Early life history of aquariumheld blind well goby Luciogobius pallidus, collected from Wakayama Prefecture, Japan

Abstract

The blind well goby Luciogobius pallidus lives primarily in groundwater or spring in the western part of Honshu Island, Japan. Morphological changes and salinity tolerance of L. pallidus are described from artificially-reared eggs, lar-vae and juveniles. Aquarium-held L. pallidus spawned eggs (long axis 2.2 mm, short axis 0.7 mm) on 24 November 2003 (n=408) and 24 February 2004 (n=426), such being guarded in the nest by males. Newly-hatched larvae (3.0 mm notochord length) had small yolks and many melanophores on the snout to caudal region. Seventeen days after hatching (4.9 mm standard length), the notochord tip projected upwards, and dorsal and anal fin rays appeared. After 30 (8.5 mm standard length) to 45 days (11.7 mm standard length), the larvae settled to the bottom. Larvae and juveniles were able to survive in salinities of 10-20 psu, but quickly succumbed in higher salinities (25-35 psu), such intolerance being a likely factor limiting the spread of L. pallidus to off shore and more distant areas.