AUTHOR=Wang Shuhong , Wang Lin , Wang Yuyue , Chen Yun , Chen Jinmin , Chen Nan 

TITLE=Embryo Development and Effects of Temperature, Salinity, and Light Intensity on Egg Hatching of Calanoid Copepod Bestiolina amoyensis (Calanoida: Paracalanidae)

JOURNAL=Frontiers in Marine Science

VOLUME=Volume 9 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/marine-science/articles/10.3389/fmars.2022.940303

DOI=10.3389/fmars.2022.940303

ISSN=2296-7745

ABSTRACT=Bestiolina amoyensis distributes in subtropical inshore waters across the Pacific Ocean, with a relatively long reproductive lifespan and high intrinsic population increase rate, which make it a good candidate to develop culture techniques for hatchery larval rearing. While, the reproductive biology of this subtropical broadcast spawning species still largely unknown. The present investigation provides the first published data on the embryo development and effects of different light intensities (0 Lux, 500 Lux, and 1000 Lux), temperatures (16, 18, 20, 22, 24, 26, 28, 30, 32, and 34°C) and salinities (22, 24, 26, 28, 30, 32, and 34 psu) on hatching success rates of B. amoyensis. The same batch of eggs were collected from gravid females to observe their embryonic development, and incubated under designed light intensities, temperatures, and salinities. Results showed that the whole embryonic development of B. amoyensis lasted on average of 6 h 40 min at 26℃, and egg hatching time of B. amoyensis shortened exponentially with the increasing temperature. The highest egg hatching rate (100%) was recorded from the 0 Lux treatment, indicating dark condition was favorable for the egg incubation of B. amoyensis. The optimum temperature and salinity range for the hatching success of B. amoyensis was 22-30°C (above 94%), 22-34 psu salinity (above 88%) respectively, indicating B. amoyensis had wide adaptability to temperature and salinity. Light and too low or high temperature leads to abnormal embryonic development and malformed nauplii. The relatively wide adaptability to temperature and salinity and fast embryo development also suggests B. amoyensis was a good candidate as live feed for hatchery larval rearing.