Ainiktozoon is an enigmatic fossil

Fossil

Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...

 genus from the Silurian

Silurian

The Silurian is a geologic period and system that extends from the end of the Ordovician Period, about 443.7 ± 1.5 Mya , to the beginning of the Devonian Period, about 416.0 ± 2.8 Mya . As with other geologic periods, the rock beds that define the period's start and end are well identified, but the...

 of Scotland

Scotland

Scotland is a country that is part of the United Kingdom. Occupying the northern third of the island of Great Britain, it shares a border with England to the south and is bounded by the North Sea to the east, the Atlantic Ocean to the north and west, and the North Channel and Irish Sea to the...

. Originally described as an early chordate

Chordate

Chordates are animals which are either vertebrates or one of several closely related invertebrates. They are united by having, for at least some period of their life cycle, a notochord, a hollow dorsal nerve cord, pharyngeal slits, an endostyle, and a post-anal tail...

, recent studies suggest that it was in fact an arthropod

Arthropod

An arthropod is an invertebrate animal having an exoskeleton , a segmented body, and jointed appendages. Arthropods are members of the phylum Arthropoda , and include the insects, arachnids, crustaceans, and others...

, more precisely a crustacean

Crustacean

Crustaceans form a very large group of arthropods, usually treated as a subphylum, which includes such familiar animals as crabs, lobsters, crayfish, shrimp, krill and barnacles. The 50,000 described species range in size from Stygotantulus stocki at , to the Japanese spider crab with a leg span...

 belonging to the little known extinct class Thylacocephala

Thylacocephala

The Thylacocephala are a unique group of extinct arthropods, with possible crustacean affinities. As a class they have a short research history, having been erected in the early 1980s. They typically possess a large, laterally flattened carapace that encompasses the entire body...

.

The only discovered species, Ainiktozoon loganense, is known from a number of specimens from Silurian rocks (Ludlow series) at Lesmahagow

Lesmahagow

Lesmahagow is a small town on the edge of moorland, near Lanark in the central belt of Scotland. It is also known as Abbey Green.-Etymology:The name is possibly a corruption of "Church of St Machutus"...

 in Scotland. Ainiktozoon is Greek

Greek language

Greek is an independent branch of the Indo-European family of languages. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. Its writing system has been the Greek alphabet for the majority of its history;...

for "enigmatic animal", from .

External links

• Images of Ainiktozoon (see the files whose names start "ain")