Nazi war criminal Josef Mengele hid in Brazil from 1961 until his death in 1979 and so could not have spent more than two years in Paraguay, according to new testimony by one of the couples who claim to have sheltered him here.

Federal police today released the transcript of testimony given last night by Gitta Stammer, a 65-year-old woman of Hungarian descent who said she and her husband sheltered Mengele on three small farms in the Sao Paulo area, before passing him on to the Austrian couple Wolfram and Liselotte Bossert, who are the principal witnesses to Mengele's presence in Brazil, and his supposed death in 1979.

The testimony conflicts with much of the postwar history of Mengele's activities compiled by Nazi hunters.

Stammer's account to police, which corroborated some details provided earlier by the Bosserts, marked the latest development in the search for Mengele.

The search took on fresh impetus with the May 31 discovery by West German police of letters leading to a grave exhumed Thursday containing remains Brazilian police believe may be those of Mengele.

Stammer's testimony led Sao Paulo's federal police chief, Romeu Tuma, to say today that "the evidence is too convincing" that Mengele lived here.

Stammer testified to police yesterday that in 1961 the couple was introduced to a Swiss citizen known as Peter Hochbichlet, who came to work for them on their farm initially without pay. By 1962 the man had revealed his true identity, Mengele.

He was introduced to the Stammers by Wolfgang Gerhard, an Austrian whose identity she said Mengele later assumed. Mrs. Stammer said Gerhard threatened the couple to stay silent.

She said that Mengele, whom she called an authoritarian and irascible farm manager who bullied employes and interfered in their family life, made three successive moves with them to small farms close to Sao Paulo, while relations deteriorated steadily. During this time he scarcely left the property.

When the Stammers threatened to eject Mengele, they received two conciliatory visits from a man called Hans, who she said came from the Mengele equipment factory in West Germany.

She told police that Hans regularly brought large supplies of dollars, but she did not testify if this man was Hans Sedlmeier, the former Mengele company employe in Guenzburg, in whose home police found addresses that led them to Brazil.

Stammer said that in 1969 Mengele first brought Wolfram Bossert to the farm, and thereafter Bossert, who worked at a nearby factory, would visit regularly and take Mengele to stay for the night at his house.

In February 1975, the Stammers, who owned a house at Estrada do Alvarenda, where Mengele was to be housed, passed him on to the Bosserts. Later, the Bosserts became owners of the house, and the Stammers hardly saw him again.

Stammer said in her testimony to police that after he was confronted with published photographs and his identity uncovered, Mengele revealed that he had been at Auschwitz, where he had caught typhoid. He avoided talking about the war.

Stammer said that one of his few pleasures was listening to Mozart and that he was an intelligent, cultivated man. Police have recovered a textbook on anthropology and a paper Mengele was writing. Mengele told her that soon after World War II he had fled to Italy, and then on a French ship to Buenos Aires. Afterward he lived near Asuncion, Paraguay, and came to Brazil around 1961. He also had spent a short time in Uruguay.

She said he had contracted a tropical disease in Paraguay that caused cramps and swelling of one leg. He also had rheumatism and suffered from headaches.

Stammer confirmed the account of Mengele's death by drowning Feb. 7, 1979, at Bertioga, and said that Liselotte Bossert had taken care of funeral arrangements.

She identified Mengele both from portrait photographs taken by Bossert and from false identity documents in the name of Wolfgang Gerhard.

The testimony, which supports many details given by the Bosserts, led police chief Tuma to say he was now certain that Mengele had indeed lived for years in Sao Paulo, whether or not he had been buried at Embu, near Sao Paulo, where the body was exhumed Thursday.

The evidence so far points to a lengthy stay by Mengele in Brazil, and it would appear to reduce the time he spent in Paraguay to between 1959, when he applied for citizenship there, and 1961. This contradicts much of the history compiled by Nazi hunters.

Experts from the Medical Legal Institute expected to take until the end of the month to complete forensic tests and have turned down offers of help from the United States, West Germany and Israel. Officials of these governments will be allowed only to observe the process.

Analysis depends largely upon comparing dental evidence with records dating from 1937. At Thursday's exhumation, coroner Jose Antonio de Mello found seven remaining teeth and two dental bridges or plates, probably the recent work of a Brazilian dentist.