Ctenoplectrini
Encyclopedia
The bee tribe
Ctenoplectrini, with two genera, comprises nine species in tropical Africa
, ten in Asia
and one in Australia
. Most of them collect floral oil, pollen, and nectar from a few genera of Cucurbitaceae
, but three species are thought to be kleptoparasites. The Ctenoplectrini are characterised by short tongues, modified scopa
and large comb-like tibial spurs adapted to collect and carry a mixture of floral oils and pollen. The unusual morphology has made it difficult to infer their closest relatives, in turn preventing an understanding of these bees’ geographic and temporal origin and had led early authors to place them in their own family Ctenoplectridae. Recent molecular phylogenetic analyses find Ctenoplectrini to be monophyletic and closest to the Long-horned bees, Eucerini. The presumably cleptoparasitic species form a clade
(Ctenoplectrina) that is sister to the remaining species (Ctenoplectra), confirming the independent evolution
of kleptoparasitism
in this tribe
. Tree topology and molecular dating together suggest that Ctenoplectrini originated in Africa
in the Early Eocene
and that Ctenoplectra dispersed twice from Africa
to Asia
, sometime in the Late Eocene
, 30–40 million years ago, from where one species reached the Australian continent via Indonesia
and New Guinea
in the mid-Miocene
, c. 13 million years ago. Dry and cool mid-Miocene
climates also coincide with the divergence between Ctenoplectra bequaerti from West Africa
and Ctenoplectra terminalis from East and South Africa
, perhaps related to fragmentation of the equatorial African rainforest
belt. Nests are known from few species only, which use existing small holes in wood and stone or old nests of other bees, which they provision with a mixture of pollen and floral oil, exclusively gathered from plants of a few genera of the family Cucurbitaceae
.
Tribe
A tribe, viewed historically or developmentally, consists of a social group existing before the development of, or outside of, states.Many anthropologists use the term tribal society to refer to societies organized largely on the basis of kinship, especially corporate descent groups .Some theorists...
Ctenoplectrini, with two genera, comprises nine species in tropical Africa
Africa
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
, ten in Asia
Asia
Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...
and one in Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
. Most of them collect floral oil, pollen, and nectar from a few genera of Cucurbitaceae
Cucurbitaceae
The plant family Cucurbitaceae consists of various squashes, melons, and gourds, including crops such as cucumber, pumpkins, luffas, and watermelons...
, but three species are thought to be kleptoparasites. The Ctenoplectrini are characterised by short tongues, modified 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...
and large comb-like tibial spurs adapted to collect and carry a mixture of floral oils and pollen. The unusual morphology has made it difficult to infer their closest relatives, in turn preventing an understanding of these bees’ geographic and temporal origin and had led early authors to place them in their own family Ctenoplectridae. Recent molecular phylogenetic analyses find Ctenoplectrini to be monophyletic and closest to the Long-horned bees, Eucerini. The presumably cleptoparasitic species form a clade
Clade
A clade is a group consisting of a species and all its descendants. In the terms of biological systematics, a clade is a single "branch" on the "tree of life". The idea that such a "natural group" of organisms should be grouped together and given a taxonomic name is central to biological...
(Ctenoplectrina) that is sister to the remaining species (Ctenoplectra), confirming the independent evolution
Evolution
Evolution is any change across successive generations in the heritable characteristics of biological populations. Evolutionary processes give rise to diversity at every level of biological organisation, including species, individual organisms and molecules such as DNA and proteins.Life on Earth...
of kleptoparasitism
Kleptoparasitism
Kleptoparasitism or cleptoparasitism is a form of feeding in which one animal takes prey or other food from another that has caught, collected, or otherwise prepared the food, including stored food...
in this tribe
Tribe
A tribe, viewed historically or developmentally, consists of a social group existing before the development of, or outside of, states.Many anthropologists use the term tribal society to refer to societies organized largely on the basis of kinship, especially corporate descent groups .Some theorists...
. Tree topology and molecular dating together suggest that Ctenoplectrini originated in Africa
Africa
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
in the Early Eocene
Eocene
The Eocene Epoch, lasting from about 56 to 34 million years ago , is a major division of the geologic timescale and the second epoch of the Paleogene Period in the Cenozoic Era. The Eocene spans the time from the end of the Palaeocene Epoch to the beginning of the Oligocene Epoch. The start of the...
and that Ctenoplectra dispersed twice from Africa
Africa
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
to Asia
Asia
Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...
, sometime in the Late Eocene
Eocene
The Eocene Epoch, lasting from about 56 to 34 million years ago , is a major division of the geologic timescale and the second epoch of the Paleogene Period in the Cenozoic Era. The Eocene spans the time from the end of the Palaeocene Epoch to the beginning of the Oligocene Epoch. The start of the...
, 30–40 million years ago, from where one species reached the Australian continent via Indonesia
Indonesia
Indonesia , officially the Republic of Indonesia , is a country in Southeast Asia and Oceania. Indonesia is an archipelago comprising approximately 13,000 islands. It has 33 provinces with over 238 million people, and is the world's fourth most populous country. Indonesia is a republic, with an...
and New Guinea
New Guinea
New Guinea is the world's second largest island, after Greenland, covering a land area of 786,000 km2. Located in the southwest Pacific Ocean, it lies geographically to the east of the Malay Archipelago, with which it is sometimes included as part of a greater Indo-Australian Archipelago...
in the mid-Miocene
Miocene
The Miocene is a geological epoch of the Neogene Period and extends from about . The Miocene was named by Sir Charles Lyell. Its name comes from the Greek words and and means "less recent" because it has 18% fewer modern sea invertebrates than the Pliocene. The Miocene follows the Oligocene...
, c. 13 million years ago. Dry and cool mid-Miocene
Miocene
The Miocene is a geological epoch of the Neogene Period and extends from about . The Miocene was named by Sir Charles Lyell. Its name comes from the Greek words and and means "less recent" because it has 18% fewer modern sea invertebrates than the Pliocene. The Miocene follows the Oligocene...
climates also coincide with the divergence between Ctenoplectra bequaerti from West Africa
Africa
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
and Ctenoplectra terminalis from East and South Africa
Africa
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
, perhaps related to fragmentation of the equatorial African rainforest
Rainforest
Rainforests are forests characterized by high rainfall, with definitions based on a minimum normal annual rainfall of 1750-2000 mm...
belt. Nests are known from few species only, which use existing small holes in wood and stone or old nests of other bees, which they provision with a mixture of pollen and floral oil, exclusively gathered from plants of a few genera of the family Cucurbitaceae
Cucurbitaceae
The plant family Cucurbitaceae consists of various squashes, melons, and gourds, including crops such as cucumber, pumpkins, luffas, and watermelons...
.