Euglossini
Encyclopedia
Euglossine bees, also called orchid bees, are the only group of corbiculate
bees whose non-parasitic members do not all possess eusocial behavior
. Most of the species are solitary, though a few are communal, or exhibit simple forms of eusociality. There are about 200 described species, distributed in five genera: Euglossa
, Eulaema
, Eufriesea
, Exaerete
and the monotypic
Aglae
, all exclusively occurring in South or Central America (though one species, Euglossa viridissima, has become established in the United States
). The latter two genera are cleptoparasites in the nests of other orchid bees. All except Eulaema are characterized by brilliant metallic coloration, primarily green, gold, and blue.
Females gather pollen and nectar as food from a variety of plants, and resins, mud and other materials for nest building. Some of the same food plants are also used by the males, which leave the nest upon hatching and do not return.
s) throughout their lives, primarily from orchids in the subtribes Stanhopeinae
and Catasetinae
, where all species are exclusively pollinated by euglossine males. These orchids do not produce nectar, and hide the pollen on a single anther under an anther cap; they are not visited by females. The whole pollinarium becomes attached to the male as it leaves the flower. Several flowers from other plant families are also visited by the bees: Spathiphyllum
and Anthurium
(Araceae
), Drymonia
and Gloxinia
(Gesneriaceae
), Cyphomandra
(Solanaceae
), and Dalechampia
(Euphorbiaceae
) contain one or more species that attract male euglossines.
The chemicals are picked up using special brushes on the forelegs, transferred from there by rubbing the brushes against combs on the middle legs, and finally these combs are pressed into grooves on the dorsal edge of the hind legs, squeezing the chemicals past the waxy hairs which block the opening of the groove, and into a sponge-like cavity inside the hind tibia.
The accumulated "fragrances" are evidently released by the males at their display sites in the forest understory, where matings are known to take place. Although the accumulated volatiles have long been believed to serve as a signal to females, female attraction to male odors has never been demonstrated in behavioral experiments. The behavior of volatile collection is essentially unique in the animal kingdom. Single synthetic compounds are commonly used as bait to attract and collect males for study, and include many familiar flavorings and odors considered appealing to humans (e.g., methyl salicylate
, eugenol
, cineole, benzyl acetate
, methyl benzoate
, methyl cinnamate
), and others which are not (e.g., skatole
).
Neotropical orchids themselves often exhibit elaborate adaptations involving highly specific placement of pollen packets (pollinia
) on the bodies of the male orchid bees; the specificity of their placement ensures that cross-pollination
only occurs between orchids of the same species. Different orchid bee males are attracted to different chemicals, so there is also some specificity regarding which orchid bees visit which types of orchid. The early description of this pollination system was by Charles Darwin
, though at the time, he believed the bees were females. Not all orchids utilize euglossines as pollen vectors, of course; among the other types of insects exploited are other types of bees, wasps, flies, ants, and moths.
The male Eufriesea
purpurata is highly unusual in actively collecting the insecticide
DDT
in huge amounts from houses in Brazil
, without suffering any harm from it.
Pollen basket
The pollen basket or corbicula is part of the tibia on the hind legs of the four related lineages of apid bees that used to comprise the family Apidae: the honey bees, bumblebees, stingless bees, and orchid bees...
bees whose non-parasitic members do not all possess eusocial behavior
Eusociality
Eusociality is a term used for the highest level of social organization in a hierarchical classification....
. Most of the species are solitary, though a few are communal, or exhibit simple forms of eusociality. There are about 200 described species, distributed in five genera: Euglossa
Euglossa
Euglossa is a genus of orchid bees . Like all their close relatives, they are native to the Neotropics; an introduced population exists in Florida. They are typically bright metallic blue, green, coppery, or golden....
, Eulaema
Eulaema
Eulaema is a genus of large-bodied euglossine bees that occur primarily in the Neotropics.They are robust brown or black bees, hairy or velvety and often striped with yellow or orange, typically resembling bumblebees.-Distribution:...
, Eufriesea
Eufriesea
Eufriesea is a genus of euglossine bees. Like all orchid bees, they are restricted to the Neotropics.They are of metallic or brown/black color and hairy.-Distribution:...
, Exaerete
Exaerete
Exaerete is a genus of euglossine bees. Like all orchid bees, they are restricted to the Neotropics.Like most orchid bees, they are metallic , but they are cleptoparasites in the nests of other euglossines in the genera Eufriesea and Eulaema.-Species:* E. azteca Moure, 1964* E. dentata * E...
and the monotypic
Monotypic
In biology, a monotypic taxon is a taxonomic group with only one biological type. The term's usage differs slightly between botany and zoology. The term monotypic has a separate use in conservation biology, monotypic habitat, regarding species habitat conversion eliminating biodiversity and...
Aglae
Aglae
Aglae is a genus of euglossine bees, with the only described species Aglae caerulea. Like all orchid bees, it is restricted to the Neotropics.They are metallic blue....
, all exclusively occurring in South or Central America (though one species, Euglossa viridissima, has become established in the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
). The latter two genera are cleptoparasites in the nests of other orchid bees. All except Eulaema are characterized by brilliant metallic coloration, primarily green, gold, and blue.
Females gather pollen and nectar as food from a variety of plants, and resins, mud and other materials for nest building. Some of the same food plants are also used by the males, which leave the nest upon hatching and do not return.
Fragrance collection
Male orchid bees have uniquely modified legs which are used to collect and store different volatile compounds (often esterEster
Esters are chemical compounds derived by reacting an oxoacid with a hydroxyl compound such as an alcohol or phenol. Esters are usually derived from an inorganic acid or organic acid in which at least one -OH group is replaced by an -O-alkyl group, and most commonly from carboxylic acids and...
s) throughout their lives, primarily from orchids in the subtribes Stanhopeinae
Stanhopeinae
Stanhopeinae is a subtribe of plants in the Orchid family.The subtribe in the strict sense, have viscidia and stipes that are thin and strap-like, they are adapted for attachment to edge of the bee's scutellum or to a leg. Pseudobulbs are usually ribbed/four-angled or flattened. Leaves are...
and Catasetinae
Catasetinae
The Catasetinae is a subtribe within the Orchidaceae. Its members are widespread in lowland tropical Central and South America up to 1,500 meters. They are found on trees, stumps or old fence posts....
, where all species are exclusively pollinated by euglossine males. These orchids do not produce nectar, and hide the pollen on a single anther under an anther cap; they are not visited by females. The whole pollinarium becomes attached to the male as it leaves the flower. Several flowers from other plant families are also visited by the bees: Spathiphyllum
Spathiphyllum
Spathiphyllum is a genus of about 40 species of monocotyledonous flowering plants in the family Araceae, native to tropical regions of the Americas and southeastern Asia. Certain species of Spathiphyllum are commonly known as Spath or Peace Lilies.They are evergreen herbaceous perennial plants with...
and Anthurium
Anthurium
Anthurium , is a large genus of about 600–800 species, belonging to the arum family . Anthurium can also be called "Flamingo Flower" or "Boy Flower", both referring to the structure of the spathe and spadix....
(Araceae
Araceae
Araceae are a family of monocotyledonous flowering plants in which flowers are borne on a type of inflorescence called a spadix. The spadix is usually accompanied by, and sometimes partially enclosed in, a spathe or leaf-like bract. Also known as the Arum family, members are often colloquially...
), Drymonia
Drymonia
This article is about the moth genus Drymonia; for the plant genus Drymonia see Gesneriaceae.Drymonia is a genus of moths of the Notodontidae family...
and Gloxinia
Gloxinia
Gloxinia can refer to:*The genus Gloxinia of flowering plants in the family Gesneriaceae*The plant species Sinningia speciosa, formerly classified in the genus Gloxinia and still commonly known by that name, in the family Gesneriaceae...
(Gesneriaceae
Gesneriaceae
Gesneriaceae is a family of flowering plants consisting of ca. 150 genera and ca. 3,200 species in the Old World and New World tropics and subtropics, with a very small number extending to temperate areas. Many species have colorful and showy flowers and are cultivated as ornamental plants.Most...
), Cyphomandra
Cyphomandra
Cyphomandra was a genus in the flowering plant family Solanaceae . It used to contain about 35 species native to countries of the Americas from Mexico southwards to Northern Argentina....
(Solanaceae
Solanaceae
Solanaceae are a family of flowering plants that include a number of important agricultural crops as well as many toxic plants. The name of the family comes from the Latin Solanum "the nightshade plant", but the further etymology of that word is unclear...
), and Dalechampia
Dalechampia
Dalechampia is a genus of plant of the family Euphorbiaceae and of the monogeneric subtribe Dalechampiinae. It comprises about 120 species, all found in lowland tropical areas and especially in the Americas. There are ca. 90 species in the Americas and ca. 10 species each, in Africa, Madagascar,...
(Euphorbiaceae
Euphorbiaceae
Euphorbiaceae, the Spurge family are a large family of flowering plants with 300 genera and around 7,500 species. Most are herbs, but some, especially in the tropics, are also shrubs or trees. Some are succulent and resemble cacti....
) contain one or more species that attract male euglossines.
The chemicals are picked up using special brushes on the forelegs, transferred from there by rubbing the brushes against combs on the middle legs, and finally these combs are pressed into grooves on the dorsal edge of the hind legs, squeezing the chemicals past the waxy hairs which block the opening of the groove, and into a sponge-like cavity inside the hind tibia.
The accumulated "fragrances" are evidently released by the males at their display sites in the forest understory, where matings are known to take place. Although the accumulated volatiles have long been believed to serve as a signal to females, female attraction to male odors has never been demonstrated in behavioral experiments. The behavior of volatile collection is essentially unique in the animal kingdom. Single synthetic compounds are commonly used as bait to attract and collect males for study, and include many familiar flavorings and odors considered appealing to humans (e.g., methyl salicylate
Methyl salicylate
Methyl salicylate is a natural product of many species of plants. Some of the plants which produce it are called wintergreens, hence the common name.-Botanical background:...
, eugenol
Eugenol
Eugenol is a phenylpropene, an allyl chain-substituted guaiacol. Eugenol is a member of the phenylpropanoids class of chemical compounds. It is a clear to pale yellow oily liquid extracted from certain essential oils especially from clove oil, nutmeg, cinnamon, basil and bay leaf. It is slightly...
, cineole, benzyl acetate
Benzyl acetate
Benzyl acetate is an organic compound with the molecular formula C9H10O2. It is the ester formed by condensation of benzyl alcohol and acetic acid....
, methyl benzoate
Methyl benzoate
Methyl benzoate is an ester with the chemical formula C6H5COOCH3. It is formed by the condensation of methanol and benzoic acid, in presence of a strong acid such as hydrochloric acid. It is a colorless liquid that is poorly soluble in water, but miscible with organic solvents.-Reactions:Methyl...
, methyl cinnamate
Methyl cinnamate
Methyl cinnamate is the methyl ester of cinnamic acid and is a white or transparent solid with a strong, aromatic odor. It is found naturally in a variety of plants, including in fruits, like strawberry, and some culinary spices, such as Sichuan pepper and some varieties of basil...
), and others which are not (e.g., skatole
Skatole
Skatole or 3-methylindole is a mildly toxic white crystalline organic compound belonging to the indole family. It occurs naturally in feces and coal tar, and has a strong fecal odor...
).
Neotropical orchids themselves often exhibit elaborate adaptations involving highly specific placement of pollen packets (pollinia
Pollinium
Pollinium, or plural pollinia, is a coherent mass of pollen grains in a plant.They are the product of only one anther, but are transferred, during pollination, as a single unit. This is regularly seen in plants such as orchids and many species of milkweeds .Most orchids have waxy pollinia...
) on the bodies of the male orchid bees; the specificity of their placement ensures that cross-pollination
Pollination
Pollination is the process by which pollen is transferred in plants, thereby enabling fertilisation and sexual reproduction. Pollen grains transport the male gametes to where the female gamete are contained within the carpel; in gymnosperms the pollen is directly applied to the ovule itself...
only occurs between orchids of the same species. Different orchid bee males are attracted to different chemicals, so there is also some specificity regarding which orchid bees visit which types of orchid. The early description of this pollination system was by Charles Darwin
Charles Darwin
Charles Robert Darwin FRS was an English naturalist. He established that all species of life have descended over time from common ancestry, and proposed the scientific theory that this branching pattern of evolution resulted from a process that he called natural selection.He published his theory...
, though at the time, he believed the bees were females. Not all orchids utilize euglossines as pollen vectors, of course; among the other types of insects exploited are other types of bees, wasps, flies, ants, and moths.
The male Eufriesea
Eufriesea
Eufriesea is a genus of euglossine bees. Like all orchid bees, they are restricted to the Neotropics.They are of metallic or brown/black color and hairy.-Distribution:...
purpurata is highly unusual in actively collecting the insecticide
Insecticide
An insecticide is a pesticide used against insects. They include ovicides and larvicides used against the eggs and larvae of insects respectively. Insecticides are used in agriculture, medicine, industry and the household. The use of insecticides is believed to be one of the major factors behind...
DDT
DDT
DDT is one of the most well-known synthetic insecticides. It is a chemical with a long, unique, and controversial history....
in huge amounts from houses in Brazil
Brazil
Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...
, without suffering any harm from it.