Squash bee
Encyclopedia
The name Squash bee is applied to two related genera of bee
s in the tribe Eucerini
; Peponapis and Xenoglossa. Both genera are oligoleges (pollen specialists) on the plant genus Cucurbita
and closely related plants (squash, cucumbers, etc.). They are small genera, containing only 13 and 7 described species, respectively, and their combined range is nearly identical to the range of Cucurbita in the New World, from South America
to North America
. Their range has become somewhat expanded along with the movement of cucurbits into other areas (as crop plants). The bees themselves are of moderate size, equal to various bumblebee
s. The pollen-carrying hairs on their legs (the scopa
) are unbranched or nearly so, and sparse, to accommodate the exceptionally large, coarse pollen of the host plants. They have also evolved a matinal daily activity cycle, flying before sunrise. Some Xenoglossa species have become morphologically specialized to fly while it is still dark, with greatly enlarged ocelli to allow them to fly in near-darkness.
The two genera are sometimes thought to be sister taxa, but there are enough differences between them to suggest that the similarities may be due to convergent evolution
, based on their adaptation to utilize the same host plants
Studies have been carried out to compare Peponapis and honey bees regarding their effectiveness in pollinating cucurbits. The findings point to the squash bees being more effective and suggest that the current practice of renting colonies of honey bees to perform this task may be unnecessary .
Bee
Bees are flying insects closely related to wasps and ants, and are known for their role in pollination and for producing honey and beeswax. Bees are a monophyletic lineage within the superfamily Apoidea, presently classified by the unranked taxon name Anthophila...
s in the tribe Eucerini
Eucerini
The Eucerini is the most diverse tribe in the family Apidae, with over 32 genera worldwide that were previously classified as members of the family Anthophoridae. All species are solitary, though many nest in large aggregations, and it is also occasionally possible to find large "sleeping"...
; Peponapis and Xenoglossa. Both genera are oligoleges (pollen specialists) on the plant genus Cucurbita
Cucurbita
Cucurbita is a genus in the gourd family Cucurbitaceae first cultivated in Mesoamerica and now used in many parts of the world. It includes species grown for their fruit and edible seeds , as well as some species grown only as gourds...
and closely related plants (squash, cucumbers, etc.). They are small genera, containing only 13 and 7 described species, respectively, and their combined range is nearly identical to the range of Cucurbita in the New World, from South America
South America
South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...
to North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
. Their range has become somewhat expanded along with the movement of cucurbits into other areas (as crop plants). The bees themselves are of moderate size, equal to various bumblebee
Bumblebee
A bumble bee is any member of the bee genus Bombus, in the family Apidae. There are over 250 known species, existing primarily in the Northern Hemisphere although they are common in New Zealand and in the Australian state of Tasmania.Bumble bees are social insects that are characterised by black...
s. The pollen-carrying hairs on their legs (the scopa
Scopa (biology)
The term scopa is used to refer to any of a number of different modifications on the body of a non-parasitic bee that form a pollen-carrying apparatus. In most bees, the scopa is simply a particularly dense mass of elongated, often branched, hairs on the hind leg...
) are unbranched or nearly so, and sparse, to accommodate the exceptionally large, coarse pollen of the host plants. They have also evolved a matinal daily activity cycle, flying before sunrise. Some Xenoglossa species have become morphologically specialized to fly while it is still dark, with greatly enlarged ocelli to allow them to fly in near-darkness.
The two genera are sometimes thought to be sister taxa, but there are enough differences between them to suggest that the similarities may be due to convergent evolution
Convergent evolution
Convergent evolution describes the acquisition of the same biological trait in unrelated lineages.The wing is a classic example of convergent evolution in action. Although their last common ancestor did not have wings, both birds and bats do, and are capable of powered flight. The wings are...
, based on their adaptation to utilize the same host plants
Studies have been carried out to compare Peponapis and honey bees regarding their effectiveness in pollinating cucurbits. The findings point to the squash bees being more effective and suggest that the current practice of renting colonies of honey bees to perform this task may be unnecessary .