Lumia, I am confused by your answer. First you say that
Samantha "is not used" in Spain, and then you say that there are 311 Samanthas and 249 Samantas in Catalonia. Isn't that a contradiction? Or are you claiming that though
Samantha is sometimes used in Catalonia it's not used in the rest of Spain? I would personally find it very odd if this name was ONLY found in Catalonia within Spain.
The name has certainly been used in Spanish-speaking countries in Latin
America. For example, there is any internationally famous squash player named
Samantha Teran from Mexico, born in Mexico City:
http://www.squashsite.co.uk/vintage/teran.htm