Cyrtopone Temporal range: | |
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C. microcephala holotype | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Arthropoda |
Class: | Insecta |
Order: | Hymenoptera |
Family: | Formicidae |
Subfamily: | Ponerinae |
Tribe: | Ponerini |
Genus: | † Cyrtopone Dlussky & Wedmann, 2012 |
Type species | |
Cyrtopone microcephala | |
Species | |
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Cyrtopone is an extinct genus of ants in the formicid subfamily Ponerinae described from fossils found in Europe. There are four described species placed into the genus, Cyrtopone curiosa, Cyrtopone elongata, Cyrtopone microcephala, and Cyrtopone striata. Cyrtopone is one several Lutetian Ponerinae genera. [1]
When described, Cyrtopone was known from four fossil insects which are compression-impression fossils preserved in layers of soft sedimentary rock. [1] Along with other well preserved insect fossils, the Cyrtopone specimens were collected from layers of the Lutetian Messel pit World Heritage Site. The formation is composed of brown coals, oil shales, and bituminous shale, which preserved numerous insects, fish, birds, reptiles, and terrestrial mammals as a notable lagerstätten. The area is a preserved maar lake which initially formed approximately 47 million years ago as the result of volcanic explosions. [2]
At the time of description, the four holotype specimens were preserved in the Senckenberg Research Station Messel fossil collections. The fossils were described by Gennady Dlussky and Sonja Wedmann in a 2012 paper on the poneromorph ants of Messel, with the genus and four species named in it. [1] The genus name is a combination of the ant genus Ponera and the Greek word cyrtos, meaning curved. [1]
Cyrtopone is one of five extinct genera from three subfamilies which have species described from Messel Formation fossils by Dlussky and Wedmann in 2012. Three of the other genera Cephalopone , Messelepone , and Protopone are also placed in Ponerinae. The genus Casaleia is placed in Amblyoponinae, while the last genus Pseudectatomma is in Ectatomminae. [1]
The Cyrtopone queens from Messel are described as having approximate body lengths ranging between 6.2–14.7 millimetres (0.24–0.58 in). Species have heads that are distinctly small, [1] the mesosoma being about 2 times greater in length. The subtriangular mandibles are up to one half the head length and have toothed chewing faces. Like Protopone species, the antennae sockets are widely placed on the head, in contrast to those seen in Pachycondyla which are close together. The node shaped petiole is shorter than the height, with a helcium that projects of the front face of the gasteral segment. [1]
The only C. curiosa fossil is of a wingless gyne preserved in profile view with a body about 7.5 mm (0.30 in) long. The head is slightly rectangular and 1.8 times shorter than the mesosoma. The sides are mostly straight, while the back corners are rounded the back edge is convex and the eyes are placed just behind the middle point of the head. The antennae have a scape which reaches just past the back edge of the head. The frons stretches across a quarter of the head front. The mesosoma is massive, and 3.2 times longer than the scutum. The species name "curiosa" is derived from the Latin curiosus which means funny. [1]
The described C. elongata fossil is the only queen preserved as dorsal impression. The body length of the winged queen is approximately 5.7 mm (0.22 in) long with a node shaped petiole and a mesosoma that is double the length of the head. As with C. curiosa, the head has nearly parallel sides rounded back corners and a convex back margin, though the head in C. elongata is distinctly rectangular. The oval eyes are placed just to the front of the heads midpoint and the gena are bigger than the maximum eye width. The antennae have a scape which reaches the back edge of the head, while the segments gradually thicken from scape to tip. but they do not form a distinct club at the tip. Each of the antenna segments are about the same width as they are long. The mandibles are approximately 45% to 50% the length of the head. Dlussky and Wedmann coined the species name elongata from the Latin "elongates" meaning elongated. [1]
C. microcephala is known from a single fossil, a winged gyne preserved in profile view. The body has an approximate length of 12.5 mm (0.49 in) with an essentially square head. The head is 1.5 times shorter than the mesosoma and has a sculpturing of small pits. The clypeus has a trapezohedral shape to the lower edge, and the eyes are placed at the middle point of the head. The antennae have segments that are 2 times as long as they are wide, with a scape which reaches to the back edge of the head. The mandibles are small, being under half the head length and each chewing side is toothed. The species name is taken from the Greek "microcephalos", which translates to "with a small head". [1]
The largest of the Cyrtopone species, C. striata has a body length of about 14.5 mm (0.57 in) and has the biggest difference between head and mesosoma, the head being 2.5 times shorter. The winged gyne is a dorsal impression showing distinct sculpturing on the head and scutum made of longitudinal ridges. The eyes are small, placed near the center of the head, and the gena below them are nearly one and a half times longer than the eye diameter. The scape is longer than in the other species with one third of its length extending past the back margin of the head. The metatibiae shows two spurs, a simple and a pectinate one. [1]
Ponerinae, the ponerine ants, is a subfamily of ants in the Poneromorph subfamilies group, with about 1,600 species in 47 extant genera, including Dinoponera gigantea - one of the world's largest species of ant. Mated workers have replaced the queen as the functional egg-layers in several species of ponerine ants. In such queenless species, the reproductive status of workers can only be determined through ovarian dissections.
Gesomyrmex pulcher is an extinct species of ant in the subfamily Formicinae known from an Eocene fossil found in Europe. G. pulcher is one of only eight species in the ant genus Gesomyrmex to have been described from fossils found in Europe.
Ypresiomyrma is an extinct genus of ants in the subfamily Myrmeciinae that was described in 2006. There are four species described; one species is from the Isle of Fur in Denmark, two are from the McAbee Fossil Beds in British Columbia, Canada, and the fourth from the Bol’shaya Svetlovodnaya fossil site in Russia. The queens of this genus are large, the mandibles are elongated and the eyes are well developed; a stinger is also present. The behaviour of these ants would have been similar to that of extant Myrmeciinae ants, such as solitary foraging for arthropod prey and never leaving pheromone trails. The alates were poor flyers due to their size, and birds and animals most likely preyed on these ants. Ypresiomyrma is not assigned to any tribe, and is instead generally regarded as incertae sedis within Myrmeciinae. However, some authors believe Ypresiomyrma should be assigned as incertae sedis within Formicidae.
The Messel Formation is a geologic formation in Hesse, central Germany, dating back to the Eocene epoch. Its geographic range is restricted to the Messel pit. There it unconformably overlies crystalline Variscan basement and its Permian cover (Rotliegend) as well as Eocene volcanic breccias derived from the basement rocks. The formation mainly comprises lacustrine laminated bituminous shale renowned for its content of fossils in exceptional preservation, particularly plants, arthropods and vertebrates.
Archimyrmex is an extinct genus of ant in the formicid subfamily Myrmeciinae, described by palaeoentomologist Theodore Cockerell in 1923. The genus contains four described species, Archimyrmex rostratus, Archimyrmex piatnitzkyi, Archimyrmex smekali and Archimyrmex wedmannae. Archimyrmex is known from a group of Middle Eocene fossils which were found in North America, South America, and Europe. The genus was initially placed in the subfamily Ponerinae, but it was later placed in Myrmeciinae; it is now believed to be the ancestor of the extant primitive genus Myrmecia from Australia. Despite this, Archimyrmex is not a member to any tribe and is regarded as incertae sedis within Myrmeciinae. However, some authors believe Archimyrmex should be assigned as incertae sedis within Formicidae. These ants can be characterised by their large mandibles and body length, ranging from 13.2 to 30 mm. They also have long, thin legs and an elongated mesosoma (thorax) and petiole.
Archiponera is an extinct genus of ant in the formicid subfamily Ponerinae. The genus contains a single described species, Archiponera wheeleri known from several Late Eocene fossils which were found in North America.
Emplastus is an extinct morphogenus of ants in the subfamily Dolichoderinae, known from fossils found in Asia and Europe. The genus contains twelve species described from sites in England, Eastern Europe and Far Eastern Russia.
Casaleia is an extinct genus of ants in the formicid subfamily Amblyoponinae described by Pagliano & Scaramozzino in 1990 from fossils found in Europe. The genus contains four species dating from the Eocene to Miocene, Casaleia eocenica, Casaleia inversa, Casaleia longiventris, Casaleia orientalis.
Pseudectatomma is an extinct genus of ants in the formicid subfamily Ectatomminae described by from fossils found in Europe. The genus contains two species dating from the Eocene, Pseudectatomma eocenica and Pseudectatomma striatula.
Pachycondyla eocenica is an extinct species of ant in the formicid subfamily Ponerinae described from fossils found in Europe. P. eocenica is one of six Lutetian Pachycondyla species.
Pachycondyla lutzi is an extinct species of ant in the formicid subfamily Ponerinae described by from fossils found in Europe. P. lutzi is one of six Lutetian Pachycondyla species.
Pachycondyla? messeliana is an extinct species of ants in the formicid subfamily Ponerinae described by from a fossil found in Europe. P.? messeliana is one of six Lutetian Pachycondyla species.
Pachycondyla parvula is an extinct species of ant in the formicid subfamily Ponerinae described by from a fossil found in Europe. P. parvula is one of six Lutetian Pachycondyla species.
Pachycondyla petiolosa is an extinct species of ant in the formicid subfamily Ponerinae described by from a fossil found in Europe. P. parvula is one of six Lutetian Pachycondyla species.
Pachycondyla petrosa is an extinct species of ant in the formicid subfamily Ponerinae described from a fossil found in Europe. P. petrosa is one of six Lutetian Pachycondyla species.
Protopone is an extinct genus of ants in the formicid subfamily Ponerinae described from fossils found in Europe and Asia. There are seven described species placed into the genus, Protopone? dubia, Protopone germanica, Protopone magna, Protopone oculata, Protopone primigena, Protopone sepulta, and Protopone vetula. Protopone is one several Lutetian Ponerinae genera.
Cephalopone is an extinct genus of ants in the formicid subfamily Ponerinae described from fossils found in Europe. There are two described species placed into the genus, Cephalopone grandis and Cephalopone potens. Cephalopone is one several Lutetian Ponerinae genera.
Messelepone is an extinct genus of ants in the formicid subfamily Ponerinae described from fossils found in Europe. M. leptogenoides is the only species assigned to the genus, which is one of several Lutetian Ponerinae genera.
Aneuretellus is an extinct genus of ant in the formicid subfamily Aneuretinae, and is one of eight genera of the subfamily. The genus contains a single described species Aneuretellus deformis and is known from one Middle Eocene fossil which was found in Sakhalin in the Russian Far East.
Bradoponera is an extinct genus of ant in the Formicidae subfamily Proceratiinae, and is one of four genera of the subfamily. The genus contains four described species Bradoponera electrina, Bradoponera meieri, Bradoponera similis, and Bradoponera wunderlichi. The species are known from several Middle Eocene amber fossils which were found in Europe.