Nesting Behavior, Male Parental Care, and Embryonic Development in the Fairy Basslet, Gramma loreto

Demersal egg masses were recovered from nests attended by males of Gramma loreto, a species that has been reported to be a mouthbrooder. Nests consisted of small cylindrical holes, narrow crevices, or small depressions in hard substratum. Eggs were deposited on a loose clump of entangling algae that clung to the inside wall of the nest and formed a plain sheet of one to three layers of eggs. Males showed various types of nest care behavior. They hovered in front of or remained at their nest entrance and chased other fish species that approached their nest; constructed an algal mat at the nest entrance; carried pieces of algae into nest interior; and removed silt from the inside of the nest. There was no evidence to support the hypothesis that G. loreto is a mouthbrooder. Eggs collected from the field were reared in the laboratory at the temperature of 23-27 C and required about 10-11 days from morula stage to hatching. The newly hatched larvae had pigmented eyes, well-developed jaws, a small amount of yolk, and were 2.9-3.8 mm in total length.