No. 27: May-Jun 1983
The astounding item that follows is taken from the new journal Cryptozoology, which is the official journal of the International Society of Cryptozoology. The Society was founded by a group of scientists interested in unrecognized species of animals.
"An aquatic creature roughly resembling the traditional 'mermaid,' and sometimes identified with it, is reportedly known through a variety of encounters with natives of Central New Ireland. The ri, as they are called, are frequently sighted by fishermen, occasionally netted or found dead on beaches, and sometimes eaten. Males, females and juveniles are reported, subsisting on fish in the shallow seas around the Bismarck and Solomon archipelagos. It is unlikely that the animals are dugongs or porpoises, both of which are known to, and readily identified by, the natives."
New Ireland is northeast of Papua-New Guinea. The article proper goes on to describe the ri as an air-breathing mammal with human-like head, arms, genitalia, and upper trunk. The lower trunk is legless and terminates in a pair of lateral fins.
(Wagner, Roy; "The Ri -- Unidentified Aquatic Animals of New Ireland," Cryptozoology, 1:33, 1982.)
Reference. Unrecognized mammals are cataloged in Chapter BMU in Biological Anomalies: Mammals II. Ordering information can be found here.