Vision plays aparamount role in some spider families suchas the Salticidae, Lycosidae and Thomisidae, as it is involved in preyhunting, orientation or choice of substrate. Inthethomisid Misumenavatia, for which the substratecolour affectsthe body colour, vision seems to mediate morphological colour changes. However, nothing is known about which component of visual signals from the substrate might be perceived, norwhether M. vatia possesses the physiological basis for colourvision.Theaim of this study is thustoinvestigatethe vision of this spider species by measuring the spectralsensitivities of the different pairs ofe yes usingelectrophysiologicalmethods.Extra-and intracellularelectrophysiological recordings combined with selective adaptation revealed the presence oft woclasses of photoreceptor cells, one sensitive in the UV region of the spectrum (around340nm) and one sensitive in the green (around 520nm) regions in the four pairsofeyes. We concludethat M. vatia possesses the physiological potential to perceiveboth chromatic and achromatic components of the environment.