''Acanthostichus hispaniolicus'' is an

extinct Extinction is the termination of an organism by the death of its Endling, last member. A taxon may become Functional extinction, functionally extinct before the death of its last member if it loses the capacity to Reproduction, reproduce and ...

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

ant Ants are Eusociality, eusocial insects of the Family (biology), family Formicidae and, along with the related wasps and bees, belong to the Taxonomy (biology), order Hymenoptera. Ants evolved from Vespoidea, vespoid wasp ancestors in the Cre ...

in the subfamily

Dorylinae Dorylinae is an ant subfamily, with distributions in both the Old World and New World. Brady ''et al.'' (2014) Synonym (taxonomy), synonymized the previous dorylomorph subfamilies (Aenictinae, Aenictogitoninae, Cerapachyinae, Ecitoninae, and Lep ...

known from a group of 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 ...

fossils found on the

Caribbean The Caribbean ( , ; ; ; ) is a region in the middle of the Americas centered around the Caribbean Sea in the Atlantic Ocean, North Atlantic Ocean, mostly overlapping with the West Indies. Bordered by North America to the north, Central America ...

island of

Hispaniola Hispaniola (, also ) is an island between Geography of Cuba, Cuba and Geography of Puerto Rico, Puerto Rico in the Greater Antilles of the Caribbean. Hispaniola is the most populous island in the West Indies, and the second-largest by List of C ...

. ''A. hispaniolicus'' is the first species of the ant genus '' Acanthostichus'' 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 in ...

, and is the only species of ''Acanthostichus'' found in the West Indies.

History and classification

''Acanthostichus hispaniolicus'' is known from four fossils insects which are inclusions in a single, transparent chunk of

. The amber was produced by the extinct '' Hymenaea protera'', which formerly grew on

, across northern South America and up to southern Mexico. The amber specimens, numbers Do-5205-1, Do-5205-2, Do-5205-3, and Do-5205-4; which entomb the

holotype A holotype (Latin: ''holotypus'') is a single physical example (or illustration) of an organism used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of s ...

and three

paratype In zoology and botany, a paratype is a specimen of an organism that helps define what the scientific name of a species and other taxon actually represents, but it is not the holotype (and in botany is also neither an isotype (biology), isotype ...

s, are currently preserved in the Division of Invertebrate Zoology collections at the in

Stuttgart Stuttgart (; ; Swabian German, Swabian: ; Alemannic German, Alemannic: ; Italian language, Italian: ; ) is the capital city, capital and List of cities in Baden-Württemberg by population, largest city of the States of Germany, German state of ...

, Germany. The holotype and paratype fossils are composed of complete adult workers which were originally preserved in the same amber specimen along with a number of other insects. The specimen, now cut into smaller pieces, 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, northern

Dominican Republic The Dominican Republic is a country located on the island of Hispaniola in the Greater Antilles of the Caribbean Sea in the Atlantic Ocean, North Atlantic Ocean. It shares a Maritime boundary, maritime border with Puerto Rico to the east and ...

. 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 unicellular organism, single-celled organisms, members of a phylum or class (biology), class of Rhizarian protists characterized by streaming granular Ectoplasm (cell bio ...

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 fossils were first studied by paleoentomologist Maria De Andrade of the

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

. De Andrade's 1998 type description of the new species was published in the Swiss journal ''Mitteilungen der Schweizerischen Entomologischen Gesellschaft''. The

specific epithet In Taxonomy (biology), taxonomy, binomial nomenclature ("two-term naming system"), also called binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, both of which use Latin gramm ...

''hispaniolicus'' is in reference island of Hispaniola where the fossil was found.

Description

The ''Acanthostichus hispaniolicus'' specimens are well preserved, though each of the four show some distortion from the amber moving after entombment. The specimens have estimated body lengths between . The overall coloration of ''A. hispaniolicus'' is a light orange-brown, with some darkening on the mandibles, the tarsomeres and the tarsi. The mandibles have between 6 and 8 minute teeth followed by a preapical tooth a short gap, and the apical tooth. The mouth is bracketed by a pair of three segmented labial palps and a pair of two segmented maxillary palps. The bodies have a flattened appearance in side view with a smooth and shining appearance and minute reticulation on portions of the gaster. The sting is noted to be well developed and long.

References

External links

* {{Taxonbar, from=Q15122246 Dorylinae Fossil ant taxa Burdigalian life Miocene insects of North America Prehistoric insects of the Caribbean Fauna of Hispaniola Extinct animals of the Dominican Republic Insects of the Dominican Republic Dominican amber Fossil taxa described in 1998