The female titi monkey was 33 years old, which is almost three times the life expectancy.
Delasol had many geriatric health issues over the past eight years, according to the zoo.
As her health began to decline, veterinarians made the decision to euthanize Delasol.
"We've always said she is the queen of Primate House; it's her world and we're just living in it," a zoo spokesperson said.
Delasol enjoyed her heat lamp, tail twining with her family, pecans, and poplar leaves.
"We will miss her hands that we liked to say had 'Grinch fingers'," the zoo added.
Delasol had nine offsprings, and 22 grandkids.
"Delasol was and is so special to us, we will miss her deeply."
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