Gerard Lopes Belmonte, 23, was found guilty of second-degree murder in September and sentenced to life in prison on Wednesday, the South Florida Sun Sentinel reported.
Prosecutors said in the early hours of July 17, 2011, Lopes raped and killed Natalie Belmonte, 43, who is Lopes' cousin, but also adopted him after the defendant's father died in their native Guyana.
Belmonte's body was found three days later in a wooded area less than a mile from her home.
"The thing I found the most alarming, was the total lack of human compassion and no feelings of remorse by Mr. Lopes," said presiding Broward Circuit Judge Matthew Destry. "You dump her naked body in a swamp and you don't even have the decency to cover her up."
Friends and family said they were happy with the sentence.
"It has been a nightmare for our family," said Alex Teixeira, Belmonte's brother-in-law. "There are no words to express the depth of our sorrow over the loss of Natalie."
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