n. [L. nutrix, nurse]
A symbiotic relationship in which one partner obtains all the benefits.
n. [L. nutrire, to feed]
The ingestion, digestion and assimilation of food substances that includes their distribution within the organism, as well as the metabolism and ...
adj. [Gr. nyktos, night; pelagos, sea]
Coming to the water surface only at night.
n. [Gr. nymphe, bride]
1. (ARTHROPODA: Chelicerata)
The immature stage of Acari and Ixodoidea with a full complement of legs; an instar.
2. (ARTHROPODA: Insecta)
n.; pl. -phae [Gr. nymphe, bride]
1. (ARTHROPODA: Chelicerata)
In Acari, sclerites beneath the epigynium.
2. (MOLLUSCA: Bivalvia)
The immersed area behind the beak that ...
The second or third phase of postembryonic development; in Acari with six stases, the third phase comprised of proto-, deuto- and tritonymphs.
adj. [Gr. nymphe, bride; L. parere, to beget]
Bearing live young in an advanced stage of development; see pupipara.
n. [Gr. nymphe, bride; chrysallis, gold colored pupa]
In chigger mites, a nonfeeding, prenymph; a calyptostasic protonymph.
adj. [Gr. nymphe, bride; eidos, form]
Nymphal phase instars that cannot be homologized with nymphal instars of other species.
A neoteinic reproductive with wing buds; a second-form reproductive; secondary reproductive; a brachypterous neoteinic.
n. [Gr. nymphe, bride]
The process of transforming into a nymph or a pupa.
adj. [L. ob, inverse; conic, cone]
Inversely conical; in the form of a reversed cone.
adj. [L. ob, inverse; cor, heart]
adj. [L. obesus, fat]
Distended; enlarged; corpulent.
adj. [L. ob, inverse; imbrex, tile]
Having regularly overlapping scales; see obsite.
adj. [L. ob, inverse; lanceolatus, spear-like]
adj. [L. oblatus, spread out]
Flattened; pertaining to a spheroid of which the diameter is shortened at two opposite ends; flattened at the poles.
adj. [L. obligare, to be required]
Pertaining to the inability to live in a different environment; see facultative.
A parasite that cannot exist without a host during all or some portion of the life cycle; see facultative parasite.
An organism that is physiologically dependent upon a symbiotic relationship with another; see facultative symbiont.
adj. [L. ob, inverse; liquis, awry]
Slanting; deviating from the perpendicular, or a particular horizontal direction, but not perpendicular to it.
Innermost muscle layer of body wall; may form oblique or nearly transverse fascicles between bands of the longitudinal muscles.
A thin layer ...
A slanting cross wing vein.
adj. [L. obliteratus, erased]
adj. [L. oblongus, rather long]
Elliptical; elongated; longer than broad.
In aculeate Hymenoptera, the innermost or posterior pair of plates immovably fixed on each side of the bulb and stylet of the sting.
n. [L. oblongus, rather long]
In Coleoptera wings, a special oblong cell formed when M 1 is connected with M 2 by means of one or two cross veins.
adj. [L. ob, inverse; ovate, egg-shaped]
Inversely eggshaped with narrower end downward.
adj. [L. ob, inverse; pyrum, pear; forma, shape]
adj. [L. obscurus, covered]
1. Dark; dark of color; dim.
2. Remote; hidden.
3. Not well defined.
adj. [L. obsitus, barred]
Refers to a surface covered with equal scales or other objects; see obimbricate.
n. [L. obsoletus, to wear out]
1. The process of gradual reduction or disappearance of a taxon.
2. A gradual cessation of a physiological process.
adj. [L. obsoletus, to wear out]
Obscure; not distinct; atrophied; imperfectly developed.
A pupa in which the appendages are glued down to the body by a secretion produced at the larval/pupal molt; see exarate pupa.
adj. [L. obtectus, covered over]
Covered; enclosed within a hard covering.
n. [L. dim. obturare, to plug or close]
In Anoplura, a connective-like tissue structure that divides the hemocoel of the head from the thoracic ...
n. [L. obturare, to plug or close]
Any structure that closes off a cavity.
adj. [L. obtusus, blunt]
Blunt or rounded at the extremity; not pointed; see acute.
n. pl. [L. obtusus, blunt; lingua, tongue]
In a former classification, those bees with short tongues having an obtuse or bifid tip; see ...
adj. [L. obumbrare, to over-shadow]
Overhanging, or partially concealing.
adj. [L. obvertere, to face]
1. Looking head on.
2. Having the base narrower than apex.
3. Being a counterpart.
adj. [L. obvolvere, to wrap around]
Bending downward and inward.
adj. [L. occiput, back of the head]
Pertaining to the occiput or the back part of the head.
The area of the cranium between the occipital and postoccipital sutures.
In Ichneumonidae Hymenoptera, a subcircular carina on the hind aspect of the head, between the vertex and hind margin of the compound eyes and the ...
A projection on either lateral margin of the postocciput with which the cephaliger of a cervical sclerite articulates; cervical condyle.
The posterior opening of the head into the cervix; neck foramen; see foramen magnum.
In Mallophaga, the posterior margin of the head.
In Conchostraca, the angulated indentation at the ear of the cephalon.
A transverse suture sometimes present on the back of the head that separates the vertex from the occiput dorsally and the genae from the postgenae ...
n. pl. [L. occiput, back of the head]
An unpaired row of dorsal cilia on the head.
n. [L. occiput, back of the head]
1. The dorsal posterior part of the cranium, between the occipital and postoccipital sutures; in many the boundaries ...
In Cirripedia, the margin of the scutum and tergum bordering the orifice.
In Cirripedia, small projections on the occludent scutal margin interdigitating with the teeth on the margin of the opposed scutum.
In Heteroptera larvae, a semicircularly shaped plate located below the lateral pore in the ostiole; functioning in scent ejection in any horizontal ...
adj. [L. occludare, to close]
An organ or muscle that closes an opening.
adj. [L. occulere, to hide]
Hidden from sight.
The open sea beyond the edge of the continental shelf.
In Hymenoptera, a concave area, varying in form and size, occupying the median portion of the frontal area.
In Diptera, bristles arising close to the ocelli; in the ocellar triangle.
The brain centers of the ocelli, found in the outer part of the ocellar pedicels.
In Lepidoptera larvae, six ocelli on the lateral area of the larval head, dorsal four forming the quadrant of a circle, ventral two farther apart.
Long slender nerve stalks connecting the facial ocelli with the protocerebrum.
In Diptera, the triangular region bearing the ocelli and often bounded by grooves or depressions.
adj. [L. dim. oculus, eye]
Eye-like; spotted; having ocelli or eye-like spots.
n.; pl. ocelli [L. dim. oculus, eye]
1. The simple eyes or eyespots, occurring singly or in small groups, found in many invertebrates.
2. (ARTHROPODA: Crustacea)
adj. [Gr. ochros, yellow brown]
Pale yellow; brownish-yellow.
adj. [Gr. ochros, yellow brown; leukos, white]
Yellowish; whitish yellow; buff.
adj. [Gr. okto, eight; aktis, ray]
A modified hexactine spicule with 8 rays.
adj. [Gr. okto, eight; meros, part]
Organs or parts of organs arranged in series of 8.
adj. [Gr. okto, eight; aploos, onefold]
Cells having 8 chromosome sets in the nucleus (8n).
adj. [Gr. okto, eight; pous, foot]
Bearing 8 tentacles, feet or arms; octopody n.
adj. [Gr. okto, eight; prostates, one who stands before]
Having 8 prostates.
adj. [Gr. okto, eight; theke, case]
Having 8 spermathecae.
adj. [L. oculus, eye]
Of or pertaining to the eyes.
A knob on the inner surface of the carapace joining the lower and upper orbital margins with the basal segment of the antenna; functioning to ...
In Mallophaga, a lateral emargination of the head in front of the eyes.
In Mallophaga, a black spot in the eyes.
In Mallophaga, small hairs on the posterior half of the ocular emargination, may extend on the temporal margin.
On some Coleoptera, a projecting thoracic lobe.
In some Malacostraca, the anterior projection on the eyestalk.
A movable peduncle (eyestalk) with a compound eye at the distal end, sometimes with two or three segments, sometimes retractable.
Plates at the terminal end of the ambulacral areas.
1. In some Pseudococcidae, well developed sclerites extending completely around each side, each bearing a row of 7 simple eyes near anterior margin, plus ...
In Diptera, one of several setae occurring in a line near the posterior margin of each compound eye.
In the Nautilus , an opening on the lateral shell margin accommodating the normal arc of vision of the eyes.
An annular inflection surrounding the compound eyes.
A tubular depression in the brain containing the pigment of the eyespots or eyes.
In Hemiptera, supplementary eyes with prominent facets on the posterior area, in addition to the compound eyes.
n.; pl. -ia [L. oculus, eye]
1. The area around the simple eye or eyes of larvae.
2. In Hymenoptera sawflies, the pigmented area.
adj. [L. oculus, eye; fero, bear]
adj. [L. oculus, eye; movere, to move]
The nerve center of muscle that moves the eye.
n.; pl. oculi [L. oculus, eye]
The eye; a spot shaped like an eye.
adj. [Gr. odous, tooth]
adj. [Gr. odous, tooth]
Of or pertaining to the Odonata.
n. [Gr. odous, tooth]
The stomatal armature generally in the form of a tooth or teeth originating from the anterior stoma (cheilostome); see onchium.
n. [Gr. odous, tooth; blastos, bud]
Cells in the radular sac that secrete the radular teeth.
n. [Gr. odous, tooth; phoreus, bearer]
1. (MOLLUSCA: Gastropoda)
The cartilaginous supporting organ of the radula, tongue or lingual ribbon possessing a complicated ...
n. [Gr. odous, tooth; stylos, column]
A stylet derived from an odontium terminating with a dorsally oblique aperture, and originating in the ...
A chemical trace laid down by one insect to be followed by other insects of the same species or nest; the substance is called trail pheromone or trail ...
- see ecoOnline Dictionary of Invertebrate Zoology 627.
n. pl. [Gr. oinos, wine; kytos, container]
Large cells in a group on either side of each abdominal segment, between the bases of the epidermal cells and ...
n. [Gr. oinos, wine; kytos, container; eidos, form]
Round or oval cells, with darkly staining nucleus and clear, uniform, weakly acidophil cytoplasm. ...
A list of names or works suppressed or declared invalid by the ICZN.
A list of names or works declared to be valid by the ICZN.
adj. [F. ogive, pointed arch]
Bearing the shape of an arch.
n. [Gr. oikos, house; sitos, food]
An attached or stationary commensal or parasite.
adj. [L. olfacere, to smell]
Pertaining to the sense of smell; among invertebrates, the organs are variously placed: antennae of insects and other arthropods, tips of the palpi ...
Papilla found on Teuthoidea, Sepiidae and Vampyromorpha on either side of the head near the neck.
In Octopodidae, olfactory pits on either side of the head near the neck.
n. [Gr. oligos, few; genos, descent]
A gene determining a pronounced phenotypic effect; see polygenes.
n. [Gr. oligos, few; gyne, female]
Several functional queens in a colony.
An egg with a small amount of yolk; isolecithal; see centrolecithal egg, telolecithal egg.
adj. [Gr. oligos, few; lektos, chosen]
Selecting only a few, as bees collecting pollen from only a few kinds of flowers; oligotropic.
adj. [Gr. oligos, few; meros, part]
Having fewer parts or organs than other related forms. oligomery n.
adj. [Gr. oligos, few; nephros, kidney]
Having few excretory tubules.
adj. [Gr. oligos, few; neuron, nerve]
Having very few wing veins.
adj. [Gr. oligos, few; phagein, to eat]
Feeding on only a few species of food plants; see monophagous.
adj. [Gr. oligos, few; phyle, tribe]
Derived from a few ancestral forms; see monophyletic.
adj. [Gr. oligos, few; pneustikos, of breathing]
Having one or two functional spiracles on each side, including the amphipneustic, metapneustic and ...
n. [Gr. oligos, few; pous, foot]
1. Bearing few legs.
2. Having fully developed thoracic legs; see polypod, protopod.
adj. [Gr. oligos, few; pyren, stone of a fruit]
With reduced number of functional spermatozoa; see apyrene, eupyrene.
adj. [Gr. oligos, few; sapros, putrid]
Describing a body of water with slow organic matter decomposition and high oxygen content.
n. [Gr. oligos, few; taxis, arrangement]
Weak development of secondarily formed organs (usually not numerous).
adj. [Gr. oligos, few; thermos, heat]
Having a tolerance for low temperatures.
adj. [Gr. oligos, few; tokos, offspring]
Having a small number of young.
n. [Gr. oligos, few; trichos, hair]
Few, weakly developed setae.
adj. [Gr. oligos, few; trophe, food]
Pertaining to freshwater bodies poor in plant nutrients and unproductive.
adj. [Gr. oligos, few; tropikos, turning]
Visiting only a few kinds of flowers for nectar; oligolectic; see monotropic, polytropic.
adj. [Gr. oligos, few; xenos, host]
Said of certain parasites adjusted to live in a limited number of hosts; oligoxeny n.
adj. [Gr. oligos, few; zoon, animal]
Having a few species or numbers of animals in a particular habitat.
adj. [L. oliva, olive]
Resembling or having the color of olive green.
adj. [L. oliva, olive; forma, shape]
Oval; resembling an olive in shape.
n. [Gr. olynthus, unripening fig]
In calcareous forms, a post-settlement stage; in asconoid forms, remains as adult form.
A branchlet issuing from the terminal axial of the main-axil.
n. [Gr. ommation, little eye]
A compound eye.
n.; pl. -ia [Gr. ommation, little eye; idion, dim.]
One of the component units of a compound eye, consisting essentially of an optical (light gathering) part and ...
n. [Gr. omma, eye; eidos, form]
In some Arachnida, a light colored spot on the posterior body segment.
n. [Gr. omma, eye; pherein, to bear]
A movable process bearing an eye, as in snails; may be fused with the tentacles.
n. [Gr. omma, eye; chroma, color]
A group of pigments, products of tryptophane metabolism, found in eyes and epidermis of certain invertebrates; it is apparently not ...
adj. [L. omnis, all; vorare, to devour]
Capable of obtaining nourishment from both animal and plant tissue.
adj. [Gr. omphalos, the navel]
Referring to the orifice (excluding ostiole) of the metathoracic scent gland of Heteroptera as median and unpaired.
adj. [Gr. omphalos, the navel]
Having a shell with an umbilicus.
In Enoplida, the basal plate of the onchium.
n.; pl. onchia [Gr. onkinos, hook]
Stomatal armature, generally in the form of a tooth or teeth originating from the posterior stoma (esophastome); see odontium, ...
n. [Gr. onkinos, hook; merakidion, youth]
1. A term for an embryo in the egg.
2. The ciliated larva of a monogenetic trematode.
adj. [Gr. onkos, swelling; gennaein, to produce]
n. [Gr. onkos, swelling; physis, growth]
Any extension of an arthrodial membrane, usually in the form of a more or less hyaline intumescence; see ...
n. [Gr. onkinos, hook; sphaira, ball]
The shelled embryo; a hexacanth; the first larval stage.
n. [Gr. onoma, name; pherein, to carry]
A name-bearer; a type.
n. [Gr. on, being; genesis, beginning]
The development or course of development of an individual organism from zygote to maturity; as distinguished from that of a species; ...
n. pl. [Gr. onyx, claw; chaite, hair]
Microscleres with long, thin oxeote spicules, roughened with spines.
n.; pl. -ia [Gr. onyx, claw]
A general term for a pad between the tarsal claws.
n.; n. pl. [Gr. onyx, claw; phorein, to carry]
A phylum of terrestrial animals comprised of a single class or order of the same name, frequently referred to as Peripatus ; ...
n. [Gr. oion, egg; blastos, bud]
A cell from which an ovum develops.
n. [Gr. oion, egg; blastos, bud]
A fertilized egg; an oosperm.
n. [Gr. oion, egg; L. captus, capture]
A controlling spincter of the oviduct that allows mature oocytes to enter the proximal oviduct.
n. [Gr. oion, egg; kystis, pouch]
The cystic form in the parasitic protozoans (Apicomplexa), resulting from sporogony; may be hard covered, with a resistant membrane ...
n. pl. [Gr. oion, egg; kytos, container]
An immature female gamete that undergoes meiosis, giving rise to ova or eggs.