Haikouichthys

Live reconstruction

• Chengjiang Faunengemeinschaft (China)

Haikouichthys ( Gr.: " fish of Haikou ") is a genus of the core group of vertebrates ( Vertebrata ). The only way is described Haikouichtys ercaicunensis from the Lower Cambrian of China. In the Konservatlagerstätte of Chengjiang far more than 500 individual fossils of the genus have been recovered.

Features

Haikouichtys was about 25 mm long, was slender, fish and streamlined. The fossils can be at the head eyes, small paired nasal cavities and in the first third of the body recognize six gill arches. In addition, a brain that is protected by cartilage. On a notochord, there are up to ten quadratic elements, which are possibly is cartilaginous vertebrae., The heart, the intestines and the gonads are visible. In the rear half of the body can be seen, V-shaped muscle packets. The body ends with a rounded tail fin.

System

Because of the gill basket, an annular lip cartilage and a single, upward-opening Nasenhypophysengangs one assumes that Haikouichthys is the sister species of lampreys ( Petromyzontiformes ) or the lampreys and the more advanced vertebrates. You may Haikouichthys is identical to Myllokunmingia. In this case Haikouichthys would become a junior synonym of Myllokunmingia. D.-G. Shu of the University of Northwest China, Xi'an which considers it unlikely.