Pytine

Pytine Temporal range: Early[1] to Late Arenig[2]
P. graia
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Trilobita
Order:	Asaphida
Suborder:	Trinucleina
Family:	Raphiophoridae
Subfamily:	Endymioniinae
Genus:	Pytine Fortey, 1975
Type species
Pytine graia
Species
P. graia Fortey, 1975 (type) P.? brevicauda (Wiman, 1905) P. corrugata Zhang & Zhou in Zhang, 1979 P. wirayasqa Vaccari, et al. 2006[1]
Synonyms
Ampyx brevicauda Wiman, 1905 Jiuxiella laevigata Liu in Zhou et al., 1977 Jiuxiella jiangxiensis Zhou et al., 2001 Miboshania corrugata Zhang & Zhou in Zhang, 1979

Pytine is an extinct genus of trilobites. It lived during the later part of the Arenig stage of the Ordovician Period,^[2] 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.^[3] The Chinese species, by contrast, have only six thoracic segments.^[1] So far, only the type species, and one of the Chinese species, P. laevigata (synonym= Jiuxiella laevigata), are known from complete specimens.^[1]

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

References

1. Vaccari, N. EMILIO, BEATRIZ G. Waisfeld, BRIAN DE Chatterton, and G. D. Edgecombe. "New raphiophorid trilobites from the Ordovician of Argentina and their biogeographic implications." MEMOIR-ASSOCIATION OF AUSTRALASIAN PALAEONTOLOGISTS 32 (2006): 353.
2. Sepkoski, Jack (2002). "A compendium of fossil marine animal genera (Trilobita entry)". Bulletins of American Paleontology 364: 560. Retrieved 2008-01-12.
3. Fortey, R.A. (1975). The Ordovician Trilobites of Spitsbergen [II. Asaphidae, Nileidae, Raphiophoridae and Telephinidae of the Valhallfonna Formation]. Norsk Polarinstitutt Skrifter 162. Oslo: Norsk Polarinstitutt.