Formicium
Encyclopedia
Formicium is an extinct collective genus
of giant ant
s in the Formicidae subfamily Formiciinae
. The genus currently contains three species, Formicium berryi, Formicium brodiei, and Formicium mirabile. All three species were described from Eocene aged sediments.
, however the two German species have been moved from Formicium and placed in the related genus Titanomyrma
as T. giganteum and T. simillimum respectively. The wingspan
of the females is among the largest known among ants. The species Formicium mirabile, named by Theodore D. A. Cockerell
in 1920, and Formicium brodiei, named by John O. Westwood
in 1854, are both known from fore-wings found in middle Eocene of Bournemouth
, Dorset, England. The third species named, Formicium berryi was named by Frank M. Carpenter
in 1929 from the middle Eocene Claiborne Formation in Puryear, Tennessee
, USA, though he misidentified the formation as the Wilcox Formation. F. berryi was the first described occurrence of the genus and, until 2011, the subfamily, in North America.
As the wing structure of Formicidae is very plastic and can vary greatly even within a species and size between males and females can be notably different, the description of fossil species from wings alone is problematic. With the removal of the two German species described from full body fossils in 2011, Dr. Bruce Archibald and coauthors changed Formicium from a nominal genus to collective genus. They suggested it be used to contain species described from wings which do not have enough detail to place into a nominal genus such as Titanomyrma. As a collective genus, it does not contain a type species
per the International Code of Zoological Nomenclature
, but is still retained as the type genus for the subfamily Formiciinae.
Formicium berryi was originally described as Eoponera berryi by Frank Carpenter and placed in the extant subfamily Ponerinae
. This was based on the idea that the new species was related to the modern genus Dinoponera
. When initially described by Theodore D. A. Cockerell, Formicium mirabilis was placed in the monotypic genus Megapterites. At that time he considered the species to be part of the family Pseudosiricidae. This placement was retained in the Treatise on Invertebrate Paleontology
Hymenoptera section written by Frank Carpenter. This placement, however did not reflect the changes made by German paleoentomologist Herbert Lutz who synonymized Eoponera into Formicium in 1986 while describing the subfamily Formiciinae and the two German species. His 1990 synonymy of Megapterites into Formicium was also not reflected in the Treatise. Currently both genus names, Megapterites and Eoponera are accepted as junior synonyms of Formicium.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of giant ant
Ant
Ants are social insects of the family Formicidae and, along with the related wasps and bees, belong to the order Hymenoptera. Ants evolved from wasp-like ancestors in the mid-Cretaceous period between 110 and 130 million years ago and diversified after the rise of flowering plants. More than...
s in the Formicidae subfamily Formiciinae
Formiciinae
Formiciinae is an extinct subfamily of ants known from Eocene deposits in Europe and North America.-Genera:The type genus is Formicium with the genus Titanomyrma being described in 2011. Formicium includes the described species which are known from fossil wings only. Formicium is known from three...
. The genus currently contains three species, Formicium berryi, Formicium brodiei, and Formicium mirabile. All three species were described from Eocene aged sediments.
History and classification
Formicium was originally described from isolated fossil forewings, with full queens, drones, and workers being described from Germany later. Until 2011, the genus included five speciesSpecies
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
, however the two German species have been moved from Formicium and placed in the related genus Titanomyrma
Titanomyrma
Titanomyrma was a genus of giant ant. The latest species to be discovered, T. lubei, was described in 2011, when a fossilized winged queen ant, comparable in size to hummingbirds, was found in Wyoming. This fossil is the first body of a giant ant found in the Western Hemisphere...
as T. giganteum and T. simillimum respectively. The wingspan
Wingspan
The wingspan of an airplane or a bird, is the distance from one wingtip to the other wingtip. For example, the Boeing 777 has a wingspan of about ; and a Wandering Albatross caught in 1965 had a wingspan of , the official record for a living bird.The term wingspan, more technically extent, is...
of the females is among the largest known among ants. The species Formicium mirabile, named by Theodore D. A. Cockerell
Theodore Dru Alison Cockerell
Theodore Dru Alison Cockerell was an American zoologist, born at Norwood, England, and brother of Sydney Cockerell. He was educated at the Middlesex Hospital Medical School, and then studied botany in the field in Colorado in 1887-90...
in 1920, and Formicium brodiei, named by John O. Westwood
John Obadiah Westwood
John Obadiah Westwood was an English entomologist and archaeologist also noted for his artistic talents.Born in Sheffield, he studied to be a lawyer but abandoned that for his scientific interests....
in 1854, are both known from fore-wings found in middle Eocene of Bournemouth
Bournemouth
Bournemouth is a large coastal resort town in the ceremonial county of Dorset, England. According to the 2001 Census the town has a population of 163,444, making it the largest settlement in Dorset. It is also the largest settlement between Southampton and Plymouth...
, Dorset, England. The third species named, Formicium berryi was named by Frank M. Carpenter
Frank M. Carpenter
Frank M. Carpenter received his PhD from Harvard University, and was curator of fossil insects at the Harvard Museum of Comparative Zoology for 60 years. He studied the Permian fossil insects of Elmo, Kansas, and compared the North American fossil insect fauna with Paleozoic taxa known from...
in 1929 from the middle Eocene Claiborne Formation in Puryear, Tennessee
Puryear, Tennessee
Puryear is a city in Henry County, Tennessee, United States. The population was 667 at the 2000 census.-Geography:Puryear is located at .According to the United States Census Bureau, the city has a total area of , all of it land....
, USA, though he misidentified the formation as the Wilcox Formation. F. berryi was the first described occurrence of the genus and, until 2011, the subfamily, in North America.
As the wing structure of Formicidae is very plastic and can vary greatly even within a species and size between males and females can be notably different, the description of fossil species from wings alone is problematic. With the removal of the two German species described from full body fossils in 2011, Dr. Bruce Archibald and coauthors changed Formicium from a nominal genus to collective genus. They suggested it be used to contain species described from wings which do not have enough detail to place into a nominal genus such as Titanomyrma. As a collective genus, it does not contain a type species
Type species
In biological nomenclature, a type species is both a concept and a practical system which is used in the classification and nomenclature of animals and plants. The value of a "type species" lies in the fact that it makes clear what is meant by a particular genus name. A type species is the species...
per the International Code of Zoological Nomenclature
International Code of Zoological Nomenclature
The International Code of Zoological Nomenclature is a widely accepted convention in zoology that rules the formal scientific naming of organisms treated as animals...
, but is still retained as the type genus for the subfamily Formiciinae.
Formicium berryi was originally described as Eoponera berryi by Frank Carpenter and placed in the extant subfamily Ponerinae
Ponerinae
Ponerinae is a subfamily of ants in the Poneromorph subfamilies group, with about 1,600 species in 28 extant genera, including Dinoponera gigantea - one of the world's largest species of ant....
. This was based on the idea that the new species was related to the modern genus Dinoponera
Dinoponera gigantea
Dinoponera gigantea is one of the world's largest species of ant. It is found only in South America. The females of the species are larger than males, with lengths ranging from . The females are coal-black in color, while the much smaller males are dark red.-Nesting:D. gigantea colonies have as...
. When initially described by Theodore D. A. Cockerell, Formicium mirabilis was placed in the monotypic genus Megapterites. At that time he considered the species to be part of the family Pseudosiricidae. This placement was retained in the Treatise on Invertebrate Paleontology
Treatise on Invertebrate Paleontology
The Treatise on Invertebrate Paleontology published by the Geological Society of America and the University of Kansas Press, is a definitive multi-authored work of some 50 volumes, written by more than 300 paleontologists, and covering every phylum, class, order, family, and genus of fossil and...
Hymenoptera section written by Frank Carpenter. This placement, however did not reflect the changes made by German paleoentomologist Herbert Lutz who synonymized Eoponera into Formicium in 1986 while describing the subfamily Formiciinae and the two German species. His 1990 synonymy of Megapterites into Formicium was also not reflected in the Treatise. Currently both genus names, Megapterites and Eoponera are accepted as junior synonyms of Formicium.