''Pytine'' 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 n ...

of asaphid

trilobite Trilobites (; meaning "three lobes") are extinct marine arthropods that form the class Trilobita. Trilobites form one of the earliest-known groups of arthropods. The first appearance of trilobites in the fossil record defines the base of the ...

s. Species lived during the later part of the Arenig stage of the

Ordovician Period The Ordovician ( ) is a geologic period and system, the second of six periods of the Paleozoic Era. The Ordovician spans 41.6 million years from the end of the Cambrian Period million years ago (Mya) to the start of the Silurian Period Mya. T ...

, approximately 478 to 471 million years ago. Various species are found in the Svalbard, Valhallfonna Formation, Olenidsletta, Member, of Spitzbergen, Norway, the ''Megistaspis (Paramegistaspis) planilimbata'' Zone of the '''Shumardia'' Shale' of Sweden, Jujuy Province, Argentina, early Arenig-aged strata of Jiangxi province, China, and Darriwilian-aged strata in Western Hunan province, China. The type species, ''P. graia'', has seven thorax segments, and lacks the rapier-like glabellar spine, that occurs in many other raphiophorids. The Chinese species, by contrast, have only six thoracic segments. So far, only the type species, and one of the Chinese species, ''P. laevigata'' (synonym= ''Jiuxiella laevigata''), are known from complete specimens.

Species and synonymy

Richard Fortey erected the genus in 1975 upon describing ''P. graia'' from Spitzbergen. In 1999, Hoel subjectively synonymized a Swedish species of ''Ampyx'', ''A. brevicauda'', into ''Pytine''. The Chinese raphiophorid genera ''Jiuxiella'' and ''Miboshania'' were noted to be anatomically similar to ''P. graia'', and were merged into ''Pytine'', as well. In 2006, N. E. Vaccari described ''P. wirayasqa'' from several fragments from the early Arenig-aged Acoite Formation, of La Ciénaga, Jujuy province, Argentina, together with specimens of another related raphiophorid genus, '' Lehnertia''.

Etymology

''Pytine'' is derived from an

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 p ...

word for a wineflask with wattles, referring to the shape and wrinkled texture of the glabellum.

References

Raphiophoridae Asaphida genera Ordovician trilobites Fossils of Svalbard {{Svalbard-stub