Japanese otter
Museum copy of the Japanese otter
The Japanese otter ( Lutra nippon) is an extremely rare or already extinct species of Altweltotter within the marten, the species status is in doubt. He was historically common on the Japanese islands. In 1979, he was last spotted on the island of Shikoku.
Features
The Japanese otter corresponds in appearance to the Eurasian otter. The head -body length is in the range of about 90 centimeters and corresponds to the large individuals of the Asian subspecies of the Eurasian otter and is slightly larger. The tail is in proportion to the body significantly longer than in the Eurasian otter; at the Japanese otter it corresponds to 60 to 70% of the body length, the Eurasian otter only 53 to 60 %. Other differences relate to the shape of the Rhinalium. The coat consists of short hair, the body coloration is dark brown to gray- brown with light brown proportions. The belly is pale with white hair. The throat and the front neck are beige, the hair in the upper lip almost white
The species description was mainly based on the skull. This is powerfully built with a comparatively large facial skeleton. This differs in the position of individual window as the foramen ovale, and the proportions of individual cranial regions to each other by the Eurasian otter.
Distribution and conservation status
The Japanese otter was formerly thought to be widespread on the Japanese islands, but applies since the Meiji period in many parts of Japan as extinct. Between 1955 and 1959, he was last spotted on Honshu, Kyusyu and Hokkaido. The final proof evidence in 1979 on the island of Shikoku, as a dead specimen was found. A search for the species in the 1990s was inconclusive
Way of life
Over the life of the Japanese otter has no information. It can be assumed that they are from the Eurasian otter is not significantly different.
System
Status of the Japanese otter as an independent species is controversial. It was founded in 1989 by the Japanese zoologists Imaizumi and Yoshiyuki (1989 ) separated from the Eurasian otter and described as a separate species. For example, while Wozencraft in Wilson and Reeder (2005) follows this assumption in the IUCN species status is shown to be unsafe and the Japanese Otter described as a population of the Eurasian otter.
The separate species status in 1996 was supported by a molecular biological comparison of the mitochondrial gene for cytochrome b of Suzuki et al., In which a difference of 3.6 % of the observed nucleotides was detected. Since this difference is greater than that of the also considered species pair of fire weasel (Mustela sibirica ) and Japanese weasel (Mustela itatsi ) and higher than that specified in a study on the phylogeny of the raccoon minimum difference in the corresponding DNA sequence ( minimum 3.5 %), the species status for the Japanese otter was confirmed.