''Acanthognathus poinari'' is an extinct

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 ...

ant Ants are eusocial insects of the family Formicidae and, along with the related wasps and bees, belong to the order Hymenoptera. Ants evolved from vespoid wasp ancestors in the Cretaceous period. More than 13,800 of an estimated total of ...

in the subfamily Myrmicinae known from a single possibly

Miocene The Miocene ( ) is the first epoch (geology), 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 mea ...

fossil found on Hispaniola. ''A. poinari'' is the first species of the ant genus ''

Acanthognathus ''Acanthognathus'' is a genus of ants that are found in tropical Central and South America.Brown, W. L., Jr., & W. W. Kempf (1969). ''A Revision of the Neotropical Dacetine Ant Genus Acanthognathus (Hymenoptera: Formicidae.'' Psyche 76(2): 87-10 ...

'' 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 inc ...

and is one of several species of ''Acanthognathus'' found in the Greater Antillas.

History and classification

''Acanthognathus poinari'' is known from a solitary fossil insect which, along with six dipteran and a leaf section, 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 disabiliti ...

in a transparent chunk of

. The amber was produced by the extinct '' Hymenaea protera'', which formerly grew on Hispaniola, 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 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 (Haiti), Tortuga island in Haiti, and to the southeast through lowlands to where it rises ...

mountains, 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 with ...

. The amber dates from at least the

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

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 for catching food and other uses; and commonly ...

and may be as old as the Middle Eocene, based on the associated fossil

coccoliths Coccoliths are individual plates or scales of calcium carbonate formed by coccolithophores (single-celled phytoplankton such as '' Emiliania huxleyi'') and cover the cell surface arranged in the form of a spherical shell, called a ''coccosphere'' ...

. 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 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 sever ...

amber specimen, number H-10-135, is currently preserved in the amber collections of noted amber researcher George Poinar Jr., which at the time of description were housed in the

University of California, Berkeley The University of California, Berkeley (UC Berkeley, Berkeley, Cal, or California) is a public land-grant research university in Berkeley, California. Established in 1868 as the University of California, it is the state's first land-grant u ...

. The fossil was first studied by entomologists Cesare Baroni Urbani and Maria L. De Andrade of the

University of Basle The University of Basel (Latin: ''Universitas Basiliensis'', German: ''Universität Basel'') is a university in Basel, Switzerland. Founded on 4 April 1460, it is Switzerland's oldest university and among the world's oldest surviving universitie ...

with their 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 ''Transactions of the American Entomological Society''. The specific epithet ''poinari'' is a patronym honoring George Poinar for his enthusiasm for amber which interested the authors into study of the specimens. Prior to the species formal description in 1994 the known distribution of the genus was confined to tropical Central and South America, ranging from Honduras south to Northern

Argentina Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the second-largest country in South America after Brazil, th ...

and Southeastern

Brazil Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...

. Member species are active predators which use highly enlarged and modified trap-jaw mandibles. Acanthognathus teledectus casent0039799 head 1

Acanthognathus teledectus casent0039799 head 1

Description

The ''Acanthognathus poinari'' specimen is well preserved with an estimated body length of , including the enlarged mandibles. The overall coloration of ''A. poinari'' is a glossy reddish brown in general, which slightly lightens on the legs and antennae. The antennae are a distinct club shape with 2 joints. The mandibles and scape are slightly shorter than the head in combined length an host a number of sparse hairs. The gaster and petiole are smooth to very faintly punctate or striate, with the stria getting more distinct on the trunk. The head capsule shows distinct strong reticulation and patterning. ''A. poinari'' is separated from the living genera by the distinct transverse ornamentation found on the posterior cephalic angles.

References

{{Taxonbar, from=Q14446732 Miocene insects of North America Fossil taxa described in 1994 Fauna of Hispaniola Myrmicinae Insects of the Dominican Republic Extinct animals of the Dominican Republic Fossil ant taxa Prehistoric insects of the Caribbean Fossils of the Dominican Republic Dominican amber