''Electromyrmococcus'' 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 ...

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

mealybug Mealybugs are insects in the family Pseudococcidae, unarmored scale insects found in moist, warm habitats. Of the more than 2,000 described species, many are considered pests as they feed on plant juices of greenhouse plants, house plants and ...

in the

Pseudococcidae Mealybugs are insects in the family Pseudococcidae, unarmored scale insects found in moist, warm habitats. Of the more than 2,000 described species, many are considered pests as they feed on plant juices of greenhouse plants, house plants and su ...

subfamily Rhizoecinae. The genus currently contains three species, all from the early

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 ...

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,

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 ...

deposits on the 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 ...

History and classification

The genus was first described by Douglas Williams as an appendix to a 2001 paper published in the journal ''

American Museum Novitates ''American Museum Novitates'' is a peer-reviewed academic journal published by the American Museum of Natural History. It was established in 1921. According to the ''Journal Citation Reports'', the journal has a 2013 impact factor The impact ...

''. The genus name is a combination of ''electro'', from the

Greek Greek may refer to: Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group *Greek language, a branch of the Indo-European language family **Proto-Greek language, the assumed last common ancestor of all kno ...

(') meaning "

amber Amber is fossilized tree resin. Examples of it have been appreciated for its color and natural beauty since the Neolithic times, and worked as a gemstone since antiquity."Amber" (2004). In Maxine N. Lurie and Marc Mappen (eds.) ''Encyclopedia ...

", ''myrmo'' from the Greek (') meaning "ant" and ''

Coccus Bacterial cellular morphologies are the shapes that are characteristic of various types of bacteria and often key to their identification. Their direct examination under a light microscope enables the classification of these bacteria (and archaea ...

'' from the ant-tended genus of mealybugs, in reference to the association of ant and mealybugs in amber. Along with the genus description, the paper contained the description of the

type Type may refer to: Science and technology Computing * Typing, producing text via a keyboard, typewriter, etc. * Data type, collection of values used for computations. * File type * TYPE (DOS command), a command to display contents of a file. * ...

species ''E. abductus'' and the two additional species ''E. inclusus'' and ''E. reginae''.

Description

''Electromyrmococcus'' possesses a combination of traits which are not found in any one

modern Modern may refer to: History *Modern history ** Early Modern period ** Late Modern period *** 18th century *** 19th century *** 20th century ** Contemporary history * Moderns, a faction of Freemasonry that existed in the 18th century Philosophy ...

genus belonging to the Rhizoecinae, a subfamily of the mealybugs. Living Rhizoecinae are separated into two groups of closely related genera, the ''Rhizoceus'' group and the ''Eumyrmococcus'' group. Antennae of the ''Rhizoceus'' group have six segments, at least as wide as they are long. The antennae of the ''Eumyrmococcus'' group have two to five long slender segments. ''Electromyrmococcus'' has long slender antennae with six segments. ''Electromyrmococcus'' species have an enlarged

cephalothorax The cephalothorax, also called prosoma in some groups, is a tagma of various arthropods, comprising the head and the thorax fused together, as distinct from the abdomen behind. (The terms ''prosoma'' and ''opisthosoma'' are equivalent to ''cepha ...

and an abdomen that gradually tapers down to a pointed end. Along the last segments of the abdomen are a number of

seta In biology, setae (; seta ; ) are any of a number of different bristle- or hair-like structures on living organisms. Animal setae Protostomes Depending partly on their form and function, protostome setae may be called macrotrichia, chaetae, ...

e which may be grouped on small poorly developed anal lobes or spaced out on the ventral margin of the abdominal segment. All known specimens of ''Electromyrmococcus'' are preserved in amber, and all are either being clutched in the

mandible In jawed vertebrates, the mandible (from the Latin ''mandibula'', 'for chewing'), lower jaw, or jawbone is a bone that makes up the lowerand typically more mobilecomponent of the mouth (the upper jaw being known as the maxilla). The jawbone i ...

s of ''

Acropyga glaesaria ''Acropyga glaesaria'' is an extinct species of ant in the subfamily Formicinae known from a group of possibly Miocene fossils found on Hispaniola. ''A. glaesaria'' is the first species of the ant genus '' Acropyga'' to have been described from ...

'' species ants, or in other close association with them. Mealybugs in the Rhizoecinae subfamily are often obligatorily symbiotic with ''Acropyga'' species; when forming new nests the

queens Queens is the largest by area of the Boroughs of New York City, five boroughs of New York City, coextensive with Queens County, in the U.S. state of New York (state), New York. Located near the western end of Long Island, it is bordered by the ...

and

gyne The gyne (, from Greek γυνή, "woman") is the primary reproductive female caste of social insects (especially ants, wasps, and bees of order Hymenoptera, as well as termites). Gynes are those destined to become queens, whereas female workers ...

s will bring a seed "herd" of mealybugs from the old colony. This carrying behavior is the probable reason for the preservation of the ''Electromyrmococcus'' specimens and represents the oldest record of this symbiosis.

''E. abductus''

''E. abductus'' was described from 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 ...

, a single elongated piriform female long, clutched in the mandibles of an ''Acropyga glaesaria'' adult. Very weakly formed anal lobes are found on segment eight of the abdomen and each lobe has four setae. Setae are also present on the abdominal segments leading to segment eight. The amber was recovered from the La Toca mine group northeast of

Santiago de los Caballeros Santiago de los Caballeros ("James, son of Zebedee, Saint James of the Knights"), often shortened to Santiago, is the second-largest city in the Dominican Republic and the fourth-largest city in the Caribbean by population. It is the capital of ...

in the

Cibao Valley The Cibao, usually referred as El Cibao, is a region of the Dominican Republic located in the northern part of the country. As of 2009, the Cibao region has a population of 5,622,378, making it the most populous region in the country. The region ...

. The holotype is deposited in the

Senckenberg Museum The Naturmuseum Senckenberg () is a museum of natural history, located in Frankfurt am Main. It is the second-largest of its kind in Germany. In 2010, almost 517,000 people visited the museum, which is owned by the Senckenberg Nature Research S ...

Frankfurt Frankfurt am Main () is the most populous city in the States of Germany, German state of Hesse. Its 773,068 inhabitants as of 2022 make it the List of cities in Germany by population, fifth-most populous city in Germany. Located in the forela ...

Germany Germany, officially the Federal Republic of Germany, is a country in Central Europe. It lies between the Baltic Sea and the North Sea to the north and the Alps to the south. Its sixteen States of Germany, constituent states have a total popu ...

. The

species epithet Specific name may refer to: * in Database management systems, a system-assigned name that is unique within a particular database In Taxonomy (biology), taxonomy, either of these two meanings, each with its own set of rules: * Specific name (botany) ...

', which is

Latin Latin ( or ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken by the Latins (Italic tribe), Latins in Latium (now known as Lazio), the lower Tiber area aroun ...

for "carried off", was chosen by Williams in reference to the mealybug being preserved in the ant's mandibles.

''E. inclusus''

''E. inclusus'' is the second species which was named in the 2001 paper. The holotype female, and only specimen, is deposited in the

American Museum of Natural History The American Museum of Natural History (AMNH) is a natural history museum on the Upper West Side of Manhattan in New York City. Located in Theodore Roosevelt Park, across the street from Central Park, the museum complex comprises 21 interconn ...

as "

number A number is a mathematical object used to count, measure, and label. The most basic examples are the natural numbers 1, 2, 3, 4, and so forth. Numbers can be represented in language with number words. More universally, individual numbers can ...

DR-14–403". The female is long with a typical tapering abdomen. The abdomen has well-defined segments with segment eight possessing slightly developed anal lobes sporting four setae each, and segment two with a pair of submedial projections. The female has a notable constriction present between the abdomen and the thorax. However the constriction was probably not a feature possessed by the species in life, but rather thought to be a result of being compressed by the ant closely associated with it when they became trapped in

resin A resin is a solid or highly viscous liquid that can be converted into a polymer. Resins may be biological or synthetic in origin, but are typically harvested from plants. Resins are mixtures of organic compounds, predominantly terpenes. Commo ...

. Williams collaborated with Donat Agosti in the description of ''E. inclusus''. They chose the specific epithet ' which is a Latin participle meaning "enclosed" or "imprisoned" in allusion to the female's preservation in amber.

''E. reginae''

The third known species is ''E. reginae'', which, like the other known species, is known from a single female specimen preserved in amber. ''E. reginae'' is the largest of the three species at in length. Noted to be closely related to ''E. inclusus'', the anal lobes of ''E. reginae'' are not as well developed but do possess four setae each. The well-developed legs of ''E. reginae'' also have some setae present. Like ''E. abductus'' the ''E. reginae'' female was preserved in the mandibles of an ''Acropyga glaesaria'' ant, this one a queen. In reference to this the specific epithet ''reginae'' comes from the Latin ' meaning "belonging to a queen".

References

{{Taxonbar, from=Q16752647

† A dagger, obelisk, or obelus is a typographical mark that usually indicates a footnote if an asterisk has already been used. The symbol is also used to indicate death (of people) or extinction (of species or languages). It is one of the mo ...

Extinct Hemiptera Prehistoric insect genera Burdigalian life Miocene insects of North America Prehistoric insects of the Caribbean

Dominican amber Fossil taxa described in 2001