Seppo koponeni Temporal range: Early Toarcian, | |
---|---|
Holotype and only known specimen MB.A 2966. | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Arthropoda |
Subphylum: | Chelicerata |
Class: | Arachnida |
Order: | Araneae |
Infraorder: | Araneomorphae |
Family: | incertae sedis |
Genus: | † Seppo Selden & Dunlop, 2014 |
Species: | †S. koponeni |
Binomial name | |
†Seppo koponeni Selden & Dunlop, 2014 | |
Seppo is an extinct genus of spiders, possibly of the superfamily Palpimanoidea, that lived about 180 million years ago, in the Early Jurassic (Lower Toarcian) of what is now Europe. The sole species Seppo koponeni is known from a single fossil from Grimmen, Germany. [1] With the scorpion Liassoscorpionides , it is one of the two only known arachnids from the Lower Jurassic of Germany. [1] Seppo is the first unequivocal Early Jurassic spider, and was recovered from the Green Series member of the Toarcian Ciechocinek Formation. [1]
The spider was described from a single female specimen. It is unknown if was an adult. [1] The carapace is unknown, and besides that has preserved bowed converging sides with a curved posterior margin with straight posterior border of the labium, with row of at least 12 peg teeth along the cheliceral furrow, no true teeth, scattered setae on anterior surface, and slender pedipalps. [1] Legs are preserved, the first and second being much longer than the third and fourth. All are well covered in setae and bristles, especially on the tibiae and metatarsi of leg I. [1] It most likely belongs to the Palpimanoidea, based on the presence of cheliceral peg teeth. [1]
The single known specimen was found on locality known for its fossil insects in Grimmen, near Greifswald, at the north of Germany. [1] It was reported in 2003, when Ansorge did a recompilation of insect taxa on the Toarcian strata of Germany and England. [2] The specimen was recovered from the Falciferum zone (Exaratum subzone), c. 180 Ma, and presented as "Araneae gen. et sp. nov." (Chelicerata). [2] It was recovered from a fragment of calcareous nodule from the grey-green claystone, recovered from the closed since the 90's clay pit of Klein Lehmhagen, near Grimmen, Western Pomerania, Germany. [2] [1] It is curious for being one of the rare few examples of spiders found on calcium carbonate (along with others from the Eocene limestone of the Isle of Wight, England [3] ). The specimen was found with some parts preserved as external moulds, and these show setation and spination. This is an exception, since most of the specimen is an internal mould of calcium carbonate. [1] The specimen was labeled with the number MB.A 2966, and deposited in the Museum für Naturkunde, Berlin, being named in 2014 by Paul A. Selden & Jason A. Dunlop Seppo koponeni, after the Finnish arachnologist Seppo Koponen , to celebrate his 70th birthday. [1] [4]
The genus was described as the oldest Palpimanoidea or the nearest sister taxon to the group. [5] The exact familiar placement of the genus is unclear, as it was assigned to the family based on the presence of peg teeth, a synapomorphy thought to be unique to the superfamily. [5] However, recent revisions of modern spiders have shown that this character is also present in the Mimetidae and other Entelegynae families. [5] Early araneomorphs such as those in the clade Synspermiata and the families Filistatidae, Austrochilidae and Leptonetidae lack it, locating the genus as either a stem Palpimanoidea or a stem Entelegynae. [5]
Seppo koponeni is one of the only two arachnids ever to have been found in the Toarcian rocks of north Germany, outnumbered by several thousand insect specimens at several localities. [6] [1] The different between the number of insects as opposed to arachnids has not been studied in depth. A possibility is that because insects can fly over water, they fall into it far more easily than spiders. [1] It is unclear how the spider ended on a marine clay deposit, far from the land, although several theories have been suggested: ballooning is a possibility as a method of transport, perhaps helped by severe storms, hurricanes, and tornadoes. [1] Another possibility might be that it was carried out to sea on floating vegetation, as wood remains have been recovered in the deposit. [1]
On nearby land, ground dwellers were represented by arachnids, such as Seppo and scorpions, but also by Gryllidae, such as Protogryllus dobbertinensis , grylloblattodeans such as Nele jurassica , and dermapterans. [2] These arthropods never moved far from where they lived and are generally very rare in the rocks. [2] Seppo shows a rather unusual morphology, with large and porrect chelicerae and a robust leg I, contrasted with a short leg III. [1] The robust and well-armed first legs, directed forwards, give the impression that they were prey capture appendages, a morphology typical of a sit-and-wait predator, while the short third legs are more typical of web spiders, especially orbweavers, but also palpimanoids. Short third legs are not usually found on spiders that are substrate dwellers, which have more equal legs. [1] Seppo was probably not a habitual ground dweller. The armoured front legs related to capturing dangerous prey are typical of many extant palpimanoids that are araneophagous. [1]
The Trachypachidae are a family of beetles that generally resemble small ground beetles, but that are distinguished by the large coxae of their rearmost legs. There are only six known extant species in the family, with four species of Trachypachus found in northern Eurasia and northern North America, and two species of Systolosoma in Chile and Argentina. They were much more diverse in the past, with dozens of described species from the Mesozoic.
Mantispidae, known commonly as mantidflies, mantispids, mantid lacewings, mantisflies or mantis-flies, is a family of small to moderate-sized insects in the order Neuroptera. There are many genera with around 400 species worldwide, especially in the tropics and subtropics. Only five species of Mantispa occur in Europe. As their names suggest, members of the group possess raptorial forelimbs similar to those of the praying mantis, a case of convergent evolution.
Emausaurus is a genus of thyreophoran or armored dinosaur from the Early Jurassic. Its fossils have been found in Mecklenburg-Vorpommern, northern Germany. Emausaurus is the only known Toarcian thyreophoran, as well as the only dinosaur from the zone of the same age with a formal name.
Ohmdenosaurus is a genus of sauropod dinosaur that lived during the Early Jurassic epoch in what is now Germany. The only specimen – a tibia (shinbone) and ankle – was discovered in rocks of the Posidonia Shale near the village of Ohmden. The specimen, which was originally identified as a plesiosaur, is exhibited in a local museum, the Urweltmuseum Hauff. In the 1970s, it caught the attention of German palaeontologist Rupert Wild, who recognised it as the remains of a sauropod. Wild named Ohmdenosaurus in a 1978 publication; the only known species is Ohmdenosaurus liasicus.
Huttoniidae is a family of ecribellate araneomorph spiders containing a single genus, Huttonia, itself containing a single described species, Huttonia palpimanoides. It is known only from New Zealand.
The evolution of spiders has been ongoing for at least 380 million years. The group's origins lie within an arachnid sub-group defined by the presence of book lungs ; the arachnids as a whole evolved from aquatic chelicerate ancestors. More than 45,000 extant species have been described, organised taxonomically in 3,958 genera and 114 families. There may be more than 120,000 species. Fossil diversity rates make up a larger proportion than extant diversity would suggest with 1,593 arachnid species described out of 1,952 recognized chelicerates. Both extant and fossil species are described annually by researchers in the field. Major developments in spider evolution include the development of spinnerets and silk secretion.
Megarachne is a genus of eurypterid, an extinct group of aquatic arthropods. Fossils of Megarachne have been discovered in deposits of Late Carboniferous age, from the Gzhelian stage, in the Bajo de Véliz Formation of San Luis, Argentina. The fossils of the single and type species M. servinei have been recovered from deposits that had once been a freshwater environment. The generic name, composed of the Ancient Greek μέγας (megas) meaning "great" and Ancient Greek ἀράχνη (arachne) meaning "spider", translates to "great spider", because the fossil was misidentified as a large prehistoric spider.
Eoplectreurys is an extinct monotypic genus of spider from the family Plectreuridae, with a sole species, Eoplectreurys gertschi. The fossils of Eoplectreurys were recovered from the ~164 Ma old Middle Jurassic Daohugou formation tuffs in Inner Mongolia, China.
This glossary describes the terms used in formal descriptions of spiders; where applicable these terms are used in describing other arachnids.
Mongolarachne is an extinct genus of spiders placed in the monogeneric family Mongolarachnidae. The genus contains only one species, Mongolarachne jurassica, described in 2013, which is presently the largest fossilized spider on record. The type species was originally described as Nephila jurassica and placed in the living genus Nephila which contains the golden silk orb-weavers.
Termitaradus protera is an extinct species of termite bug in the family Termitaphididae known from several Late Oligocene to Early Miocene fossils found in Mexico. T. protera is the only species in the extant genus Termitaradus to have been described from fossils found in Mexican amber and is one of four species from new world amber; the others are Termitaradus avitinquilinus, Termitaradus dominicanus and Termitaradus mitnicki. T. protera was also the first termite bug described from the fossil record.
This list of fossil arthropods described in 2011 is a list of new taxa of trilobites, fossil insects, crustaceans, arachnids and other fossil arthropods of every kind that have been described during the year 2011. The list only includes taxa at the level of genus or species.
Uroballus koponeni is a species of spider of the genus Uroballus. It is endemic to the Malaysian part of Borneo.
Bajanzhargalanidae is an extinct family of winged polyneopteran insects, recorded from the Permian and Jurassic but not the Triassic. They are considered poorly known members of the "Grylloblattida", a poorly defined group of extinct insects thought to be related to modern ice crawlers (Grylloblattidae). There are at least four genera and about seven described species in Bajanzhargalanidae.
Liassoscorpionides is an extinct genus of scorpions from the Toarcian of Germany. It was found on the Posidonia Shale, on the so-called Mergelgrube “insect bed” of Hondelage near Braunschweig, on a layer, as it´s name suggests, full of insect genera. Liassoscorpionides is the only confirmed jurassic scorpion discovered. Liassoscorpionides represented a relatively small genus with a morphology resembing the extant genus Hadogenes.
The Sachrang Formation or "Posidonienschiefer" Formation is a geological formation of southwestern Germany, northern Switzerland, northwestern Austria, southeast Luxembourg and the Netherlands, that spans about 3 million years during the Early Jurassic period. It is known for its detailed fossils, especially sea fauna, listed below. Composed mostly by black shale, the formation is a Lagerstätte, where fossils show exceptional preservation, with a thickness that varies from about 1 m to about 40 m on the Rhine level, being on the main quarry at Holzmaden between 5 and 14 m. Some of the preserved material has been transformed into fossil hydrocarbon Jet, specially wood remains, used for jewelry. The exceptional preservation seen on the Posidonia Shale has been studied since the late 1800s, finding that a cocktail of chemical and environmental factors let to such an impressive conservation of the marine fauna. The most common theory is the changes in the oxygen level, where the different anoxic events of the Toarcian left oxygen-depleted bottom waters, with the biota dying and falling to the bottom without any predator able to eat the dead bodies.
The Ciechocinek Formation, known in Germany as the Green Series is a Jurassic geologic formation that extends across the Baltic coast, from Grimmen, Germany, to Lithuania, with its major sequence in Poland and a few boreholes in Kaliningrad. It represents the largest continental area defined as deltaic in the fossil record, estimated to cover ~7.1 × 100,000 km2 (39,000 sq mi) only in the Polish realm. It is mostly known by its diverse entomofauna, composed of more than 150 species of different groups of insects, as well its marine vertebrate fossils, including remains of sharks, actinopterygians and marine reptiles, along terrestrial remains of dinosaurs, including the early thyreophoran Emausaurus and others not yet assigned to a definite genus. Its exposures are mostly derived from active clay mining of a dislocated glacial raft with exposed Upper Pliensbachian to late Toarcian shallow-marine sediments. Starting with coarse and fine sand deposits with concretions, the pure clay of the Ciechocinek Formation, after the falciferum zone, was deposited in a restricted basin south of the Fennoscandian mainland. It hosts a layer full of carbonate concretions, where a great entomofauna is recovered.
The Ciechocinek Formation is a Jurassic geologic formation which extends across the Baltic coast from Grimmen, Germany, to Nida, Lithuania, with its major sequence in Poland and boreholes in Kaliningrad. Dinosaur species uncovered here, including Emausaurus and other unclassified genus.
Permopsocida is an extinct order of insects known from the Early Permian to the Mid-Cretaceous. It is part of Paraneoptera, alongside bark lice, bugs and thrips. Within Paraneoptera it is considered to be closer to the clade containing bugs and thrips rather than bark lice, with an estimated divergence during the Late Carboniferous. The group was first named as a suborder by Robert John Tillyard in 1926, and was raised to a full order by Huang et al. in 2016. It is currently divided up into three families, Psocidiidae which is known from the Permian to Liassic. Permopsocidae which is only known from the Permian, and Archipsyllidae, which is known from the Late Triassic to mid-Cretaceous (Cenomanian). While most members of the group are known from compression fossils, several members of Archipsyllidae are 3 dimensionally preserved in Burmese amber, which has helped clarify the morphology and phylogenetic position of the group. The morphology of the mouthparts suggests that they were capable of suction feeding and chewing, with preserved angiosperm pollen grains in the gut of Psocorrhyncha suggesting that at least some members of the group were pollenivorous.
Liadopsyllidae is an extinct family of hemipteran insects belonging to Psylloidea ranging from the Early Jurassic to Upper Cretaceous. The family was named by Andrey Vasilyevich Martynov in 1926. They are the earliest known members of Psylloidea, with modern members of the group not known until the Paleogene, as such, they have been suggested to be a paraphyletic assemblage ancestral to modern psylloids. The family Malmopsyllidae has been subsumed into this family, but is considered distinct by some authors.