ocellus


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Related to ocellus: simple eye, ocelli

ocellus

(pl. ocelli): see eyeeye,
organ of vision and light perception. In humans the eye is of the camera type, with an iris diaphragm and variable focusing, or accommodation. Other types of eye are the simple eye, found in many invertebrates, and the compound eye, found in insects and many other
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ocellus

[ō′sel·əs]
(invertebrate zoology)
A small, simple invertebrate eye composed of photoreceptor cells and pigment cells.
(petrology)
A phenocryst in an ocellar rock.
References in periodicals archive ?
Notauli posteriorly separated; minimum distance between notauli longer than half of posterior ocellus breadth; head and scutum dull and granulated, or shiny, punctate, without sculpture among punctae 3
7 mm SL) has a faint ocellus, a remnant of the typical juvenile marking, in the middle of the posterior dorsal fin between the eighth and eleventh soft rays.
Head ochraceous, mandibular plate broadly margined with brown laterally along entire length and medially at its apical portion; clypeus dark brown; base of head blackish brown, outline of blackish area projecting anteriad before ocellus.
Compound eye surrounded by several hyaline lenses and ocellus slightly smaller:
Head: 1- Ocellar tubercle with a row of setae separating the anterior ocellus from the others: (0) absent; (1) present.
2x width of frons), with sides subequal; anterior ocellus slightly larger than posterior.
1B); area anterior to each ocellus pale brown; anteocular region laterally with brown stripe from antennal tubercle to middle of eye (Fig.
Dark spot behind gills relatively 3 small, forming a weak ocellus (or semi-ocellate dark spot) and followed posteriorly by dark brown bar (consisting of 2-3 merged spots in vertical row) 2b.
Frontal costa expanding between the antennae, decidedly converging below medium ocellus, flat with scattered impressed punctae from fastigium to medium ocellus and slightly convex between lateral carina; a dark subquadrate spot above antennae (Fig.
Frons narrow, distance of vertical seta to lateral ocellus shorter than distance between lateral ocelli; occiput with several white setulae ventrally; mouth opening with long white setulae .