Yohoia

Yohoia
	Yohoia
Temporal occurrence
	middle Cambrian
Locations
	North America ( Burgess Slate , Canada );
Systematics
without rank:	Bilateria
	Primordial mouths (protostomia)
Over trunk :	Molting animals (Ecdysozoa)
Trunk :	Arthropod (arthropoda)
Family :	Yohoiidae
Genre :	Yohoia
Scientific name
	Yohoia
	Walcott , 1912
species
	Yohoia tenius;

Yohoia is an extinct species of animals from the early Cambrian . Fossils of its only known representative, Yohoia tenius , were discovered in the Burgess Shale in the eponymous Yoho National Park in the Canadian province of British Columbia and werefirst described scientifically in1912 by the American paleontologist Charles Walcott . Due to the more than 700 fossils of Yohoia tenius that have now been found, the genus is one of the more common representatives ofthe Burgess slate biota . Based on its anatomical features, Yohoia is believed to be an early descendant of the arachnid and crustacean lines .

features

Yohoia tenius was 7 to 21 mm in length. His body, consisting of 12 trunk segments and a head segment, was protected by an exoskeleton . The hull was closed by a paddle-shaped telson , which was supposed to be used for movement in the water. The trunk segments carried paddle-shaped extremities, which were also intended to be used for locomotion. The head segment, on the other hand, carried three pairs of leg-like extremities, which presumably provided support on the sandy seabed. Striking the pair of so-called was Great Appendages ( "large attachments") at the top. These great appendages had claws and were similar to those of Jianfengia , Alalcomenaeus, and Leancholia . They were probably used to catch prey.

Systematics

The systematic classification of Yohoia is considered problematic and is therefore discussed controversially. Based on the anatomy of the so-called Great Appendages, Yohoia probably represents, together with other representatives of the Megacheira group, an early descendant of the arachnid and crustacean lineage.

Individual evidence

↑ Chen J, Waloszek D, Maas A: A new “great appendage” arthropod from the Lower Cambrian of China and homology of chelicerate chelicerae and raptorial antero − ventral appendages . In: Lethaia . 37, 2004, pp. 3-20.

Web links

Commons : Yohoia - collection of pictures, videos and audio files

Yohaia on the Burgess Shale Geoscience Foundation website ( memento from October 23, 2010 in the Internet Archive )

[1] Chen J, Waloszek D, Maas A: A new “great appendage” arthropod from the Lower Cambrian of China and homology of chelicerate chelicerae and raptorial antero − ventral appendages . In: Lethaia . 37, 2004, pp. 3-20.