Ontogenic phototactic behaviors of larval stages in intertidal barnacles

• Published in: Hydrobiologia Vol. 849; no. 3; pp. 747 - 761
• Main Authors: Kim, Hee-Jin, Araki, Takumi, Suematsu, Yumi, Satuito, Cyril Glenn
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01.02.2022; Springer; Springer Nature B.V
• Subjects: Adults; Behavior; Biomedical and Life Sciences; Coastal ecosystems; Compound eyes; Developmental stages; Ecology; Fisheries; Freshwater & Marine Ecology; Irradiation; Larvae; Larval development; Larval stage; Life Sciences; Light; Light effects; Light irradiation; Marine crustaceans; Photoreceptors; Phototaxis; Physiology; Primary Research Paper; Radiation; Wavelength; Wavelengths; Zoology; Settlement; Light wavelength; Light intensity; Phototaxis; Barnacle larvae
• ISSN: 0018-8158; 1573-5117
• DOI: 10.1007/s10750-021-04744-1

During larval development of the intertidal barnacle Fistulobalanus albicostatus , larvae in the naupliar stages I and II (NI&II) possess a single naupliar eye, and later develop additional pair of compound eyes in the naupliar VI (NVI) and cyprid stages. These eyes showed light wavelength-dependent absorbances; where the highest absorbance was within 550 to 600 nm. The phototaxis of each stage was determined under light irradiation at six wavelengths (375, 470, 515, 525, 660, and 735 nm) and at three intensities (5, 15, and 25 W/m 2 ), except for the 735 nm treatment which was irradiated at 25, 50, and 100 lx. NI&II larvae showed no clear pattern of phototaxis under the assessed light conditions. NVI and cyprids exhibited strong positive phototaxis under the assessed light conditions, except under 375 nm at 5 and 15 W/m 2 where negative phototaxis was detected. Furthermore, the settlement behavior of cyprids was examined under 375 nm at the three intensities, and under the other five wavelengths at 25 W/m 2 or 100 lx. The highest and lowest rates of settlement occurred at 470 and 375 nm, respectively. The results provide a valuable insight into the light-response mechanisms that potentially determine the distribution of barnacle larvae.