An explanation for the inter-species variability of the photoprotective non-photochemical chlorophyll fluorescence quenching in diatoms

► Diatom inter-species differences in non-photochemical quenching (NPQ) were assessed. ► New spectroscopic fingerprints (Δ522 nm, Chl a711) related to NPQ were found. ► They were successfully used for characterizing the NPQ inter-species differences. ► They demonstrate an additional regulatory feature of the NPQ in diatoms. ► This study strengthens the potential role of NPQ in the ecophysiology of diatoms.