horizontal carina usually with
testaceous rim; malar spaces no longer than one-half as long as broad; last
exposed sternum with apex not depressed..15
Metapluera with no dorsal prominence, or if weak prominence, with carina
curving ventrally well in front of posterior margins; if having metapleural
prominences, then malar spaces as long as broad…2
- Median flagellar segments short, usually one-half to three-fourths as long
as broad when viewed from above; and last exposed sternum with apical
portion strongly depressed with basal arcuate band of overhanging pile; when
apical depression very small, sterna with strong scopa..C. brevicornis
Median flagellar segments usually as long as broad when viewed from above;
last exposed sternum usually lacking depressed apical portion…3
- Mesoscutum and/or scutellum with admixture of black pile…4
Mesoscutum and scutellum with no black pile…12
- Malar spaces at least three-fourths as long as broad…C. longifacies
Malar spaces usually one-half as long as broad or less…5
- First metasomal terga very finely punctate, punctures folliclelike and at
least two puncture widths apart on discal area…C. titusensis
First metasomal tergum deeply punctate, punctures one to one and one-half
puncture widths apart laterally, or punctures fine and contiguous….6
- Posterior basitarsi twice as long as broad, clypeus flattened, obscurely
striately punctate; malar spaces one-third as long as broad..C.
latitarsis
Posterior basitarsi at least three times as long as broad…7
- Prothoracic spines long and sharp, longer than width across base…8
Prothoracic spines short, absent, or obliquely truncate, never terminating
in a needlelike point to edge of head….10
- Fore coxae with long spines, at least as long as broad..C. simulans
Fore coxae lacking spines…9.
- Clypeus long, flat, dull, and roughened; flagellar segments short, about
five-eights as long as broad…C. willistoni
Clypeus short, convex, coarsely punctate with shiny interspaces; flagellar
segments about as long as broad..C. nudus
10. Antennae very short, flagellar segments one-half as long as broad; length
9-10mm..11
Antennae long, flagellar segments as long as broad; length 12-14mm….C.
inaequalis
11. Metasomal terga one to three with distinct narrow preapical groove,
followed by raised flangelike margins; clypeus closely punctate…C.
brevicornis
Metasomal terga one to three with apical margins entire and smooth, broadly
fasciate; clypeus flat, dull, and weakly roughened..C. willistoni
- Prothoracic spines sharp, at least as long as width across base..C.
distinctus
Prothoracic spines short or absent, never as long as width across base…13
- Mesepisterna dull, obscurely or finely and densely punctate; mesoscutum with
pile bright ochreus..C. thoracicus
Mesepisterna rugosely punctate with shiny, although sometimes roughened,
interspaces; pile variable in color….14
- Last metasomal sternum with weak, elevated lateral longitudinal carina
curved medially at apex; second metasomal tergum finely and densely
folliculated; tegulae black..C. distinctus
Last metasomal sternum lacking carinae; second metasomal tergum sparsely
folliculated; tegulae brown hyaline…C. brimleyi
- Metapleural prominence strongly protuberant with a broad rim, abruptly
declivous beneath..16
Metapleural prominence weakly protuberant with a narrow brown to black rim,
shallowly concave beneath…17
- Second metasomal tergum with broad, dense basal fascia, at least as broad as
nonpubescent areas between basal and apical fasciae; first metasomal tergum
finely and densely punctate especially laterally; metasomal terga three to
five with short, white, and semierect pile, giving the surface a whitish
sheen; apical fasciae broad and white; lateral fringes of first metasomal
tergum dense and continuous to apical fascia; mesoscutum with pile white to
ochreus…C. mandibularis
Second metasomal tergum with basal fascia weak or absent, nor more than
one-third as wide as nonpubescent area between basal and apical fascia; first
metasomal tergum with disc sparsely folliculated and shiny; metasomal terga
three to five bare and shiny, occassionally with a few semierect hairs; apical
fascia weak and narrow; first metasomal tergum with lateral fringes weak and
usally not continuous to apical fascia; mesoscutum with pile deep ochreus to
yellow; Second metasomal tergum with a narrow basal fascia; mesepisterna
densely, almost contiguously punctate; propodeum with posterior face smooth,
sparsely punctate; pile of body tinged with fuscous..C. americanus
- Mesoscutum and scutellum with strong admixture of black and dark hairs;
second metasomal tergum with no basal fascia; mesepisterna rugose…C.
thysanellae
Mesoscutum and scutellum with pile entirely light; second metasomal tergum
with strong basal fascia; mesepisterna distinctly punctate…C. speculiferus
For females, C. brevicornis, C.
willistoni and C. distinctus come out twice in
the key.
Key to males (From Mitchell 1960)
- Metapleura each with dorsal prominence or horizontal carina, usually with
testaceous rim, and malar spaces no longer than broad, flagellar segments
longer than broad…13
Metapleura with no dorsal prominence or if weakly prominent with carinae
curving ventrally well in front of posterior margins, if having rimmed
prominence then malar spaces one and one-half times as long as broad…2
- Median flagellar segments usually as long as broad or slightly longer, and
penis valves with broad dorsal and ventral wings…16
Median flagellar segments usually at least one and one-half times as long
as broad; if shorter, penis valves lacking dorsal wing….3
- Mesoscutum, scutellum, or inner orbital margins with varying amounts of
black hair…4
Mesoscutum, scutellum, and inner orbital margins with light hair…9
- Malar spaces at least as long as broad, usually longer…5
Malar spaces no longer than three fourths as long as broad…6
- Propodeum with posterior face outside of triangle rugose above; metasomal
terga with discs having abundant short, erect, black pile; thorax with pile
long, dense, and ochreus; seventh ventral plates with lateral lobe short and
at tijmes partially fused to median..C. thoracicus
Prododeum with posterior face outside of triangle dull and roughened;
metasomal terga with discs having pile white to pale grey; thorax with pile,
long, fine, and pale grey on periphery; seventh ventral plates tripartite
apically, lateral lobes long and broadly separated from median lobe…C.
inaequalis
- Posterior basitarsi short, no more than two and one-half times as long as
broad..C. latitarsis
Posterior basitarsi about four times as long as broad…7
- Prothoracic spines long and sharp, at least as long as width across base…8
Prothoracic spines short, vestigial, or obliquely truncate…C.
inaequalis
- Vertex and mesoscutum with abundant black pile; length 11-14 mm, body
coarsely punctate…C. nudus
Vertex with light pile; mesoscutum with but a few black hairs; length 8-10
mm…. C simulans
- First metasomal terga shiny, impunctate, or, if punctate, with a few
scattered folliclelike punctures especially laterally…10
First metasomal terga closely punctate, punctures no more than two puncture
widths apart…12
- Flagellar segments short, as long as broad; malar spaces linear…C.
titusensis
Flagellar segments about one and one-half times as long as broad; malar
spaces at least three-eights as long as broad…11
- Malar spaces three-fourths as long as broad; seventh ventral plates with
discs broader than long, weakly quadrate…C. brimleyi
Malar spaces three-eigths as long as broad; seventh ventral plates longer
than broad, roughly triangular…C. distinctus
- Metasomal tergum two uniform from base to apex, not depressed basally..C.
thoracicus
Metasomal tergum two depressed basally, with or without basal fasciae…C.
simulans
- Lower edge of metapleural prominence weakly protuberant with a narrow rim
which projects laterally…14
