''Palaeothele'' is an extinct

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

of mesothele

spider Spiders ( order Araneae) are air-breathing arthropods that have eight legs, chelicerae with fangs generally able to inject venom, and spinnerets that extrude silk. They are the largest order of arachnids and rank seventh in total species ...

s, with only one known species ''Palaeothele montceauensis''. Two

fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

s were found at

Montceau-les-Mines Montceau-les-Mines () is a commune in the Saône-et-Loire department in the region of Bourgogne-Franche-Comté in eastern France. It is the second-largest commune of the metropolitan Communauté urbaine Creusot Montceau, which lies southwest of ...

, France, in

ironstone Ironstone is a sedimentary rock, either deposited directly as a ferruginous sediment or created by chemical replacement, that contains a substantial proportion of an iron ore compound from which iron (Fe) can be smelted commercially. Not to be con ...

concretion deposits of

Late Carboniferous Late may refer to: * LATE, an acronym which could stand for: ** Limbic-predominant age-related TDP-43 encephalopathy, a proposed form of dementia ** Local-authority trading enterprise, a New Zealand business law ** Local average treatment effect, ...

( Stephanian) age, about .

Taxonomy

The genus was first named as ''Eothele'' by Paul A. Selden in 1996. However, this name had already been used for a Cambrian

brachiopod Brachiopods (), phylum Brachiopoda, are a phylum of trochozoan animals that have hard "valves" (shells) on the upper and lower surfaces, unlike the left and right arrangement in bivalve molluscs. Brachiopod valves are hinged at the rear end, w ...

, so in 2000, Selden proposed the replacement name ''Palaeothele''. ''Palaeothele'' is derived from the

Greek Greek may refer to: Greece 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 ...

, "ancient", and , "nipple" – a common ending for spider names, referring to their

spinnerets A spinneret is a silk-spinning organ of a spider or the larva of an insect. Some adult insects also have spinnerets, such as those borne on the forelegs of Embioptera. Spinnerets are usually on the underside of a spider's opisthosoma, and are ...

. The species name ''montceauensis'' refers to the location where the fossils were found.

Phylogeny

In 1996, Selden suggested the relationships shown in the cladogram below. (At the time, ''

Attercopus ''Attercopus'' is an extinct genus of arachnids, containing one species ''Attercopus fimbriunguis'', known from flattened cuticle fossils from the Panther Mountain Formation in Upstate New York. It is placed in the extinct order Uraraneida, sp ...

'' was thought to be a spider; it is now considered to belong to a related but separate group, the

Uraraneida Uraraneida is an extinct order of arachnids, known from fossils of Middle Devonian, Permian and possibly Cretaceous age. Two genera of fossils have been definitively placed in this order: ''Attercopus'' from the Devonian of United States and '' ...

.) ''Palaeothele'' is shown as sister to the modern genus ''

Heptathela ''Heptathela'' is a genus of spiders that includes the Kimura spider (''Heptathela kimurai''). They are trapdoor spiders of the family Liphistiidae and are found in Japan, including Okinawa and the Ryukyu Islands. Spiders of this genus lack veno ...

'' since they both have "tracheal sacs", structures adjacent to the posterior

book lungs A book lung is a type of respiration organ used for atmospheric gas exchange that is present in many arachnids, such as scorpions and spiders. Each of these organs is located inside an open ventral abdominal, air-filled cavity (atrium) and con ...

References

Mesothelae Paleozoic arachnids Carboniferous animals of Europe {{paleo-spider-stub