Abstract

The parental care of the nests and the embryonic and larval development of the labrisomid blenny Labrisomus philippii (Teleostei: Labrisomidae) were described for the first time. In situ underwater recordings were done on nests deposited at 2-m depth at Pisagua and Sarmenia, northern Chile. The nests were composed by a mass of adhered eggs, exclusively on red algae covers (Rhodophyta) outside the crevices used by the adult and guarded by the male. Males utilized similar to 90% of the time taking care of the nest, defending it from predators (other fish and crustaceans), and keeping it clean. For the observation of larvae, egg masses were extracted from the nests and incubated in the laboratory. Eggs are spheroid, 1.09-1.23mm in size, with filaments originating from a central thallus in the basal pole, small perivitelline space and granular yolk, with numerous small oil droplets. Larvae hatched at an average size of 5.06 +/- 0.10mm body length (BL), with a functional mouth, and a round yolk-sac of 0.09 mm(3). Larvae are elongated, slightly laterally compressed, with a round and moderate head and a short snout. They have preopercular spines and 35 myomeres; melanophores are located on the cleithrum symphysis, over the head, along the base of the anal fin, between pterygiophores of the dorsal ray fin, and in the ventral margin of the gut. During development, larvae grew at 0.28 mm d(-1). Finally, this research helped to increase knowledge on early-life history traits of this coastal fish inhabiting rocky shores along the south Pacific Ocean.