ocellus

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o·cel·lus

 (ō-sĕl′əs)
n. pl. o·cel·li (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.

[Latin, diminutive of oculus, eye; see okw- in Indo-European roots.]

o·cel′lar (ō-sĕl′ər) adj.

ocellus

(ɒˈsɛləs)
n, pl -li (-laɪ)
1. (Zoology) the simple eye of insects and some other invertebrates, consisting basically of light-sensitive cells
2. (Biology) any eyelike marking in animals, such as the eyespot on the tail feather of a peacock
3. (Botany) botany
a. an enlarged discoloured cell in a leaf
b. a swelling on the sporangium of certain fungi
[C19: via New Latin from Latin: small eye, from oculus eye]
oˈcellar adj
ocellate, ocellated adj
ˌocelˈlation n

o•cel•lus

(oʊˈsɛl əs)

n., pl. o•cel•li (oʊˈsɛl aɪ)
1. the simple eye of many invertebrates, consisting of retinal cells, pigments, and nerve fibers.
2. an eyelike spot, as on a peacock feather.
[1810–20; < Latin: little eye, diminutive of oculus eye; see -elle]
o•cel′lar, adj.
oc•el•lat•ed (ˈɒs əˌleɪ tɪd, oʊˈsɛl eɪ tɪd) oc•el•late (ˈɒs əˌleɪt, oʊˈsɛl ɪt, -eɪt) adj.

o·cel·lus

(ō-sĕl′əs)
Plural ocelli (ō-sĕl′ī′)
1. A small, simple eye or eyespot, found in many invertebrates.
2. A marking that resembles an eye, as on the wings of some butterflies.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.ocellus - an eye having a single lens
eye, oculus, optic - the organ of sight
ommatidium - any of the numerous small cone-shaped eyes that make up the compound eyes of some arthropods
2.ocellus - an eyelike marking (as on the wings of some butterflies)ocellus - an eyelike marking (as on the wings of some butterflies); usually a spot of color inside a ring of another color
marking - a pattern of marks
Translations
References in periodicals archive ?
Some web-building spiders, including those in the genus Storena, even have underfocused and therefore only crudely image-forming eyes (Land, 1985), reminiscent of the optics of the dorsal ocellar system in some insects (Goodman, 1981).
Plate V: Features around the ocellar triangle and the metanotum 10a.
rayahdensis are bare and not clothed with long erect and tufted black hairs, and neither the ocellar tubercle nor the occiput bear long erect black hairs as in P.
Head higher than wide in frontal view, in lateral view eyes occupying more than half of the top of the head, crest and ocellar tubercle well developed (Fig.
Face, frons and vertex dull gold pruinose, mystax orange-yellow, ocellar macrosetae orange-brown.
quimbaya is easily differentiated from the female of Batrachophthalmum rufiventre, by having ocellar seta reduced; orbital seta present; lateral vertical seta reduced, almost indistinguishable from setulae around it; one dorsocentral seta; wing with wide and discontinuous median band; abdomen and legs brown, except mid tarsomeres and apical half of hind tibia yellow and hind tarsomeres whitish.
DESCRIPTION: Head: Clypeus (tylus) unarmed, apically globose, weakly raised, extending anteriorly to and laterally weakly higher than juga; juga unarmed; antennal segment I stout, thickest, slightly curved outward, attenuated at base, and shorter than maximum length of head; segments II and III slender, cylindrical, and IV fusiform and barely thickened; each antennal segment clothed with scattered, short, semidecument, silver, bristle-like setae; antennal segments I to III densely tuberculate; ocellar tubercle barely raised; postocular tubercle protuberant; labial segment I short, reaching posterior half of head.
rufipes, the erect hairs of these areas are in general long and abundant; on vertex and preoccipital border at least as long as median ocellar diameter; on mesoscutum present along anterior margin as well as on anterior one-third of disc medially; on disc of mesoscutellum abundant, about as long as (about twice as long as median ocellar diameter) or slightly shorter than those on the distal margin.
Species of Stenomicra differ from other Periscelididae by the presence of two reclinate fronto-orbital setae (lower seta occasionally mesoclinate); frons lacking interfrontal setae; ocellar setae absent; postpronotum lacking a well-developed seta; eyes microsetulose, sometimes sparsely so; katepisternum bearing 1 prominent seta; hindfemur lacking anterodorsal, preapical seta; supra-alar seta lacking; lateral scutellar setae 1 pair, apical; wing with anal lobe greatly reduced; costa long, extended to vein M; alula indistinct; vein CuA2 weak or lacking; cell cup usually lacking (Mathis & Rung, in press).
Abbreviations used in the descriptions are: F, S, T, OD and PW for antennal flageller segment, metasomal sternum and tergum, ocellar diameter, and puncture diameter, respectively.
65 wide near front of coxae III, where widest, reddish orange, darkest posterolaterally, without deep pits; pale ocellar areas obsolete, covered (like most of surface) with white, calyx-shaped, scale-like setae; tiny tubercles (about one-fifth size of scale-like setae) scattered over most of surface; with three depressions: one along midline, one on each side occupying middle one-third of length.