Keystone Species Conservation Act of 1999

Keystone Species Conservation Act of 1999 - Defines a "keystone species" as a species of fish or wildlife (excluding African and Asian elephants, rhinoceros, and tigers) that is listed as an endangered or threatened species under the Endangered Species Act of 1973 or Appendices I, II, or III of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES).

Directs the Secretary of the Interior, subject to the availability of funds, to use amounts in the Keystone Species Conservation Account established by this Act to provide financial assistance for projects for the conservation of keystone species throughout the world for which project proposals are approved by the Secretary. Permits proposals for projects for the conservation of a keystone species to be submitted to the Secretary by: (1) a country's wildlife management authority that has within its boundaries any part of the range of a keystone species, if the agency has authority over fish or wildlife and the agency's activities affect the species; (2) the CITES Secretariat; or (3) any person with demonstrated expertise in the conservation of such species.

Gives priority in funding to projects that: (1) will enhance programs for the conservation of keystone species that are most imperiled and are supported by a country's wildlife management authority in each country in which the program will be conducted; (2) receive the greatest level of non-Federal matching assistance; and (3) will enhance local capacity for the conservation of such species.

Establishes the Keystone Species Conservation Account in the Multinational Species Conservation Fund of the Treasury.

Authorizes appropriations.