''Cephalotes caribicus'' 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 two

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 ...

fossils 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. caribicus'' was one of nine ant species placed in the ''Cephalotes'' ''pinelii'' clade.

History and classification

''Cephalotes caribicus'' was described based on two fossilised specimens which were preserved as

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 ...

s in transparent chunks 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 ''

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 specimens were 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 ...

stage 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.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 ...

, while the paratype was part of the George O. Poinar amber collections at

Oregon State University Oregon State University (OSU) is a public land-grant, research university in Corvallis, Oregon. OSU offers more than 200 undergraduate-degree programs along with a variety of graduate and doctoral degrees. It has the 10th largest engineering co ...

. 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 two fossils were first described in the paper along with a number of fossils and were placed into the new species ''Cephalotes caribicus''. 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 ...

''caribicus'' as a reference to region where the species was found.

Phylogeny

In the study of ''Cephalotes'' by De Andrade and Baroni Urbani, ''C. caribicus'' was grouped into the ''pinelii'' clade, which is composed of ''C. caribicus'' and eight extant species. The clade shares two distinct morphological features between the species and two coloration patterns. 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 ...

of ''pinelii'' clade species is modified with expansions of membrane, not seen in related clades. Additionally the antennae have a terminal club formed from the last two antennae segments rather than the last three segments. In the living species the gaster of the workers have a pair of spots or stripes and four spots are present on the gasters of gynes. Due to a fine layer of gas over the surface of each of the ''C. caribicus'' worker fossils in amber, the coloration was not distinguishable by De Andrade and Baroni Urbani, but color patterns were. ''C. caribicus'' was consistently placed as a sister species ''

Cephalotes incertus ''Cephalotes incertus'' is a species of arboreal ant of the genus '' Cephalotes'', characterized by an odd shaped head and the ability to "parachute" by steering their fall if they drop off of the tree they're on. Giving their name also as glid ...

'', both of which were nested deep in the clade.

Description

The two workers known have body lengths between , and heads that range between . Due to a thin film of gas over workers in both fossils, the coloration they may have had in life was not easily identifiable. The color patterning is visible and lighter colored spots on the head plus four lighter colored spots on the mesosoma are present, but the original coloration of the ants was not identifiable. The head is generally rectangular in outline, with broadly curved rear corners and having membranous extensions. The antennae have distinct apical clubs formed from the last two antenna segments. The first section of the mesosoma has large membrane extensions on the sides. The semitransparent expansions across the body are interpreted by De Andrade and Baroni Urbani as mechanisms to protect the body and appendages such as the antennae and legs from attack by other ants or arthropods. ''C. caribicus'' shares the feature of expanded membranous rear head corners with the modern species '' Cephalotes scutulatus'' of Central America.

References

External links

* {{Taxonbar, from=Q5063366

caribicus ''Caribicus'' is a genus of diploglossid lizards endemic to the island of Hispaniola in the Caribbean, in both the Dominican Republic and Haiti. Conservation All three species are considered threatened on the IUCN Red List, and one is possibly ...

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