Nylanderia pygmaea Temporal range: | |
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Nylanderia pygmaea syntype male from the Prussian Formation, Kaliningrad Oblast, Russia | |
Scientific classification ![]() | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Arthropoda |
Class: | Insecta |
Order: | Hymenoptera |
Family: | Formicidae |
Subfamily: | Formicinae |
Genus: | Nylanderia |
Species: | N. pygmaea |
Binomial name | |
Nylanderia pygmaea (Mayr, 1868) | |
Synonyms | |
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Nylanderia pygmaea is an extinct species of formicid in the ant subfamily Formicinae known from fossils found in the Prussian Formation of the Baltic region.
When described N. pygmaea was known from twenty males and two queen fossils which were fossilized as inclusions in transparent chunks of Baltic amber [1] [2] almost all of which are now presumed lost. [1] Additional individuals of all castes have since been found in Baltic, Bitterfeld, Rovno, and Scandinavian amber. [3] [4]
Baltic amber is approximately forty six million years old, having been deposited during Lutetian stage of the Middle Eocene. There is debate on by what plant family the amber was produced, with macrofossil and microfossil evidence suggesting a Pinus relative, while chemical and spectroscopic evidence suggests Agathis or Sciadopitys . [5] [6] The paleoenvironment of the Eocene Baltic forests where the P. eocenicum lived was that of humid temperate to subtropical islands. The forests were composed of mostly Quercus and Pinus species, while the lower sections of the forests had paratropical plant elements, such as palms. [5] Rovno amber, recovered from deposits in the Rivne region of Ukraine, is slightly younger in age, being dated to the Bartonian to Priabonian of the Late Eocene. [7] Bitterfeld amber is recovered from coal deposits in the Saxony area of Germany and the dating of the deposits is uncertain. Bitterfeld represents a section of the Eocene Paratethys Sea, and the amber that is recovered from the region is thought to be redeposited from older sediments. The fossil record of Bitterfeld and Baltic amber insects is very similar with a number of shared species, and that similarity is noted in the suggestions of a single source for the paleoforest that produced the amber. [8] The amber deposits on the Danish coast, often referred to as Scandinavian amber, is of similar age to the other three European ambers, however a study of the ant fauna published in 2009 indicates Scandinavian amber has a fairly distinct ant assemblage. [3]
The species was first described in 1868 by Austrian entomologist Gustav Mayr based on twenty males and two queens. He named the species and placed it into the genus Prenolepis as Prenolepis pygmaea. [9] [1] The species was briefly re-examined in 1915 by William Morton Wheeler based on a group of 57 males and 3 queens, including 10 of Mayr's original male syntypes and 1 gyne syntype. Mayr's placement was unchanged until 2009 when the species was moved by Gennady Dlussky and Alexandr Rasnitsyn. Dlussky and Rasnitsyn noted that when the species was described by both Mayr and Wheeler Prenolepis and Paratrechina were considered a single genus, which was later separated by Carlo Emery in 1925, leaving the fossil species in Prenolepis. Based on the character states observed by Dlussky and Rasnitsyn they moved the species to Paratrechina. [3] Fossil species belonging to the Prenolepis genus group were again examined and reviewed in 2010 by John LaPolla and Gennady Dlussky. Based on the mandible, pronotal structure and mesonotal setae they moved the species to Nylanderia , noting the species to be the oldest in the genus. [1]
N. pygmaea is known primarily by winged males and females, a situation also seen in several Ponerinae species in Baltic, Bitterfeld, and Scandinavian ambers. Modern Nylanderia and the ponerinae species from Gnamptogenys , Hypoponera , Pachycondyla , Ponera , and Proceratium are all ground dwelling and nesting species, whose workers rarely climb high into trees. Due to this, the workers of the amber forest species would not often come into contact with fresh resin to be entombed. However, in all of the genera, the winged queens and males would climb plants and trees surrounding the nests during the nuptial flight increasing greatly the contact with fresh resin and entrapment. [3] [10]
An investigation of Baltic, Bitterfeld, Scandinavian, and Rovno ambers in 2009 showed over 90% of N. pygmaea specimens in Baltic, Scandinavian and Bitterfeld ambers were alates, while still being a very small component of the ant faunas. In Baltic amber N. pygmaea was between 0.51% and 0.71% of all ants, and in Bitterfeld the species was only 1.26%. In contrast Rovno amber showed a larger percentage at 3.03% and Scandinavian had the highest percentage 3.66%, which was suggested to relate possibly to habitat humidity. [3]
Workers are between 1.5–1.6 mm (0.059–0.063 in) long with a shiny brown exoskeleton. There are setae along the rear edge of the head, two pairs of upright setae on the pronotum, another pair on the mesonotum and the gaster has scattered upright setae. The heads are rectangular in outline, being slightly narrower than long, and have a faintly concave to straight rear margin. The first segment of the antennae, the scape, extends past the rear edge of the head. They have a compact mesosoma that has a distinct metanotal sclerite and a gently curved propodeum. [1]
Males are a little larger than the workers, with a length between 1.5–1.7 mm (0.059–0.067 in) [2] reported by Wheeler in 1915 and between 1.7–1.9 mm (0.067–0.075 in) reported by LaPolla in 2010. [1]
The Formicinae are a subfamily within the Formicidae containing ants of moderate evolutionary development.
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.
Paratrechina is one of seven ant genera in the Prenolepis genus-group from the subfamily Formicinae. Six species are included in Paratrechina; one of which, the longhorn crazy ant, is a widespread, pantropical pest.
The Baltic region is home to the largest known deposit of amber, called Baltic amber or succinite. It was produced sometime during the Eocene epoch, but exactly when is controversial. It has been estimated that these forests created more than 100,000 tons of amber. Today, more than 90% of the world's amber comes from Kaliningrad Oblast of Russia. It is a major source of income for the region; the local Kaliningrad Amber Combine extracted 250 tonnes of it in 2014 and 400 tonnes in 2015.
Prionomyrmex is an extinct genus of bulldog ants in the subfamily Myrmeciinae of the family Formicidae. It was first described by Gustav Mayr in 1868, after he collected a holotype worker of P. longiceps in Baltic amber. Three species are currently described, characterised by their long mandibles, slender bodies and large size. These ants are known from the Eocene and Late Oligocene, with fossil specimens only found around Europe. It is suggested that these ants preferred to live in jungles, with one species assumed to be an arboreal nesting species. These ants had a powerful stinger that was used to subdue prey. In 2000, it was suggested by Cesare Baroni Urbani that the living species Nothomyrmecia macrops and a species he described both belonged to Prionomyrmex, but this proposal has not been widely accepted by the entomological community. Instead, scientists still classify the two genera distinctive from each other, making Nothomyrmecia a valid genus.
Nylanderia is a large genus of ants in the subfamily Formicinae. The genus has a nearly cosmopolitan distribution with species inhabiting a wide array of habitats in almost all geographic regions. Nylanderia, currently containing over 110 species, is an ecologically important genus, with some species reported as being invasive. The ants are small to medium in size and range in color from pale yellow to black.
Gesomyrmex is a genus of ants in the subfamily Formicinae. The genus contains six extant species, known from the Indomalayan realm, and nine fossil species. Of the extant species, four are known only from workers and two only from females. The extinct species "G. expectans" and "Gesomyrmex miegi", formerly placed in the genus, were excluded by Dlussky et al.., 2009.
Pristomyrmex rasnitsyni is an extinct species of ant in the genus Pristomyrmex. The species is known from a single Late Eocene fossil which was found in Europe.
Aphaenogaster sommerfeldti is an extinct species of ant in the subfamily Myrmicinae known from a group of Middle Eocene fossils found in Europe. A. sommerfeldti is one of three species in the ant genus Aphaenogaster to have been noted from fossils found in Baltic amber by William Morton Wheeler.
Aphaenogaster mersa is an extinct species of ant in the subfamily Myrmicinae known from a pair of Middle Eocene fossils found in Europe. A. mersa is one of three species in the ant genus Aphaenogaster to have been noted from fossils found in Baltic amber by William Morton Wheeler.
Usomyrma is an extinct genus of ant in the formicid subfamily Dolichoderinae. The genus contains a single described species, Usomyrma mirabilis, that is known from two Middle Eocene fossils which were found in Scandinavian amber in Denmark.
Yantaromyrmex is an extinct genus of ants first described in 2013. Members of this genus are in the subfamily Dolichoderinae of the family Formicidae, known from Middle Eocene to Early Oligocene fossils found in Europe. The genus currently contains five described species, Y. constrictus, Y. geinitzi, Y. intermedius, Y. mayrianum and Y. samlandicus. The first specimens were collected in 1868 and studied by Austrian entomologist Gustav Mayr, who originally placed the fossils in other ant genera until the fossils were reviewed and subsequently placed into their own genus. These ants are small, measuring from 4 to 6 mm in length and can be characterized by their trapezoidal shaped head-capsules and oval compound eyes that are located slightly to the rear of the capsules midpoint, with no known ocelli present.
Zherichinius is an extinct genus of ants in the subfamily Dolichoderinae known from fossils found in amber from the Middle Eocene of Sakhalin island Far eastern Russia and Bitterfeld, Germany. At the time of description the species Zherichinius horribilis and Zherichinius rapax were two of eight ant species known from Sakhalin fossils.
This list of fossil arthropods described in 2009 is a list of new taxa of trilobites, fossil insects, crustaceans, arachnids and other fossil arthropods that have been described during the year 2009, as well as other significant discoveries and events related to arthropod paleontology that occurred.
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.
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.
Proceratium eocenicum is an extinct species of formicid in the ant subfamily Proceratiinae known from fossils found in the Baltic region.
Pachycondyla succinea is an extinct species of ant in the formicid subfamily Ponerinae described from fossils found in Europe. P. petrosa is one of three middle Eocene Pachycondyla species found in Baltic amber.