abdomen: one of the three body segments in insects; the most posterior segment containing the heart, reproductive organs, and digestive organs
alate: winged
antenna (pl. antennae): pair of segmented, sensory structures (feelers) projecting from the heads of insects
anterior: situated near the front of the body; nearer to the head
apical: far from the base, the tip of a structure
appendage: any limb or organ that is attached to the insect's body by a joint
apterous: without wings
arista: a large bristle located on the apical antennal segment for dipteran species
axil: the upper hollow where a leaf or flower attaches to a stem
basal: at or near the base of a structure
bronzing: smooth, dark brown discoloration to plant tissues as a result of insect damage
calyx: whorl of residual flower parts that include the sepals, found at the stem end of a fruit
canopy: referring to the crown of a tree that includes the leaves, stems, and branches
caterpillar: common name for larval lepidopterans (butterflies and moths)
cauda: a v-shaped structure extending from the rear of the aphid abdomen
cercus (pl. cerci): segmented, paired appendages at the rear of the abdomen, usually triangular and short in grasshoppers
chewing mouthparts: mouthparts designed for biting and chewing; mandibles move from side to side with overlapping edges that cut like scissors as well as surfaces for grinding; characteristic of orthopterans
chlorosis: yellow or white spotting on leaves and fruit resulting from feeding by certain pests
chrysalis: another term for the pupa of a butterfly
cilia: slender hairs that outline the forewings and represent modified setae; a diagnostic characteristic of thrips (order Thysanoptera)
clavate: word used to describe antennae in which the last, terminal segments are wider towards the tip forming a club-like shape
clypeus: a sclerite on the head of the insect positioned below where the antennae attach and articulated with the labrum on the other side
cocoon: the protective covering around the pupa of some insects
compound eye: an eye comprised of many individual eye elements called ommatidia that each have a lens; the main visual organ in insects
concave: shaped or curved like the inner surface of a sphere
convex: shaped or curved like the outward surface of a sphere
cornicles: paired, triangular-shaped tubes projecting from the rear of an aphid abdomen; also referred to as siphunculi
costal fold: a fold along the leading edge of the lepidopteran forewing that contains scent scales used to attract members of the same species
coxa: basal segment of insect leg that is connected to the body by a joint
crawler: the mobile first instar of many scale species
cremaster: a hook or series of hooks at the terminal end of the abdomen in some lepidopterans, used to attach the butterfly or moth to the pupation site
crochet (pl. crochets): small, hook-like structures that extend in a circle from the prolegs found on larval lepidopterans
diapause: temporary cessation of development caused by a physiological response to unfavorable conditions
distal: appendage or part farthest from the body
dorsal: the upper surface of an insect
eclosion: the emergence of an insect from an egg or pupa
elytron (pl. elytra): hardened or sclerotized pair of forewings in beetles
emergence: used to describe the completion pupation that culminates in the appearance of the adult form of an insect
ensiform: word used to describe antennae that are sword-like and broad at the base, but narrowing to the tip
epidermal cells: layer of plant cells immediately beneath the waxy covering on the surface (the cuticle)
exudate: fluid released naturally from the body openings of insects or from wounds in insects or plant tissues
eyespots: markings on an insect, usually the wing, that resemble a large eye
femur: from the base of the insect body, the femur is the third segment of the insect leg, situated between the trochanter and tibia
filament: long thread-like structures extending from the body of insects, typically from the abdominal segments (e.g., mealybugs)
filiform: type of antenna that is uniformly thin and threadlike throughout its length
flagellum (pl. flagella): the outermost part of the antenna, beyond the scape and pedicel, usually divided into many subsegments (flagellomeres)
flush: period of rapid growth in the terminal shoots of citrus trees that may be associated with flowering or may be vegetative
foliar: relating to foliage (leaves)
forewing: the anterior (closest to the head) pair of wings in insects
frass: pellets of very dry excreta produced by some insects
furcula: forked projection from the posterior edge of the abdomen and overlying the supra-anal plate of male grasshoppers
gall: a distorted area of stem or leaf tissue arising from the plant's response to attack by certain pests and pathogens
gaster: the bulbous part of the ant abdomen located behind the waist (petiole)
generation: the time it takes for an insect to develop from egg to adult
geniculate: adjective used to describe antennae in which there is an abrupt bend or 'elbow' along the length of the antennae
genitalia: external reproductive structures
girdling: removal of the bark, phloem, and cambium tissues around the entire circumference of the effected plant part (branch, root, or trunk) that results in the death of the wood beyond that point; characteristic damage inflicted by specific insects like beetle larvae
gravid: female that is bearing eggs
gregarious: exhibiting the behavior of moving or feeding in a group of individuals of the same species; early instars of many insects feed in groups
grub: an immature stage in the life cycle of insects; larvae of beetles are often referred to as grubs
haltere (pl. halteres): the club-shaped, modified hindwing of flies (order Diptera) that plays a role in moderating balance and stabilization in flight
head: one of the three main body segments in insects; the anterior-most segment containing the many sensory structures including the eyes, antennae, and mouthparts
hemelytra: the forewings typical of many hemipterans; the base of the wing is leathery and the tip of the wing is membranous
hemimetabolous: simple metamorphosis that consists of a series of molts and lacks a true pupal stage
hindwing: the posterior or rear pair of wings in insects
holometabolous: complete metamorphosis that includes egg, larval, pupal, and adult phases
honeydew: the sugar-rich waste product excreted by aphids, mealybugs, and scales insects as a result of feeding on the phloem of plants
host plant: the plant the provides sustenance for an insect
host range: the range of species that a particular organism can feed on to achieve successful growth and reproduction
hyaline: transparent and glassy
imago: the adult stage of an insect
immatures: term used to describe the sub-adult stages of insects that do not undergo complete metamorphosis; see also nymph
instar: immature stages (larva or nymph) of insects in between molts
integument: the outer covering of an insect's body
invasive: term used to describe species that are not native and have the ability to adversely effect habitats they invade either ecologically or economically
larva (pl. larvae): the immature or juvenile stage of certain groups of insects that undergo complete metamorphosis that includes a pupal stage; these juveniles often look very different from the adult form and are missing structures (e.g., wings) that are found in the adult
lateral: with an orientation pertaining to the side
maculate: spotted
maggot: an immature stage in the life cycle of insects; fly larvae are often referred to as maggots
mandibles: the jaws of insects with chewing mouthparts
medial: situated in or closest to the middle
membranous: with the same character as a membrane, typically used to refer to structures like wings that are clear and translucent like a membrane
mesothorax: the second or middle segment of the thorax
metathorax: the third and last segment of the thorax
mobile: able to move
molt: process of shedding the external skeleton during periods of growth; occurs between successive instars of a larva or nymph
moniliform: type of antennae where successive round segments make the antenna as a whole appear like a string of beads
motile: able to move
necrotic: the damage caused by cell death (necrosis) in plants or other organisms, often a result of insect feeding on plants, and displayed as brown or black coloration of tissues
nymph: the immature or juvenile stages of insects that do not undergo complete metamorphosis; look similar to the adult and develop to the adult stage through a series of incremental changes that does not include a pupal stage
ocellus (pl. ocelli): the simple eye of an insect that consists of a single, bead-like lens, typically located at the top of the head in insects that undergo complete metamorphosis; absent in lepidopterans and reduced in many other species
oviposition: the act of depositing eggs
ovipositor: a tubular structure extending from the abdomen of female insects that is used to lay eggs
ovisac: structure attached to the body that contains eggs; produced by many scale insects
parthenogenesis: a form of asexual reproduction in which a female produces eggs without fertilization by a male
pedicel: from the base, the second segment of the antenna, located between the scape and the flagellum
petiole: the first segment behind the metathorax that connects the thorax to the gaster of an ant; often referred to as a "waist" because the segments are slender and appear as a constriction between the two body sections
pheromone: chemical substance secreted by an animal that influences the behavior of another animal
piercing-sucking mouthparts: labium encloses the mandibles and maxillae, which are modified into stylets for piercing and sucking; characteristic of hempiterans
posterior: orientation pertaining to the rear of the body
postpetiole: the second segment of the "waist" which, if present, is located directly behind the petiole; only present in certain familes of ants
pre-pupa: the non-feeding last instar larva of insects that undergo complete metamorphosis
probing-sucking mouthparts: mouthparts are modified into a long, slender proboscis specialized to probe flowers and suck out nectar; characteristic of butteflies and moths
proleg: unsegmented, fleshy, foot-like structure extending from the abdomen of many larval lepidopterans that aids in locomotion, but are not true legs like those found extending from the thorax
pronotum: the dorsal surface of the first thoracic segment
propupa: a non-feeding stage in the development of thrips and male scales immediately before formation of the pupa
prothorax: the first segment of the thorax
pterostigma: a thickened cell on the outer margin of the wing in some insects
pulp: the soft, moist, internal part of the citrus fruit, beneath the rind and albedo layers
pupa (pl. pupae): the non-feeding, immobile developmental stage of holometabolous insects during which the larva develops into an adult that is very different in form
puparium: the rigid outer shell formed from the discarded larval skin that protects the pupa of certain flies
rasping-sucking mouthparts: mouthparts that are modified to rasp or scrape the surface of plant tissues and suck up the fluid that flows from damage tissues; characteristic of thrips
ring scar (or halo mark): a circular blemish on fruit caused by pest damage to the rind around the calyx during early fruit development
scape: basal segment of the antenna
scent gland: a gland which secretes an offensive, odorous fume for protection
sedentary: not mobile
sessile: not mobile
seta (pl. setae): stiff hairs or bristles
setaceous: word used to describe antennae in which the flagellum is reduced and tapers gradually from the base to the tip
silk: a natural fiber produced by some insects that can be utilized to construct shelters, leave a trail, build a cocoon, etc.
siphunculi: paired, triangular-shaped tubes projecting from the rear of an aphid abdomen; also referred to as cornicles
solitary: insects that feed or move about individually, not in groups
spine: a thorn-like outgrowth of the integument (exoskeleton) that is not separated from it by a joint
sponging mouthparts: mouthparts are modified for sponging up liquid food by capillary action; saliva containing digestive enzymes may be used to liquify solid food; characteristic of dipterans
spur: a spine-like process of the integument (exoskeleton) that is connected by a joint
stigma (pl. stigmata): prominent, darkened cells on the forewings of some male lepidopterans that produce pheromones to attract females
tarsus (pl. tarsi): the last, distal segment of the insect leg, composed of sections called tarsomeres, usually ending in a claw
thorax: one of the three main body segments in an insect, located between the head and abdomen, where the wings and legs of the insect attach
tibia: from the base of the insect body, the tibia is the fourth segment of the insect leg, situated between the femur and the tarsus
trochanter: from the base of the insect body, the second segment of the insect leg, situated between the coxa and the femur
tubercle: a small raised bump or rounded protuberance, typically, describing a raised bump on a caterpillar that bears a spine orthe rounded bumps that the antennae of aphids extend from
tympanum (pl. tympana): a vibrating membrane that serves as an auditory organ in some insects
ventral: bottom surface of the body
wing pads: undeveloped or incomplete wing structures that are found on the immature individuals of insects that do not undergo complete metamorphosis, e.g., stink bugs, leaf-footed bugs, grasshoppers
Citrus Pests
Content last updated June, 2012
idtools.org
