Order Homoptera Aphids, Scale Mealybugs and Allies

Order Homoptera

Aphids, Scale Mealybugs and Allies

Homopterans

Order HomopteraAphidsScaleMealybugsWhitefliesPsyllidsLeafhoppersTreehoppers, etc.

Homopterans

Simple metamorphosisPiercing-sucking mouthparts Some with wingsMostly all pests – few predators Source of dyes and shellac

Homopterans

LocationsPlant feeders found on or near plantsSome found underground feeding on rootsGreenhouses

Homopterans

DamageDeformed leaves, flowers and fruitLoss of plant vigor and diebackSooty mold fungi results from “honeydew” wasteTransmits diseases to plants inc. Pierce’s Disease of Grapes, Oleander Scorch, Citrus Tristeza Virus, Rose Mosaic Virus

Homopterans

ControlsVarious insecticidesDormant oilsBiological controls inc. parasitic wasps, ladybird beetles, preying mantids, etc.The garden hose

Homopterans

Controls (cont’d)Use of low nitrogen fertilizersGood pruning practicesControl ants Sanitation

AphidsFamily Aphididae

Aphids

Aphids

Piercing- sucking mouthpartsFeeding causes curling or wiltingMosaic viruses, wilts, stuntingSecondary host plants

Aphids

ControlsPredators inc.: lady beetles, lacewings, syrphid fliesParasites – Braconid and Chalcidoid parasitic waspsRemoval of secondary host plants

Aphid Life Cycle

Most species overwinter as eggsSpring – eggs hatch into femalesFemales reproduce parthenogenetically –

without fertilization

Aphid Life Cycle

Live young are born without wings (apterous)

As population increases alate (winged) forms are produced

Alate forms often migrate to a secondary host plant

Aphid Life Cycle

Apterous forms are again producedAs days shorten alate forms are

produced againAlates migrate back to primary host plant

species

Aphid Life Cycle

New offspring are now sexual females and males

An egg population is produced to overwinter for the next spring

Aphid Life Cycle

Aphid/Parasite Life Cycle

Parasitic wasps parasitize aphids by laying an egg into an aphid

Aphid/Parasite Life Cycle

Wasp hatches and begins feeding on the live aphid

Eventually the aphid dies

Aphid/Parasite Life Cycle

The wasp pupates in the aphid “mummy”

Aphid/Parasite Life Cycle

Whiteflies

Family Aleyrodidae Piercing- sucking mouthpartsAdults are wingedWhite waxy or powdery dust covers

bodiesFirst instar is active “crawlers”

Whiteflies

Following instar stages appear like scale insects

Whiteflies undergo complete metamorphosis

Adult emerges from a pupa

Whitefly Family Aleyrodidae

Family Aleyrodidae

Whitefly Life Cycle

Family Aleyrodidae

Whitefly Life Cycle

Family Aleyrodidae

Soft Scales

Family Coccidae – about 85 speciesPiercing-sucking mouthpartsFemales – wingless, legs and sessile

Sessile – attached directly to stems, foliage or fruit

Soft Scales

Males – complete metamorphosis Males – gnat-like in appearanceMales have no mouthpartsMales wings or wingless

Soft Brown Scale

Family Coccidae

Hemispherical Scale

Family Coccidae

Soft Scales

Family Coccidae

Armored Scales

Family Diaspididae – over 300 speciesFemales – soft bodied w/hard unattached

shellShell formed by waxy secretionsFemales – eyeless and winglessMales – eyes and wings

Armored Scales

Parthenogenetic or sexual reproductionReproduction without fertilization

Some oviparous, some bear live young First instar – crawlersCrawlers spread the speciesMouthparts are inserted and insect

settles

Armored Scales

Female becomes sessileInfestations can be fatal to plantsTypically infest trees and shrubsSome important pests to orchards and

shade trees and various shrubs

Armored Scales

Two most common armored scaleSan Jose ScaleOystershell Scale

San Jose Scale

Introduced into California about 1880Possibly from AsiaSpread throughout the countryLive youngAttacks various plantsInfestations can be fatal

San Jose Scale

Male Female

Family Diaspididae

San Jose Scale

Circular in shape

Family Diaspididae

Oystershell Scale

Named for its shapeLays eggsEggs overwinter under shellAttacks most fruit treesAttacks various ornamental trees and

shrubs

Oystershell Scale

Family Diaspididae

Oystershell Scale

Leafhoppers

Family CicadellidaeVarious subfamilies and generaAbout 2500 species in North AmericaForms, colors and sizes varyVarious patterns Brightly colored

Leafhoppers

Found in most all situationsHost specific and have well defined

habitatsOverwinter as eggs or adultsMany are economically important pests

Leafhoppers

Few generations per yearCause 5 major types of plant damageSap-feeding in leaves Interferes with physiology – blockage to

phloem and xylemLays eggs in green twigsVector plant diseases Stunting and curling of leaves

Leafhoppers

Family Cicadellidae

GWSS & Blue-Green Leafhopper

Leafhoppers

Glassy-Winged Sharpshooter

Family CicadellidaeHomalodisca coagulata

GWSS – Xylella fastidiosa

Pierce’s Disease of Grapes Oleander Scorch

GWSS

Heavy feederCapable of infecting uninfected,

susceptible plantsBecomes a carrier by feeding on infected

plantsCan process 10x body weight/hourGWSS rain

GWSS Feeding

GWSS Feeding

GWSS Egg Masses

GWSS Egg Masses

GWSS Egg Masses

GWSS Nymphs and Adult

GWSS Nymphs

GWSS Adult

GWSS Distribution

GWSS Distribution

Treehoppers

Family MembracidaeVarious genera

Buffalo Treehopper

Treehoppers

Feeds most on trees and shrubs

Nymphs found in grasses and on herbaceous plants

One or two generations per year

Usually overwinter as eggs

Treehoppers

Damage caused by a few speciesEgg laying causes most damageEggs laid in twigs cause tip dieback Eggs overwinter in the barkNymphs feed on herbaceous plants

Buffalo Treehoppers

Adult and juvenile Buffalo Treehoppers

Treehoppers

Adult Treehopper

with Ants

Adult Treehopper

Treehoppers

Thorn-Mimic Treehoppers

Treehoppers

Spittlebugs

Family CercopidaeFeeds on trees, shrubs, herbaceous plants and

grassesNymphs – greenish to brownishHost specificFeeding can cause stunting to plantsNymphs hide in spittle frothFrothy mass can hold several nymphsAdults are activeEggs in late summer – hatch following springSingle generation per year

Spittlebugs

Spittlebug Nymphs

Spittlebugs

Spittle Masses

Spittlebugs

Spittlebug Adults

Mealybugs

Family PseudococcidaeOver 300 species in the USABodies covered with waxy secretionFemales elongate-oval Males resemble gnatsReproduction varies among speciesFound on most parts of an infested plant

Mealybugs

Feeding weakens plantsHoneydew can damage fruit and foliageThree main pest species1. Citrus mealybug2. Citrophilus mealy bugBoth pests of citrus and greenhouses3. Longtailed mealybugA greenhouse pest

Mealybug Lifecycle

Female lays eggs in cottony egg massFirst instar nymph stage or crawlers Not yet covered by waxy secretionsFirst and second stage nymphs resemble

the female Male spins cocoon at end of second

stage – emerges gnat-likeFemale emerges as large waxy covered

adult

Mealybug Lifecycle

Citrus Mealybug

Male citrus mealybug

Female citrus mealybug

Citrus Mealybug

Female citrus mealybug with egg mass

Citrus mealybug infestation

Citrophilus Mealybug

Male Citrophilus mealybug

Female Citrophilus mealybugs

Longtailed Mealybugs

Female longtailed mealybug

Male longtailed mealybug

Ground Pearls

Family MargarodidaeAbout 40 species in North AmericaSome species can reach almost 1” in

lengthSome are root feedersSome pests to citrus and to pines

Ground Pearls

Psyllids

Family PsyllidaeA.K.A jumping plantliceHost-specific plant feedersAdults resemble miniature cicadasStrong jumpersAdults have wings

Psyllids

Nymphs of many species produce waxy secretions – some resembling wooly aphids, others scale

Some species transmit virusSome cause leaf damage

Psyllids

Psyllid eggs

Psyllid nymphs

top & bottom right

Psyllids

Adult Melaleuca Psyllid

Adult Lerp Psyllid

Psyllids

White Lerp Psyllids

Psyllids

Lerp Psyllids

Psyllids

Psyllid Leaf Damage

Woolly Aphids

Woolly aphids exude waxy secretions around their bodies

Family EriosomatidaeSexual form lacks mouthpartsOvipositing female lays only one egg

Woolly Aphids

Some species overwinter on the primary host plant in the egg stage, others pass all generations on one plant

Some species feed on multiple host plants

Feeding occurs on roots or above groundSome species form galls on the primary

host

Woolly Aphids

Woolly Aphid Infestations

Woolly Aphids

Woolly Aphid

Leaf Gall

Woolly Aphid

Root Gall

Woolly Aphids

Ash Woolly Aphid

Elm Woolly Aphid

Cicada

Family CicadidaeTwo common varieties of cicadas

Dog-day cicadaPeriodical cicada

Most damage to plants is caused by egg laying in stems and twigs causing stem dieback

Nymphs feed on roots of mostly herbaceous plants

Some species are on an annual cycle The periodical cicada is on a 13 to 17 year cycle

Dog-Day Cicada

Periodical Cicada

The Cicada That Ate Cincinnati