''Anochetus brevidentatus'' 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 In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

of ant in the subfamily Ponerinae known from two possibly

Miocene The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recen ...

fossils 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. ambiguus'' is one of eight species in the ant genus ''

Anochetus ''Anochetus'' is a genus of small, carnivorous ants found in the tropics and subtropics throughout the world. This genus is present in both the Old and New World and is certainly native to all continents except Antarctica and Europe. In Europe o ...

'' to have been described from fossils found in

Dominican amber Dominican amber is amber from the Dominican Republic derived from resin of the extinct tree ''Hymenaea protera''. Dominican amber differentiates itself from Baltic amber by being nearly always transparent, and it has a higher number of fossil incl ...

and is one of a number of ''Anochetus'' species found in the Greater Antillies.

History and classification

''Anochetus brevidentatus'' is known from two solitary fossil insects which are inclusions in transparent chunks of

. 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 type specimen was collected from the La Toca Mine near las Aguitas, while the second specimen is from an undetermined amber mine. Both are from fossil bearing rocks of the

Cordillera Septentrional The Cordillera Septentrional is a mountain range that runs parallel to the north coast of the Dominican Republic, with extensions to the northwest as Tortuga island in Haiti, and to the southeast through lowlands to where it rises as the Sierra d ...

mountains in the northern

Dominican Republic The Dominican Republic ( ; es, República Dominicana, ) is a country located on the island of Hispaniola in the Greater Antilles archipelago of the Caribbean region. It occupies the eastern five-eighths of the island, which it shares wit ...

. The amber dates from at least the

Burdigalian The Burdigalian is, in the geologic timescale, an age (geology), age or stage (stratigraphy), stage in the early Miocene. It spans the time between 20.43 ± 0.05 annum, Ma and 15.97 ± 0.05 Ma (million years ago). Preceded by the Aquitanian (sta ...

stage of the Miocene, based on studying the associated fossil

foraminifera Foraminifera (; Latin for "hole bearers"; informally called "forams") are single-celled organisms, members of a phylum or class of amoeboid protists characterized by streaming granular Ectoplasm (cell biology), ectoplasm for catching food and ot ...

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 age range is only the youngest that it might be. At the time of description, the

holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of several ...

specimen was preserved in the Museum of Comparative Zoology at

Harvard University Harvard University is a private Ivy League research university in Cambridge, Massachusetts. Founded in 1636 as Harvard College and named for its first benefactor, the Puritan clergyman John Harvard, it is the oldest institution of higher le ...

. The holotype fossil was first studied by entomologist William MacKay with his 1991

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 be ...

of the new species being published in the ''Journal of the New York Entomological Society''. 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 ...

''brevidentatus'' is derived

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...

as a reference to the short length of the spines on the petiole. The second known specimen was identified by entomologist Maria L. De Andrade of the University of Basle from a specimen in the

State Museum of Natural History Stuttgart The State Museum of Natural History Stuttgart (german: Staatliches Museum für Naturkunde Stuttgart), abbreviated SMNS, is one of the two state of Baden-Württemberg's natural history museums. Together with the State Museum of Natural History ...

amber collections and briefly described in 1994. ''A. brevidentatus'' is one of eight ''Anochetus'' species which have been described from Dominican amber. One species, '' A. corayi'', was published earlier than ''A. brevidentatus'', being described in 1980. The remaining six species; '' A. ambiguus'', '' A. conisquamis'', '' A. dubius'', '' A. exstinctus'', '' A. intermedius'', and '' A. lucidus'' were all described by De Andrade in the same 1994 paper. A number of modern species live in the Greater Antilles, with at least three modern species found on Hispaniola.

Description

The ''Anochetus ambiguus'' type specimen is well preserved, though it shows some distortion from the amber moving after entombment and is missing some body structures. The second specimen has an estimated body length of . The

mesosoma The mesosoma is the middle part of the body, or tagma, of arthropods whose body is composed of three parts, the other two being the prosoma and the metasoma. It bears the legs, and, in the case of winged insects, the wings. In hymenopterans of t ...

has distinct fine striae covering most of its surface and the gaster is smooth and shiny. The upper side of the head, mandibles, pronotum, and gaster sport sparse erect hairs. The mandibles have a flare in width near the center of their length and sport between 9 and 10 teeth with the apical three teeth on each mandible blade elongated and slender for grasping prey. The propodium sports short spines on the rear edge, while the petiole two spines which angle vertically up from the petiole face.

References

{{Taxonbar, from=Q3687401 †Anochetus brevidentatus Fossil ant taxa Burdigalian life 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 1991