Kyphosichthys

The holotype of Kyphosichthys grandei

• Guanling Formation in Luoping (eastern Yunnan (China) )

Kyphosichthys grandei is an extinct, primitive bony fish, whose fossil remains, a nearly complete holotype and para-type in the Guanling Formation in the eastern Chinese province of Yunnan were found. They were using index fossils from the group of conodonts on the Anisian dated a chronostratigraphic stage of the Middle Triassic.

The genus name is derived from " kyphos " and " ichthys " ( Gr.: bent and fish) together and makes reference to the curved topline, the epithet grandei was awarded in honor of the American biologists and paleontologists Lance Grande, which make a valuable contribution has brought to the study of Ginglymodi and recently revalidated the Knochenganoiden ( Holostei ).

Features

The holotype of Kyphosichthys grandei has a total length of 9.6, a standard length of 7.6 and a body height of 5.5 cm. He is so beside Dapedium and Felberia only the third known to date hochrückige fish among the primitive Neopterygiern. The body height is above 70 % of the standard length. Immediately behind the head, in front of the dorsal fin, the back profile runs in a large hump. The largest body height is achieved at the level of the posterior edge of gill cover.

Dorsal fin and anal fin are far behind, the latter is only half as long as the dorsal fin. The pelvic fins are much smaller than the pectoral fins. The forked caudal fin is heterocercal but outwardly almost symmetrical. Its upper lobe is beschuppt over a length of more than a third, this is supported by ten of the 23 fin rays.

• Fins formula: dorsal fin I/13; Anal fin i / 6; Pectoral fin 8; Ventral fin 6; Caudal fin 23
• Dandruff formula: SL 29

Way of life

Kyphosichthys grandei lived in the sea. From the comparison of species with recent high-backed marine fish, such as the Eberfischen or the butterfly fish, one can conclude that Kyphosichthys grandei slowly swam but was very agile and seemed well in a highly structured environment, such as rocky or coral reefs or in overgrown by kelp regions.

System

Kyphosichthys grandei is assigned to the Knochenganoiden ( Holostei ) and are part of there to the subgroup of Ginglymodi which includes the recent gars ( Lepisosteidae ). Together with the Semionotiformes and billfish -like ( Lepisosteiformes ) forms Kyphosichthys grandei a trichotomy facing the Macrosemiiformes as a sister group.

Source

• Guanghui Xu, FEIXIANG Wu: A deep- bodied fish from the Middle Triassic ginglymodian of eastern Yunnan Province, China, and the phylogeny of lower neopterygians. In: Chinese Science Bulletin. Vol 57, No. 1, January 2012, ISSN 0250-7862, pp. 111-118, doi: 10.1007/s11434-011-4719-1.

Itemization

• Bonefish
• Osteichthyes
• Extinct teleost