Yunnanilus nigromaculatus (Regan 1904)

 

Marco Endruweit, October 2006

Therefore Yunnanilus nigromaculatus possesses the status EN at the IUCN Red List for the criteria B1+2abc. This means this species is endangered (EN) due to a decline in its habitat and/or a rather limited occurrence.

It is said, nowadays Yunnanilus nigromaculatus is only known from Dianchi Lake in the Chinese Yunnan Province. The Dianchi Lake is located southern of the province’s capital Kunming. In the lake they are mainly feeding upon a small native shrimp species - Caridina gregoriana. The shrimp Macrobrachium nipponense was introduced into the lake. The agressive and stronger new alien species outcompeted the smaller C. gregoriana. The shortage in the base food resulted in a tremendously declining population of Yunnanilus nigromaculatus (Kottelat & Whitten, 1996).

The preserved specimen (numbered 58-1429) shown on the pictures out of the Shanghai Fisheries University collection has been gathered in 1958 in the Fuxian Lake, not in Dianchi Lake. The Fuxian Lake is located south eastern of the Dianchi Lake. It might be that Yunnanilus nigromaculatus has now been extinct in the Fuxian Lake.