''Odontomachus spinifer'' 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 one 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 ...

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 ...

. ''O. spinifer'' is one of two species in the ant genus '' Odontomachus'' 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 ''Odontomachus'' species found in the

Greater Antilles The Greater Antilles ( es, Grandes Antillas or Antillas Mayores; french: Grandes Antilles; ht, Gwo Zantiy; jam, Grieta hAntiliiz) is a grouping of the larger islands in the Caribbean Sea, including Cuba, Hispaniola, Puerto Rico, Jamaica, and ...

History and classification

''Odontomachus spinifer'' is known from a solitary fossil insect which, along with a microhymenopteran, 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-2215", 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 1994

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 ...

''spinifer'' 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 ...

word which means "bearing a spine", a reference to the large projection on the top of the petiole. Odontomachus spinifer SMNSDO2215 head

Based on the head structure, ''O. spinifer'' was suggested to be part of the ''O. haematodus'' species group, closely placed with the species '' O. affinis'', '' O. mayi'', and '' O. panamensis''. The three modern species are from Brazil and Guyana up through Panama and Costa Rica. The two modern species found on the island of Hispaniola, '' O. bauri'' and '' O. insularis'' are not closely placed to ''O. spinifer'', having different structuring of the heads upper surface. When first described, ''O. spinifer'' was one of two ''Odontomachus'' species that had been described from fossils. It and '' Odontomachus pseudobauri'' were both described by De Andrade from Dominican amber in the same paper. A third species ''

Odontomachus paleomyagra ''Odontomachus paleomyagra'' is an extinct species of formicid in the ant subfamily Ponerinae known from a Miocene fossil found in Europe. History and classification ''O. paleomyagra'' is known from a single ant found in the Czech Republic.Wap ...

'', the first compression fossil species, was described in 2014 from a worker found in

Priabonian The Priabonian is, in the ICS's geologic timescale, the latest age or the upper stage of the Eocene Epoch or Series. It spans the time between . The Priabonian is preceded by the Bartonian and is followed by the Rupelian, the lowest stage of t ...

age

lignite Lignite, often referred to as brown coal, is a soft, brown, combustible, sedimentary rock formed from naturally compressed peat. It has a carbon content around 25–35%, and is considered the lowest rank of coal due to its relatively low heat ...

deposits of the Most Basin,

Czech Republic The Czech Republic, or simply Czechia, is a landlocked country in Central Europe. Historically known as Bohemia, it is bordered by Austria to the south, Germany to the west, Poland to the northeast, and Slovakia to the southeast. The ...

Description

The ''O. spinifer'' worker is approximately in length, and has a shining exoskeleton of yellowish red to reddish brown tones. The smooth exoskeleton has tiny punctuation found across the top of the head, mandibles, petiole node and the gaster. In contrast the frons, antennae depressions, pronotum, mesonotum and underside of the petiole are distinguished by varying degrees of striation. The head is large with a rectangular outline, being 2/3 longer than wide, with the rear margin of the head wider than the maximum width of the pronotum. The mandibles are almost as long as the head is wide and the chewing margin has twelve teeth increasing in size towards the tip, while the apex of each has three teeth, a preapical, intercalary, and an apical tooth. The antennae have notably long scapes that extend past the rear margin of the head capsule and curve slightly along their length. The first funicular segments of the antennae are double the length of the second segment and longer than any of the other 10 segments. The mesonotum and

propodeum The propodeum or propodium is the first abdominal segment in Apocrita Hymenoptera (wasps, bees and ants). It is fused with the thorax to form the mesosoma. It is a single large sclerite, not subdivided, and bears a pair of spiracles. It is strongl ...

have an elongated slender profile, as does the petiole, while the gaster is bell shaped along the connection with the petiole and the sting is partially retracted. There is a notably large backward curving spine formed from the upper surface of the petiole, being longer than the width of the petiole.

References

External links

* {{Taxonbar, from=Q14444356 †Odontomachus spinifer 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 1994