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Related to ocellus: simple eye, ocelli


, pl.


(ō-sel'ŭs, -lī),
1. The simple eye found in many invertebrates. Synonym(s): eyespot (2)
2. Facet of the compound eye of an insect.
[L. dim. of oculus, eye]


n. pl. ocelli (ō-sĕl′ī′)
1. A simple eye, found in many invertebrates, consisting of a number of sensory cells and often a single lens.
2. A marking that resembles an eye, as on the tail feathers of a male peacock; an eyespot.

o·cel′lar (ō-sĕl′ər) adj.


a single eye with a single lens found in insects and some other invertebrates.
References in periodicals archive ?
belongs to the "Coptosoma-group," defined by the following combination of characters: ocellus situated near to eye (ratio of distance between eye and ocellus to interocellar distance less than 0.
Frontal costa expanding between the antennae, slightly converging below medium ocellus, then expanding again, flat with scattered impressed punctae from fastigium to clypeus and slightly convex between the lateral carina; a large subtriangular spot above the antennae and below lateral ocelli (Fig.
Frontal ridge smooth, nonsulcate, obsolete below median ocellus.
has a broad frons, the distance of the vertical seta to lateral ocellus being greater than the distance between the lateral ocelli (Fig.
Pekkarinen (1995) compared measurement data for seven parameters (oculo-malar length, distance between compound eyes on vertex, postocellar width, distance between posterior ocellus and occipital margin, clypeal width, clypeal length and pronotal width), along with features of the male genitalia (upper inner margin of the paramere and tip of the aedeagus) and likewise concluded that D.
Fine structure of the ocellus of Sarsia tubulosa (Hydrozoa, Anthomedusae).
Forewing, upper side: ground color gray, with purplish iridescent scales covering most of the wing, except along the outer margin; one small black submarginal ocellus surrounded by yellowish scales in each space between [R.
Frontal ridge above medial ocellus with thickened carinae, widely but shallowly sulcate, interrupted just above the medial ocellus by a transverse ridge; below the ocellus, frontal ridge increasingly obsolete.
Vertex and gena very sparsely micropunctate, shining; frons, supraclypeal area, clypeus somewhat densely punctate, shining, malar space rugosely sculptured, dull; pubescence whitish, shorter than the diameter of lateral ocellus.
6 of way to median ocellus, tapered, strongly concave and with upper end truncate and free from frons (Figures 1, 4); frons with little median prominence; lateral ocellus separated from eye by slightly less than its own maximum diameter.