''Electrocteniza'' is an

extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispec ...

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

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 ...

in the family

Ctenizidae Ctenizidae is a small family of mygalomorph spiders that construct burrows with a cork-like trapdoor made of soil, vegetation, and silk. They may be called trapdoor spiders, as are other, similar species, such as those of the families Liphistii ...

. At present, it contains the single species ''Electrocteniza sadilenkoi''. The genus is solely known from the

Early Eocene In the geologic timescale the Ypresian is the oldest age or lowest stratigraphic stage of the Eocene. It spans the time between , is preceded by the Thanetian Age (part of the Paleocene) and is followed by the Eocene Lutetian Age. The Ypresian i ...

Baltic amber 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 1 ...

deposits in the

Baltic Sea The Baltic Sea is an arm of the Atlantic Ocean that is enclosed by Denmark, Estonia, Finland, Germany, Latvia, Lithuania, Poland, Russia, Sweden and the North and Central European Plain. The sea stretches from 53°N to 66°N latitude and from ...

region of Europe.

History and classification

''Electrocteniza sadilenkoi'' is known only from one fossil, the holotype, number "PIN, no. 363/88". It is a single male individual preserved in a clear amber specimen with several unidentified insects associated. The amber specimen was first identified as significant while residing in a private collection housed in

Moscow, Russia Moscow ( , American English, US chiefly ; rus, links=no, Москва, r=Moskva, p=mɐskˈva, a=Москва.ogg) is the Capital city, capital and List of cities and towns in Russia by population, largest city of Russia. The city stands on t ...

. The specimen was then donated to the Paleontological Institute of the Russian Academy of Science in Moscow. ''E. sadilenkoi'' was first studied by

Kirill Eskov Kirill Yuryevich Eskov (russian: Кири́лл Ю́рьевич Есько́в; born 16 September 1956) is a Russian writer, biologist and paleontologist. As an author he is known for '' The Gospel of Afranius'' in which he presents an atheistic ...

and Sergei Zonstein, with their 2000

type description A species description is a formal description of a newly discovered species, usually in the form of a scientific paper. Its purpose is to give a clear description of a new species of organism and explain how it differs from species that have be ...

being published in the Russian ''

Paleontological Journal ''Paleontological Journal'' (Russian: ''Paleontologicheskii Zhurnal'') is a monthly peer-reviewed Russian journal of paleontology established in 1959. It focuses on the paleontology and the fossil records of Eastern Europe and Asia. Articles are ...

''. The

generic Generic or generics may refer to: In business * Generic term, a common name used for a range or class of similar things not protected by trademark * Generic brand, a brand for a product that does not have an associated brand or trademark, other ...

name was coined by K. Eskov and S. Zonstein as a combination of the

Ancient Greek Ancient Greek includes the forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Dark Ages (), the Archaic peri ...

word ''electron'', meaning "amber", and ''

Cteniza ''Cteniza'' is a small genus of Old World trapdoor spiders found in France and Italy, first described by Pierre André Latreille Pierre André Latreille (; 29 November 1762 – 6 February 1833) was a French zoologist, specialising in arthro ...

'', the modern trapdoor spider genus for which the family was named. This is in reference preservation of the type specimen and the genus that ''Electrocteniza'' is possibly related. The specific epithet "''sadilenkoi''" was designated by K. Eskov and S. Zonstein in honor of the collector of the specimen, K. M. Sadilenko.

Description

''Electrocteniza sadilenkoi'' is in length when the chelicerae are included in the measurement. Of that length the

carapace A carapace is a Dorsum (biology), dorsal (upper) section of the exoskeleton or shell in a number of animal groups, including arthropods, such as crustaceans and arachnids, as well as vertebrates, such as turtles and tortoises. In turtles and tor ...

is and the

abdomen The abdomen (colloquially called the belly, tummy, midriff, tucky or stomach) is the part of the body between the thorax (chest) and pelvis, in humans and in other vertebrates. The abdomen is the front part of the abdominal segment of the torso. ...

is . The shape and general structure of the carapace indicates a close relationship to the modern genera '' Latouchia'' from Asia and '' Sterrochrotus'' from South Africa. There are several differences between the genera. In general, ''Electrocteniza's'' eye tubercle is raised higher than ''Latouchia'' and ''Sterrochrotus''. Unlike the modern genera of Ctenizidae, ''Electrocteniza'' has completely spineless tibiae, metatarsi and tarsi on legs I and II and chelicera which lack a rastellum.

References

{{Taxonbar, from=Q3050591 Ctenizidae Mygalomorphae genera Monotypic Mygalomorphae genera Prehistoric life of Europe Eocene arthropods Fossil taxa described in 2000 Baltic amber