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Colletes texanus;  Copyright 2020 Paula Sharp

A male Texas Cellophane bee

Colletes texanus was named in 1872 by entomologist Edward Townsend, whose description of the species was based on a female bee found in Comal County.  Within the United States, the Texas Cellophane bee is found nearly exclusively in Texas.  It has been documented in recent years in Cameron, Dallas, Hidalgo and Travis Counties.

Pale-gold Cellophane Bee

Colletes mandibularis

Family:  Megachilidae

Size:  9 mm (female) 

          7-8 mm (male)


Associated plants:

Arkansas dozedaisy

(Aphanostephus skirrhobasis)
Cowpen daisy

(Verbesina encelioides)

Prairie broomweed

(Amphiachyris dracunculoides)

Plant family:  Asteraceae


When and where seen:

​May 2021

El Mesteno Ranch

Puerto Rico (Hidalgo Co.)

Bahia Grande NWR

Brownsville (Cameron Co.)

June 2021

Campos Viejos Ranch

Rio Grande City (Starr Co.)

Colletes mandibularis; Copyright 2023 Sharp-Eatman Nature Photography

A female Colletes mandibularis

Colletes mandibularis; Copyright 2023 Paula Sharp

A female Colletes mandibularis

Colletes mandibularis is a petite cellophane bee with a head and thorax covered with blond and ivory hairs, and an abdomen banded by beige or ivory hairs. Females’ hind-leg scopal hairs are long and pale.  The relatively small size of this cellophane bee and its general pale-gold coloring make it distinctive.  Colletes mandibularis is an aster-family specialist.  In the Valley, this bee is usually found on small-flowered Asteraceae.  


Mission, Texas

Colletes birkmanni; Copyright 2023 Paula Sharp



Genus Colletes

Bees of the genus Colletes line the cells of their nests with a waterproof material which, when dry, resembles clear plastic.  Accordingly, they are sometimes called “cellophane bees”  or, alternately, “polyester bees”.   Cellophane bees are equipped with unusual forked tongues, which they use to paint the plastic-like material onto their nest walls in order to keep their nests dry.  The bees produce the material from a special abdominal organ called the Dufour’s gland, named after French naturalist Léon Jean Marie Dufour, who first recorded his fascination with the bees’ fabrication of plastique in 1835. 


Cellophane bees also spray their egg-cell walls with a natural fungicide and bacteriacide, linalool, secreted from a gland in the bees' mandibles.  After coating their cells, the bees fasten their eggs onto the cell walls rather than leaving them on nest floors where moisture might collect.  The bees provision their cells by mixing pollen and nectar together to make a liquid “bee bread” for their offspring; these provisions are stored in cellophane sacs that look a little like elongated plastic sandwich bags.  The special measures taken by the bees to protect their eggs against water and fungus allow them to build nests near stream banks and other areas with wet soils.


Cellophane bees are solitary.  They construct individual nests in the ground, excavating tunnels that exit through small round holes.  Despite their solitary status, the bees tend to build their nests near one another.  Groups of nesting cellophane bees sometimes number into the tens of thousands.  These bees, however, are non-aggressive and do not form swarms.  They are important pollinators of spring trees, crops and wildflowers. 

The nests of cellophane bees are parasitized by cuckoo bees in the genus Epeolus, which are sometimes called "cellophane cuckoo bees".  Epeolus sneak into the egg chambers of cellophane bees and deposit their own eggs there.  When the cuckoo larvae hatch, they kill off the cellophane bee young and eat the food stores left by the mother cellophane bee for her own offspring.

​​​Identification Information

Cellophane bees are about the size of honey bees (or slightly smaller or slightly larger).  They are hairy bees:  their thoraxes are usually covered with pale, brown or rust-colored  hairs; and their abdomens are often dark and banded with pale hairs.


The faces of cellophane bees are heart-shaped -- that is, a cellophane bee's eyes slant toward one another, and its head tapers downward toward its mandibles.  Cellophane bees' faces are usually covered with pale or light-brown hairs, and their antennae are medium-length.  Female cellophane bees carry pollen on the upper parts of their hind legs. 

Species identification of cellophane bees often hinges on such traits as size; geographic location; the time of year they emerge; the color of hairs on the thorax and head; the width of the hind-leg basitarsi; and the appearance of the bands of pale hair on the bee's abdomen.

Colletes in nest; Copyright 2023 Paula Sharp

A cellophane bee peering from its nest hole

An aggregation of cellophane bee nests

The heart-shaped face of a cellophane bee


Order:   Hymenoptera

Family:   Colletidae

Genus:   Colletes
Species shown here:

     Colletes birkmanni

     Colletes intermixtus

     Colletes mandibularis

     Colletes swenki
     Colletes texanus


Cellophane Bee Species of the National Butterfly Center

Birkmann's Cellophane Bee
Colletes birkmanni

Family:  Colletidae
Size:  12 mm (female)

          9-10 mm (male)

Associated plants at NBC: 

Woolly Croton

(Croton capitatus)
Plant Family:  Euphorbiaceae

Seaside goldenrod

(Solidago sempervirens)
Plant Family:  Asteraceae

When seen:

November 2018
October & November 2019

Colletes birkmanni cellophane bee - (c) Copyright 2018 Paula Sharp

A female Birkmann's cellophane bee (Colletes birkmanni)

Colletes birkmanni - (c) Copyright 2019 Paula Sharp

A male Birkmann's cellophane bee (Colletes birkmanni)

Colletes birkmanni is a medium-sized bee with a dark abdomen boldly striped with white hairs.  The female bee shown here has thorax hairs that are a light rust color; a face covered with white hairs; and a dark abdomen with bold white bands. The male bee is much paler:  it has exuberant white hairs on its face and thorax and white bands on its abdomen.

​​According to John L.  Neff, Director of the Texas Melittological Institute, Birkmann's cellophane bee is common in south Texas. Nonetheless, there has been little written about its nesting behavior or biology.  Neff reports that the species is bivoltine -- that is, there are two crops of of the bee each year, with fall and spring generations.  Birkmann's cellophane bee is a generalist pollinator commonly found feeding on plants in the family Asteraceae. 


The female bee shown here appeared at the National Butterfly Center in November 2018, feeding on woolly croton near an irrigation canal.  In November 2019, both male and female bees were found foraging on seaside goldenrod in the front garden of the National Butterfly Center.

Food plants at NBC:  
Purple groundcherry

(Quincula lobata)
Plant Family:  Solanaceae

When seen:  April 2019

Swenk's Cellophane Bee
Colletes  swenki

Family:  Colletidae

Size:  11 mm (female)

Colletes swenki; (c) 2019 Paula Sharp

A female Swenk's cellophane bee (Colletes swenki)

Purple groundcherry (Quincula lobata)

Plants of the nightshade family Solanaceae require "buzz pollination," because their pollen is trapped tightly within the anthers of their flowers.  Bees known as buzz pollinators (or vibratile pollinators) have the ability to vibrate their flight muscles while grasping a flower:  this shakes pollen loose from the anthers in a manner commonly compared to jiggling a salt shaker to dislodge salt.  Vibratile pollinators exist in several bee families.


Three of the cellophane bees featured here are noisy buzz pollinators that visit Solanaceae native to the Valley:  Swenk's cellophane bee pollinates purple groundcherry (Quincula lobata) and prostrate ground cherry (Chamaesaracha coniodes).  The Texas cellophane bee featured below visits downy ground cherry (Physalis pubescens).  The intermixed cellophane bee visits silverleaf nightshade (Solanum elaeagnifolium).

The female Swenk's cellophane bee shown here appeared at the National Butterfly Center in April 2019.foraging on purple groundcherry.  Entomologist Myron H. Swenk first described Colletes swenki after examining specimens found in Texas in the fifties.  Colletes swenki is chiefly a Texas bee.  It has been recorded in the counties of Bexar, Cameron, Hidalgo, Jim Wells, Kerr, Maverick, Shackelford, Travis and Val Verde. 

Associated plant

Downy ground cherry

(Physalis pubescens)
Family:  Solanaceae

When seen:

March  2020

Texas Cellophane Bee
Colletes texanus 

Family:  Colletidae

Size:  7-8 mm (male)
         9 mm female​

A male Colletes texanus (Texas cellophane bee) - (Copyright Paula Sharp 2020)

A male Texas cellophane bee (Colletes texanus) on physalis

Intermixed Cellophane Bee

Colletes mandibularis

Family:  Megachilidae

Size:  10 - 12 mm (female) 

          9 - 10 mm (male)          

Associated flora:

Silverleaf nightshade
Solanum elaeagnifolium

Plant family:  Solanaceae


When and where seen:

​May 4, 2021

McAllen Nature Center

McAllen (Hidalgo Co.)

Colletes intermixtus; Copyright 2023 Paula Sharp

A female intermixed cellophane bee (Colletes intermixtus)

This species ranges from the west coast to east Texas.  Within Texas, it appears as far north as Dallas County.  The female bee shown here appeared at Quinta Mazatlán (Hidalgo Co.) in early May, 2021. Colletes intermixtus has been reported in Cameron County.

As noted, within the Lower RIo Grande Valley, Colletes intermixtus is a buzz pollinator of nightshade.  This species has been documented visiting a variety of other plants, however, among them large-flowered Asteraceae, huisache (Vachellia farnesiana), whitebrush (Aloysia gratissima) and lemon beebalm (Monarda citriodora).

CITE THIS PAGE:  Sharp, Paula and Ross Eatman.  "Colletes."  Wild Bees of the National Butterfly Center of Mission, Texas. 15 Jan. 2019,  Accessed [day/month/year guide accessed].

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