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Mission, Texas


Mission, Texas

Melissodes tepaneca; Copyright 2020 Paula Sharp


Genus Melissodes


Long-horned bees belong to the tribe Eucerini and have unusually long antennae – hence the name "long-horned".  Eucerini serve as essential pollinators for multi-million-dollar crop industries and include, among others, Svastra long-horned bees, instrumental in sunflower production; and Eucera long-horned bees that serve as key pollinators of melons and squash. The tribe Eucerini also includes Melissodes, a genus of irreplaceable pollinators of garden flowers, native wildflowers and sunflower crops.   

All Melissodes are ground-nesters.  The bees carve holes in the earth, where they construct individual nests containing brood cells lined with a waxlike material, each holding one egg and a single pollen ball.  The nests, which may be isolated or built in  groups, are frequently hidden under brush. 


Female Melissodes tend to be easiest to find when they are out pollinating flowers.  Males often rest hanging by their jaws from the stems of plants. In early morning, it is sometimes possible to surprise whole groups of male long-horned bees sleeping together in this manner. 


Melissodes of the Lower Rio Grande Valley tend to be most abundant in summer and fall.  Many, such as the mournful longhorned-bee (Melissodes tristis) and Tepanec longhorned bee (Melissodes tepaneca), are generalist pollinators.  Some, like the coreopis long-horned bee (Melissodes coreopsis) show a preference for aster-family flowers; others specialize on such flowers as thistles, mallow and evening primrose. 

General traits of Melissodes

Melissodes are robust, medium-sized bees with hairy heads and bodies.  Females have prominent, bushy pollen-collecting scopal hairs on their back legs.  Males have narrower builds than females; lack bushy hind-leg hairs; and usually sport much longer antennae.  Both female and male Melissodes may have striking green or blue eyes; eye color within a given species may vary according to gender.  In many Melissodes species, males have pale markings on the clypeus (the part of the face situated above the mandibles).

Texas has an exceptionally rich diversity of Melissodes long-horned bees.  Melissodes of at least three distinct subgenera, each with its own special characteristics, are found within the Lower Rio Grande Valley.  These subgenera include Eumelissodes, Melissodes and Tachymelissodes.*



* A recent phylogenic study of long-horned bees submerges the subgenus Tachymelissodes in the larger subgenus Apomelissodes.  See Freitas et al.  (2023).



Melissodes; Copyright 2020 Paula Sharp

A female Melissodes long-horned bee:  note the bushy scopal hairs on the bee's back legs.

Melissodes tepaneca; Copyright 2020 Paula Sharp


Order:   Hymenoptera

Family:   Apidae

Subfamily:  Eucerinae

Tribe:  Eucerini

Genus:   Melissodes
Species shown below:

    Melissodes (Eumelissodes) coreopsis (coreopsis long-horned bee) 

    Melissodes (Eumelissodes) tristis (mournful long-horned bee)
    Melissodes (Melissodes) tepaneca (Tepanec long-horned bee)
    Melissodes (Tachymelissodes/Apomelissodes) opuntiellus (prickly pear long-horned bee)

A male Tepanec long-horned bee of the subgenus Melissodes:  note the very long "horns" (antennae) and the yellow clypeus.

Long-horned Bee Species of the Lower Rio Grande Valley

Tepanec Long-horned Bee
Melissodes (Melissodes) tepaneca

Family:  Apidae

Size:  11 mm (male); 12 mm (female)

Food plants in the LRGV 

Retama (a kind of Palo Verde)

(Parkinsonia aculeata)
Plant family:  Fabaceae

Golden dewdrops

(Duranta erecta)
Plant family:  Verbenaceae

Common sunflower
(Helianthus annuus)
Plant Family:  Asteraceae

When seen:

September - April, 2018 -2023
National Butterfly Center

Found throughout Cameron, Hidalgo & Starr Counties

Melissodes tepaneca; Copyright 2020 Paula Sharp

A female Tepanec longhorn bee (Melissodes tepaneca)

Melissodes tepaneca; Copyright 2020 Paula Sharp

A male Tepanec longhorn bee 

Little Prickly Pear Long-horned Bee
Melissodes (Tachymelissodes) opuntiellus

or Melissodes (Apomelissodes) opuntiellus

Family:  Apidae

Size:  8 mm (female and male)

Associated plants at NBC:  

Red prickly poppy

(Argemone sanguinea)
Plant family:  Papaveraceae

Texas prickly pear

(Opuntia engelmanii)
Plant family:  Cactaceae

Tea bush

(Melochia tomentosa)
Plant family:  Malvaceae (formerly Sterculiaceae)

When seen:  March-April 2019, 2021 

Melissodes long-horned bees
Melissdes opuntiellus; Copyright 2023 Paula Sharp

A female Melissodes opuntiellus

Melissodes opuntiellus; Copyright 2023 Paula Sharp

A male Melissodes opuntiellus

A note on Melissodes opuntiellus:  The species name "opuntiellus" is a reference to Opuntia, the scientific name for prickly pear cactus.  The Latin suffix "ellus" is a diminutive ending.  Thus this bee's name might translate as "the little prickly pear bee".  During spring in the Lower Rio Grande Valley, male Melissodes opuntiella appear in large numbers on the flowers of Texas prickly pear cactus (Opuntia englemannii).

This species was first described by the entomologist T. D. A. Cockerell in 1911, in a one-page article  titled "Some New Bees from Flowers of Cactaceae," shown below left, which appeared in Volume 35 of The Canadian Entomologist.

Prickly poppies in the Lower Rio Grand Valley begin flowering just before the bloom period of Texas prickly pear cactus.  Male Melissodes opuntiellus   appear on prickly poppy (Argemone sanguinea) in mid-March at the NBC and the surrounding area. 

We have noted that various genera of male bees that feed on prickly pear flowers (including Lithugopsis and Diadasia)  appear to use prickly poppies in the spring for shelter, without feeding on them.  (Male bees drink nectar but do not gather pollen; prickly poppies produce pollen but very little nectar.) Possibly, the bees choose the poppies to rest in because they are comfortable and roomy and provide protection from wind and rain.

Females of this species have been documented on an array of plants including mallows and palo verde.  In 1980, during a survey of sunflower pollinators, entomologists Hurd and LaBerge observed this species foraging on sunflowers.  At the NBC, female bees have appeared on prickly poppies, prickly pear cactus and teabush.

Associated flora:


(Heterotheca subaxillaris)

When seen:

October 2023

Estero Llano Grande SP

Weslaco - Hidalgo Co.


Coreopsis Longhorn Bee
Melissodes (Eumelissodes) coreopsis

Family:  Apidae

Size:  8.5 - 11 mm (male)

10 - 11 mm (female)

Melissodes coreopsis; Copyright 2023 Paula Sharp

A female coreopsis longhorn bee (Melissodes coreopsis)

Melissodes coreopsis; Copyright 2023 Paula Sharp

A male coreopis longhorn bee

Melissodes coreopsis; Coreopsis longhorn bee (male); Copyright 2022 Sharp-Eatman Nature Photography

Dark labrum and mandibles of male bee

Mournful Long-horned Bee

or Dark-faced Long-horned Bee
Melissodes (Eumelissodes) tristis

Family:  Apidae

Size:  9-12 mm  (male)

          10-14 mm (female)

Associated plants at NBC:  


Shrubby blue sage

(Salvia ballotiflora)

Plant family:   Lamiaceae


Honey mesquite

(Prosopis glandulosa)

Plant family:   Fabaceae

When seen:   
April 2019, March 2020 

Melissodes tristis; Copyright 2020 Paula Sharp

A female Melissodes tristis on shrubby blue sage 

Melissodes tristis; Copyright 2020 J. A. Winget

A male Melissodes tristis  (Photograph copyright 2017 J. A. Winget)

Melissodes tristis; Copyright 2020 Paula Sharp

A female Melissodes tristis long-horned bee        

As noted above, longed-horned bees of the subgenus Eumelissodes often specialize in pollinating composite flowers of the family Asteraceae such as sunflowers and daisies.  The mournful long-horned bee, however, is a prodigious generalist that has been documented visiting the flowers of more than twenty plant families. 


According to entomologist Wallace E. LaBerge, author of a comprehensive 1961 study of the genus Melissodes, the mournful long-horned bee is the most polyletic species of the subgenus EumelissodesMelissodes tristis has a remarkably long flight season, from March through November, and is able to adapt to an array of habitats with very different flora.  LaBerge believed that this species produces as many as three generations per year in Texas.

Female Melissodes tristis appear in late March and early April at the National Butterfly Center as honey mesquite begins to bloom.  Male bees have not been observed to date at the NBC.  (The example shown here of a male bee was contributed to this website by  nature photographer J. A. Winget, who found it in Grand Canyon Village, Arizona).  Melissodes tristis is endemic to much of Texas, and to south central Mexico as far south as the state of Oaxaca.  This species ranges through the southwestern United States and extends from western Oklahoma, Kansas and Nebraska through Colorado, Nevada, Utah, and southern Wyoming, into California and Oregon. 

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

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