Author/Editor		Stušek, P; Hamdorf, K
Title		Properties of pupil mechanisms in owl-fly Ascalaphus macaronius (Neuroptera)
Type		članek
Source		J Comp Physiol (a)
Vol. and No.		Letnik 184
Publication year		1999
Volume		str. 99-106
Language		eng
Abstract		Regulation of light Hux by pupil mechanisms in the UV-sensitive superposition eye of owl-fly Ascalaphus macaronius (Neuroptera) was studied with a fast reflection microspectrophotometric technique. The spectral sensitivity of pupil reaction, which was calculated on the basis of changes of transient amplitude reftection, was almost identical with the one of Deilephila eye. This indicates that in spite of different life styles and spectral sensitivities of photoreceptors pupil closing is triggered by the same photosensitive structure in both eyes. By measuring the spectra of reftected light from the Ascalaphus eye between 400 and 700 nm after different dark periods following light stimulation, it was established that the restoration of reflection was much faster in the red than in the blue spectral range. Based on this, we propose that two different pupil mechanisms with different spectral absorption characteristics are involved in light-Hux regulation. Fast-reacting pupil is probably represented by screening pigment migration in the secondary pigment cells and a slow blue-absorbing system by the activity in primary pigment cells. The importance of two different pupils for the photoregeneration of visual pigment is discussed.
Descriptors		INSECTS PUPIL PIGMENT EPITHELIUM OF EYE PHOTIC STIMULATION PHOTORECEPTORS, INVERTEBRATE ULTRAVIOLET RAYS SPECTROPHOTOMETRY, ULTRAVIOLET ADAPTATION, OCULAR