''Cephalotes hispaniolicus'' 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

Myrmicinae Myrmicinae is a subfamily of ants, with about 140 extant genera; their distribution is cosmopolitan. The pupae lack cocoons. Some species retain a functional sting. The petioles of Myrmicinae consist of two nodes. The nests are permanent and ...

known from a single

Middle Miocene The Middle Miocene is a sub-epoch of the Miocene Epoch made up of two stages: the Langhian and Serravallian stages. The Middle Miocene is preceded by the Early Miocene. The sub-epoch lasted from 15.97 ± 0.05 Ma to 11.608 ± 0.005 Ma (million y ...

fossil found in

amber Amber is fossilized tree resin that has been appreciated for its color and natural beauty since Neolithic times. Much valued from antiquity to the present as a gemstone, amber is made into a variety of decorative objects."Amber" (2004). In Ma ...

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 ...

. At the time of description ''C. hispaniolicus'' was one of six ant species placed in the ''Cephalotes'' ''multispinosus'' clade.

History and classification

''C. hispaniolicus'' was described from a solitary fossil worker caste ant which was preserved as 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 chunk of

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 ...

. The amber was produced by the extinct tree ''

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 Hispaniola, across northern South America and up to southern Mexico. The specimen was collected from an unidentified amber mine in the

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 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 ...

age of the Miocene, being recovered from sections of the

La Toca Formation The La Toca Formation is a geologic formation in the northern and eastern part of the Dominican Republic. The formation, predominantly an alternating sequence of marls and turbiditic sandstones, breccias and conglomerates, is renowned for the p ...

in 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 ...

and the

Yanigua Formation The Yanigua Formation is a geologic formation in Dominican Republic. The lagoonal claystones and marls preserve fossils dating back to the Miocene period.Cordillera Oriental. 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 collections of 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 ...

in Germany. Living and fossil ''Cephalotes'', ''Eucryptocerus'', ''Exocryptocerus'' and ''Zacryptocerus'' ants were examined in 1999 by Maria L. De Andrade and Cesare Baroni Urbani with a redescription of included species being published in the journal ''Stuttgarter Beiträge zur Naturkunde. Serie B (Geologie und Paläontologie)''. The fossil was first described in the paper along with a number of fossils and was placed into the new species ''Cephalotes hispaniolicus''. De Andrade and Baroni Urbani coined 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 ...

''hispaniolicus'' as a

neologism A neologism Greek νέο- ''néo''(="new") and λόγος /''lógos'' meaning "speech, utterance"] is a relatively recent or isolated term, word, or phrase that may be in the process of entering common use, but that has not been fully accepted int ...

referring to the island of origin for the amber and species, Hispaniola.

Phylogeny

Cephalotes hispaniolicus SMNSDO4163 head

In the study of ''Cephalotes'' by de Andrade and Baroni Urbani, ''C. hispaniolicus'' was grouped into the ''multispinosus'' clade which is composed of three extinct species and three extant species. The clade shares only one distinct feature between the species; unlike other clades, ''multispinosus'' species have reduced lamellar expansions on the sides of the

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 ...

. ''C. hispaniolicus'' is distinguished from the first outgroup member of the clade '' Cephalotes poinari'' based on the shape of the propodial lamellar projections, but is closer in relation to it than to the other Dominican amber species in the clade, '' Cephalotes squamosus''. ''C. hispaniolicus'' has the second highest cephalic index in the clade; only ''C. poinari'' has a greater one.

Description

The lone worker of ''C. hispaniolicus'' has a body length of , a head length of and a cephalic index that is 142.8. The overall body color is black, with four lighter colored spots, two on the head and two on 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 ...

. The lamellae along the gaster,

, and pronotum along with the ridges along the front of the face are all dark brown and semitransparent. The head has minute punctate, with clumped pits that grow smaller towards the front of the head. The mesosoma, propodium, legs and gaster have a reticulated sculpturing to the exoskeleton, with pits in the centers of the reticulations. Similarly the peduncular segments are reticulated with pits, though the reticulation is denser than on the propodium. The center of the first gastral

sternite The sternum (pl. "sterna") is the ventral portion of a segment of an arthropod thorax or abdomen. In insects, the sterna are usually single, large sclerites, and external. However, they can sometimes be divided in two or more, in which case the ...

is distinctly shiny. Each of the pits has a thin hair growing from it and which lies flat along the exoskeleton, and similar hairs are present on the gaster. Variously sized clubbed hairs are scattered along the rear borders of both the gastral tergites and sternites, while similar, but minutely sized clubbed hairs are rarely found on the rear corners of the head. The propodium has narrow lamellae along the posterior sides that project out and then taper towards the rear. The petiole and post petiole segments each have triangular semi-transparent lamellae on the sides, with the post petiole lamellae bracketed by the lamellae projecting from the front of the gaster.

References

External links

* {{Taxonbar, from=Q5063405 hispaniolicus Fossil ant taxa Miocene insects Burdigalian life Hymenoptera of North America Prehistoric insects of the Caribbean Fauna of Hispaniola Neogene Dominican Republic Fossils of the Dominican Republic Insects of the Dominican Republic Extinct animals of the Dominican Republic Dominican amber Fossil taxa described in 1999 Insects described in 1999