The operculum papillare is the
iris found in the eyes of
elasmobranchs (
skates,
shark
Sharks are a group of elasmobranch cartilaginous fish characterized by a ribless endoskeleton, dermal denticles, five to seven gill slits on each side, and pectoral fins that are not fused to the head. Modern sharks are classified within the ...
s and
rays).
It can undergo
pupillary light reflex
The pupillary light reflex (PLR) or photopupillary reflex is a reflex that controls the diameter of the pupil, in response to the intensity ( luminance) of light that falls on the retinal ganglion cells of the retina in the back of the eye, t ...
to such an extent that the eye is essentially shut off. It is sometimes called the golden iris because of the shine it sometimes causes.
References
Fish anatomy
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