''Anochetus dubius'' 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. dubius'' 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 dubius'' is known from the solitary fossil insect which, along with two soil particles, is an

inclusion Inclusion or Include may refer to: Sociology * Social inclusion, aims to create an environment that supports equal opportunity for individuals and groups that form a society. ** Inclusion (disability rights), promotion of people with disabilitie ...

in a transparent yellow chunk 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 specimen was collected from an undetermined amber mine in 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 of 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 as the 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, number "Do-4192", was preserved 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 in

Baden-Württemberg Baden-Württemberg (; ), commonly shortened to BW or BaWü, is a German state () in Southwest Germany, east of the Rhine, which forms the southern part of Germany's western border with France. With more than 11.07 million inhabitants across a ...

Germany Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, and the most populous member state of the European Union. Germany is situated betwe ...

. The holotype fossil was first studied by entomologist Maria L. De Andrade of the University of Basle with her 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 ''Stuttgarter Beiträge zur Naturkunde. Serie B (Geologie und Paläontologie)''. 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 ...

''dubius'' is derived from the

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 ...

''dubius'' meaning "doubtful", a reference to the uncertain affinities to any specific modern ''Anochetus'' species group. The species is one of eight ''Anochetus'' which have been described from Dominican amber. Two species were described prior to ''A. dubius'': '' A. corayi'' in 1980 and '' A. brevidentatus'' in 1991. The remaining five species—'' A. ambiguus'', '' A. conisquamis'', '' A. exstinctus'', '' A. intermedius'', and '' A. lucidus''—were all described by De Andrade in the same 1994 paper as ''A. dubius''. A number of modern species live in the Greater Antilles, with at least three modern species found on Hispaniola.

Description

The ''Anochetus dubius''

type specimen In biology, a type is a particular wiktionary:en:specimen, specimen (or in some cases a group of specimens) of an organism to which the scientific name of that organism is formally attached. In other words, a type is an example that serves to a ...

is well preserved, though it is missing some body structures such as both hind tarsi and tibiae, and the entire specimen is surrounded by a brownish bacterial growth. The specimen has an estimated body length of , with a head and mandibles. The overall coloration of the body is a brown darkening on the head ad gaster, with the coxae and portions of the

trochanters A trochanter is a Tubercle (human skeleton), tubercle of the femur near its joint with the hip bone. In humans and most mammals, the trochanters serve as important muscle attachment sites. Humans are known to have three trochanters, though the ...

and femora being a reddish tone. The mandibles are just under the width of the head and about one-quarter the length, flare in width from the base to tips, and have between them ten teeth which decrease in size from the tips to the bases. The apical three teeth on each mandible blade are elongated and slender for grasping prey, with the apical two teeth longer than the third tooth. Both the mesonotum and pronotum have a slight "U"-shaped profile, with the undersides of each curved upwards. The propodium sports short spines, long, on the rear edge, while the petiole has two longer spines, long, placed near the center of the petiolar node.

References

{{Taxonbar, from=Q3687438 †Anochetus dubius 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 1994