A number of Crypto-Jewish communities survive today, especially in
former Spanish-influenced regions, such as the southwestern U.S.A.
They still maintain extensive secrecy after centuries. Other
communities were lost to assimilation, but maintained residual Jewish
practices such as lighting candles Friday night. Cohen's The Marranos
and Prinz's The Secret Jews claim that the following are examples of
such communities, although such claims have not been verified and are
disputed by some:
* The Antiqueñas of Colombia.
* Much of Northern Mexico's middle and upper classes (Nuevo Leon is
the "New Lion of Judah"). Note: Some note that Neuvo Leon mean was
named after the old Leon in Spain. However, whatever the origin of
the name, many of the families of Monterrey, Nuevo Leon, have
managed to keep in their memory, after more than 400 years, their
Separdic origin.
* The Naucalpan and Vallejo districts of Mexico City. (Technically,
Naucalpan is not in the Distrito Federal, but in the greater
metropolitan area).
* The Chuetas of Majorca. A look at Chueta last names shows many
surnames which have became quite famous in the Hispanic world.
They include Mir, Miro, and Marti. Of course Joan Miro was
Mallorcan. Any marranism in Fidel Castro's family would be through
his mother, as his father's family was Gallego, and very few Jews
ever lived in Galicia (of course plenty lived in the Austrian
Galicia, I'm refering to northwestern Spain ). Interesting about
the mountains on the Spanish-Portuguese border being a hotbed of
marranism, particularly those on the Extremadura-Andalucia border.
This area is directly inland from some of the areas which
contained the earliest Jewish communities on the Iberian peninsula
- for example Huelva and Gibraltar. Malaga and Almunecar - which
also had early communities - are also in Andalucia. According to
Timothy Mitchell's book Flamenco: Deep Song and other sources, the
inquisition in western Andalucia was slightly more lenient than
elsewhere because of the need for labour related for the new world
trade and mining. The connections are quite interesting.

Famous Hispanics who have acknowledged Marrano ancestry include Rita
Moreno and Fidel Castro. Jews have played an important role in the
history of Monterrey, Mexico. Frida Kahlo's father, Guillermo Kahlo, a
somewhat reknowned photographer in his own right, was a Hungarian Jew.

http://www.faqs.org/faqs/judaism/FAQ/07-Jews-As-Nation/