Clue: Seaweed repeatedly gathered from prime locations in La Guaira (4-4)
Answer: AGAR-AGAR
Explanation: Definition: Seaweed
 **2nd, 3rd, 5th, and 7th letters of**(gathered from prime locations in/letters in the 1st 4 prime number positions) "La Guaira" **x 2**(repeatedly …)