''Apterostigma electropilosum'' is an

extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...

species of ant in the subfamily

Myrmicinae Myrmicinae is a subfamily of ants, with about 140 extant genera; their distribution is cosmopolitan. The pupae lack cocoons. Some species retain a functional sting. The petioles of Myrmicinae consist of two nodes. The nests are permanent and ...

known from a single possibly Miocene fossil found on

Hispaniola Hispaniola (, also ; es, La Española; Latin and french: Hispaniola; ht, Ispayola; tnq, Ayiti or Quisqueya) is an island in the Caribbean that is part of the Greater Antilles. Hispaniola is the most populous island in the West Indies, and th ...

. ''A. electropilosum'' is one of only two species of the ant genus '' Apterostigma'' and one of five attini species to have been described from fossils found in Dominican amber.

History and classification

''Apterostigma electropilosum'' is known from a solitary fossil insect which is an inclusion in a transparent chunk of Dominican amber. The amber was produced by the extinct ''

Hymenaea protera ''Hymenaea protera'' is an extinct prehistoric leguminous tree, the probable ancestor of present-day ''Hymenaea'' species. Most neotropical ambers come from its fossilized resin, including the famous Dominican amber. ''H. protera'' once grew in ...

'', which formerly grew on

, across northern South America and up to southern Mexico. The specimens were collected from an undetermined amber mine in fossil bearing rocks of the Cordillera Septentrional mountains, northern Dominican Republic. The amber dates from at least the Burdigalian stage of the Miocene, based on studying the associated fossil foraminifera and may be as old as the Middle Eocene, based on the associated fossil coccoliths. This age range is due to the host rock being secondary deposits for the amber, and the Miocene the age range is only the youngest that it might be. The holotype amber specimen, number DR-14-984, is currently preserved in the amber collections of the US National Museum, and is labeled as part of the Smithsonian Institution ant database as number 00443127. The fossil was first studied by entomologist Ted R. Schultz of the National Museum of Natural History with his 2007

type description A species description is a formal description of a newly discovered species, usually in the form of a scientific paper. Its purpose is to give a clear description of a new species of organism and explain how it differs from species that have ...

of the new species being published in the journal ''Memoirs of the American Entomological Institute''. The

specific epithet In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...

''electropilosum'' is a combination of the Latin ''electrum'' meaning "amber" and pilosum, the ''Apterostigma'' species group which ''A. electropilosum'' it part of. Prior to the species formal description in 2007, no ''Apterostigma'' species were known from the fossil record, however three other Attini species were already known from Dominican Amber, ''

Trachymyrmex primaevus ''Trachymyrmex '' is a genus of fungus-growing ants in the subfamily Myrmicinae. The genus is mainly tropical in distribution, with most species being found in Central and South America. The queens of the species appear to mate with only one ...

'', ''

Cyphomyrmex maya ''Cyphomyrmex'' is a genus of fungus-growing ants found primarily in South and Central America. However, some species do come up to the southern portion of North America. They grow a variety of fungi in the tribe Leucocoprineae. Most fungal garde ...

'', and ''

Cyphomyrmex taino ''Cyphomyrmex'' is a genus of fungus-growing ants found primarily in South and Central America. However, some species do come up to the southern portion of North America. They grow a variety of fungi in the tribe Leucocoprineae. Most fungal garde ...

''. Schultz's paper described a second Dominican amber ''Apterostigma'' species, '' A. eowilsoni''. Bringing the total Attini fossil record to five species. Apterostigma pilosum casent0603533 profile 1

Apterostigma pilosum casent0603533 profile 1

Description

The ''Apterostigma electropilosum'' specimen is well preserved with an estimated Weber's length of and a head length of . The overall coloration of the species is hard to determine due to a sporadic microscopic coating of fine bubbles, possibly of oil or other liquid from punctures in the integument after entombment by the resin. The body has a fine covering of simple upright setae which reach a total length of . The head capsule shows a clypeus which is smooth and shiny, a feature seen in the living ''pilosum'' group of ''Apterostigma'' species. The occiput, rear area of the head capsule, is elongated to a slight neck with a smooth integument surface. The antennae are composed of eleven segments, in which the tip segment is 2.5 times the length of the next segment. The eyes are rounded and bulbous in structure with a circumference of ten ommatidia. While the clypeus structure places ''A. electropilosum'' in the ''pilosum'' group, the combination of rounded frontal head capsule lobes, mandibles with eleven teeth, and the angle of clypeus border is not seen in any

extant Extant is the opposite of the word extinct. It may refer to: * Extant hereditary titles * Extant literature, surviving literature, such as ''Beowulf'', the oldest extant manuscript written in English * Extant taxon, a taxon which is not extinct, ...

species.

References

{{Taxonbar, from=Q18209484 Myrmicinae Fossil ant taxa Burdigalian life Neogene Dominican Republic Miocene insects of North America Prehistoric insects of the Caribbean Fauna of Hispaniola Insects of the Dominican Republic Fossils of the Dominican Republic Dominican amber Fossil taxa described in 2007