Myllokunmingia
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The Myllokummingia is a primitive, probably agnathid (jawless) fish from the Lower Cambrian Maotianshan shales of China thought to be a chordate. It somewhat resembles hagfish, a modern agnathid. It is described as 28mm long and 6mm high.
The holotype was found in the Yuanshan member of the Qiongzhusi Formation in the 'Eoredlichia' Zone near Haikou at Ercaicun, Kunming City, Yunnan, China. The animal has a distinct head and trunk with a forward sail-like (1.5mm) dorsal fin and a ventral fin fold (probably paired) further back. The head has five or six gill pouches with hemibranchs. There are 25 segments (myomeres) with rear directed Vs in the trunk. There is a notochord, a pharynx and digestive tract that may run all the way to the rear tip of the animal. The mouth can not be clearly identified. There may be a pericardic cavity. There are no fin radials. There is only one specimen which has the tip of the tail buried in sediment. There is no sign of mineralization of the skeletal elements.
A similar creature from these shales is known as Haikouichthys. Suspected chordates (more primitive hemichordates) are also known from these deposits.
There is one species - Myllokummingia fengjiaoa (Shu, Zhang & Han).
External link
- See the following web site for more information and a picture: http://www.sciencenews.org/sn_arc99/11_6_99/fob1.htm