Photosynthesis and Bio-Optical Properties of Fluorescent Mesophotic Corals

Mesophotic coral ecosystems (MCEs) are light-dependent coral-associated communities found at 30–150 m depth. Corals inhabiting these deeper reefs often acclimatized to a limited and blue-shifted light environment, enabling them maintain the relationship with their photosynthetic algal symbionts (family Symbiodiniaceae) despite seemingly suboptimal conditions. Among others, fluorescent proteins produced by host may play role in modulation of quality spectral distribution irradiance within tissue through wavelength transformation. Here we examined bio-optical properties performances different fluorescence morphs two mesophotic species Goniopora minor Alveopora ocellata , order test photosynthesis enhancement hypothesis proposed for fluorescence. The green morph G. low A. exhibit, natural habitats, higher abundance. also presented reflectance attenuation tissue. Nevertheless, chlorophyll fluorescence-based, O 2 evolution measurements, revealed only differences between abilities three . did not differ densities or concentrations all corals harbored Symbiodiniaceae from genus Cladocopium Thus, change internal quantity that experience, no evidence facilitation