ENTM010 Final Study Guide

Adenotrophic viviparity

A reproductive strategy where insects give birth to live larvae that have been nourished internally by specialized glands.

- Fertilize one egg at a time and retain each egg within their uterus to have offspring develop internally

- Female feeds larva from modified uterine gland

- As 3rd instar, larvae leaves uterus and crawls into ground to pupate

- Emerges as adult and now must feed on own for first time

(Each female can produce only 8-10 offspring in her lifetime)

African trypanosomiasis

Also known as sleeping sickness; a parasitic disease transmitted by tsetse flies.

- sleeping sickness

- protozoan pathogen of species Trypanosoma brucei

- invade blood lymph central nervous system -> sleeping disorder

- nagana: animal form of sleeping sickness

Africanized “killer” bees

 A hybrid of African and European honeybees known for aggressive behavior and strong colony defense.

• cross between European honeybee and African honeybee

• known for their increased defensiveness

Almond flower pollination in CA

A crucial ecosystem service where honeybees pollinate California's almond crops, essential for yield.

• European honeybee used for pollination of almond flowers, honey bee hives are brought in from around the US (2 hives per acre), In almond bloom, >80% of all available commercial hives in the US are in CA

Ant antennae

Sensory organs used for detecting chemical signals (pheromones), touch, and environmental cues.

• geniculate antennae / elbow-shaped
  Used to smell, touch, feel, and communicate

  

Ant feeding habit

Varies by species; includes scavenging, farming fungi, or tending to aphids for honeydew.

• omnivorous - eat everything

• milk of aphids and other small Hemiptera, insects and small living or dead invertebrates, as well as the sap of plants and various fruits.

• They also eat insect eggs

• Some are parasitic of other ants

• Many feed mouth to mouth (trophallaxis

• (seed collectors, honeydew drinkers, predators)

Ant-decapitating phorid flies

Parasitoid flies that lay eggs in ants; their larvae decapitate the host as they develop.

• Parasitoids of ants

• Typically Species specific and often caste specific

  

Antlion larva habit

Predatory larvae that dig pit traps in sand to capture and consume ants and other small insects.

• larvae: predator

• require sandy soil/covered with something so they are protected from frequent /divert rain falls

• larvae: build funnel - like trap in sandy soil use to catch insect preys

Aposematic coloration

Bright, warning coloration used by insects to signal toxicity or unpalatability to predators.

• used by noxious organisms to signal their unprofitability to potential predators.

• Bright warning colors in animals with a chemical defense.

Argentine ant biology

An invasive ant species known for forming massive supercolonies and displacing native ants.

• Tend honeydew-producing plant pest: interferes w/ biological control

• Displaces some native arthropods

• Major urban / structural nuisance pest

• Unicoloniality, individuals mix freely among separate nests

• Vast population size / absence of intercolonial aggression in the introduced areas

• similarity in cuticular hydrocarbon signature (colony odors)

• Bite but cannot sting

• Shallow nest in soil under rocks, logs, stepping stones, pavement

Army ant biology

Highly mobile, nomadic ants that form temporary nests and exhibit cooperative predatory behavior.

• Aggressive predatory foraging raids

• Life without a permanent nest: bivouac - making a "nest" with their bodies

• Nomadic phase & Stationary phase: this depends on reproductive cycle of young ants (developmental)

Armyworm

The larval stage of certain moths, known for migrating in large numbers and damaging crops.

• Lepidoptera

• will eat anything in their path

• nocturnal larvae

• undergo seasonal migration

Biting midges

Family Ceratopogonidae (biting midges) aka no-see-ums
- Male and female feed on nectar, but females also feed from some kind of host animal for egg development
- Diverse feeding habit: vertebrate blood, insect hemolymph, etc
- Some are significant vectors of animal disease (ex: bluetongue virus in sheep )

Nonbiting midges

Family Chironomidae (non-biting midges)
- Common nuisance around bodies of water
- Frequently mistaken for mosquitoes (No bite, Wings are shorter than its body, Develops in mud on the bottom of lakes, ponds, Does not carry diseases)

Blackflies

Small, bloodsucking flies; some species transmit diseases like river blindness.

• Buffalo gnat (arched thorax, giving an appearance of miniature bison)

• Females consume nectar and blood while males only feed on nectar

• Bite: female only

• Larvae: aquatic in flowing water

  • Feeding: fan-like labral from -> organic debris in flowing water

  • Attachment: silk -> starve or other substitutes w/ small hooks at end of their bodies

• Adults are long distance flyers: Females in some species will fly several hundred kilometers in search of a blood meal

• Adults are major nuisance pests in upper Midwest, New England and Canada

• In NA, about 6 species are known to bite human

• Pupae: pupate inside of a sunken shelter (cocoon)

• aquatic - "spiracular gill"

Blackfly and disease

Blackflies (genus Simulium) transmit Onchocerca volvulus, the cause of river blindness.

• River blindness (disease): aka onchocerciasis

• Causative agent: microfilariae of a parasitic nematode (Genus Onchocerca)

• Location: Equatorial Africa & Central America

• Causative agent in parasitic nematode

• Nematode enter wound → develop into worm→ mature and migrate through the skinSymptoms = severe itching, bumps under skin

• Treatment: Ivermectin
  

  

Blackfly biology

Females require blood meals to reproduce; larvae live in fast-moving streams.

Blow flies in forensic entomology

Early colonizers of decomposing bodies; their development helps estimate time of death.

• Tend to arrive first to the dead animal's body and lay eggs

• ID species, determine where they are in life cycle then backtrack to get TOD

Bombardier beetle defensive strategy

Releases a hot, chemical spray from its abdomen to deter predators.

• Hydrogen peroxide + Hydroquinone
  chemical gas weapon

Book lung

 A respiratory organ in some arachnids (not insects), composed of stacked, leaf-like structures.

• respiratory organ for subphylum chelicerata (spiders, scorpions)

Cabbage butterfly

A white butterfly (e.g., Pieris rapae) whose larvae are agricultural pests of brassica crops.

• Larvae only feed on / females lay eggs on plants containing glucosinolates

• Defensive compounds characteristic of plant

• Family Brassicaceae (cruciferous vegetables)

• Pests on cabbage and its relatives

Cabbage looper

A green caterpillar known for its looping movement; damages cabbage and related plants.

• Part of Noctuidae family

• The caterpillar larvae are major pests

Caddisfly

Trichoptera

• Related to butterflies & moths (lepidoptera)

• Larvae have various feeding habits depending upon species (larval variability)

• Shredders/scrapers/collectors - larvae mostly feed on periphyton (layer of algae)

California dogface butterfly

The state insect of California; males have a yellow and black pattern resembling a dog’s head.

• only found in California

• wings mimic a dog's face'

• The state insect (CA) since 1972

• Endemic range is limited to the state

• Color and pattern on the underside of wings are simple

Canine heartworm

A parasitic worm (Dirofilaria immitis) transmitted by mosquitoes, affecting dogs' hearts and lungs.

• The Anopheles Mosquito is a vector for this disease.

Cardenolid

A toxic chemical compound found in the milkweed plant that monarch butterflies eat and use against their predators

Carrion beetle

Scavengers that feed on dead animals; some help bury carcasses for their larvae to feed on.

• Coleoptera

• (Family Silphidae) diet: dead animal , colonize carrion during all stages (from early to late) of decomposition, recycling nutrients, chemical defense: excellent deterrent

• aposematic coloration

Casemaking clothes moth

A moth species whose larvae build portable cases from silk and feed on wool or fabric.

• Unique ability to digest keratin

• Damages clothes and carpets

• Pests on animal hair

• Common in southern US, Georgia, and Florida

• Larvae construct cases to hide with various fibers and other materials available in their habitats

• Adult has 3 dark spots on wings
  Larvae: pest on fabrics, prefer fabric that is old / contaminated

• Larvae carry case. If separated, they will die. As the larvae grow, they lengthen the case by building onto old case at each molt.

Characteristics of Insecta

Three body segments (head, thorax, abdomen), three pairs of legs, exoskeleton, and typically wings and antennae.

• 3 tagmata (head, thorax, abdomen)

• wings: 2 pairs (always found in thorax)

• compound eyes

• 1 pair of antennae

• 3 pairs of jointed legs

• various mouthparts

Characteristics of Lepidoptera

Insects with scaled wings; includes butterflies and moths, undergoing complete metamorphosis.

• siphoning mouthparts

• proboscis

• wings have scales

• scales = modified hairs

• larvae feed on plants

• larvae spins silk

• greatest color variation

• major agricultural pests

• Larvae have six true legs on thorax, plus abdominal and anal prolegs

• adults feed on nectar

Cochineal

A scale insect used historically and commercially for producing carmine red dye.

• Sessile parasites on plants

• Lives on cacti in genus Opuntia

• Natural dye carmine is derived

Colorado Potato Beetle

A major pest of potato crops; resistant to many insecticides.

• Leaf Beetles (Family Chrysomelidae)

• Major Crop pests

• feed on several different plants within nightshade family

• Quickly develops resistance to insecticides

Corixidae respiration

Water boatmen breathe through air stores held on their bodies and come to the surface to replenish them.

• Lack gills, carry air bubble down into the water to take oxygen from water

Crane fly biology

Harmless, long-legged flies; larvae live in moist soil or water and feed on decaying organic matter.

• Stilt-like legs may be easily shed (defensive mechanism)

• Larvae are important soil engineers and either aquatic/terrestrial

• Active during spring, after the rain, and at night

• Emerges from the soil, flies low to mate and lay eggs

• Lays eggs in the ground, the larva stays in the soul and looks like a maggot

• Has halteres

Cryptic coloration

Camouflage that helps insects blend into their environment to avoid predation.

• Camouflage; makes an organism difficult to spot.

Dance language of honeybee

A method of communication using movements to inform others about food sources.

• wobble or waggle dance to tell other bees direction & distance to the food source (nectar, pollen)

• The foragers that return from flower sources

Darkling beetle feeding habit

Scavengers; eat both fresh and decaying vegetation. 

• Feed on dried or rotting plant matter. In captivity, they feed on bran meal, apples, oranges, potatoes, cucumber, romaine lettuce, and pears. Remove uneaten food before it molds

• Order Coleoptera

• Fused Elytra

• Flightless

Diapause

A type of dormancy in insects that is associated with a period of unfavorable environmental conditions.

Disease and body louse

Lice (Pediculus humanus corporis) transmit diseases like typhus and trench fever.

• Human body lice transmits epidemic typhus fever

• bacteria: rickettsia

• develop off human body

Diversity in insects

~1M named insect species, 1.9 million total species

• Based on the number of known species (all animals, all plants, all virus, all bacteria, all fungi...), of the approximately 1.9 million presently recognized, just over half are insects.

Diving beetle feeding habit

Predatory aquatic beetles; larvae and adults feed on small aquatic organisms.

• predaceous

• air bubble + natatorial legs

Dung beetle biology

Beetles that use dung as a food source or to lay eggs; important for nutrient recycling.

• (Family Scarabaeidae): Adults eat soft dung

• rollers & tunnelers & dwellers

• Dung as provision for: developing larvae

• Recyclers of animal dung

• associated with Re, supreme being and sun god in Egyptian culture

Ecdysone

A hormone that promotes molting and the metamorphosis of a larva to a butterfly.

Ecological advantages of dipteran insects

Includes pollination, decomposition, disease vectoring, and as a food source.

• Separate niches for life stages

• Adults dispersal ability: Some black flies travel > 100 km!

• Larvae specialize in rotting organic materials

• Short generation times for many species (7-10 days)

Ephemeroptera

Order of insects known as mayflies; have short adult lives and aquatic nymph stages.

• Hemimetabolous, yet has two stages (subimago and imago) after nymphal stage

• Unique to only this order and fairly dies shortly after becoming an adult. large triangular wing, 1 caudal filament & 2 cerci. adult terrestrial, nymphs aquatic.

Epidemic Typhus Fever

Transmission of disease by human body lice

• Caused by bacterium Rickettsia prowazekii

• Symptom: sudden headache, chills, high fever, protration, coughing and severe muscular pain, skin rash

• Typically occurs in conditions of overcrowding and poor hygiene aka prisons and refugee camps

• Common in concentration camps in WWII

Etymology of Hymenoptera

Derived from Greek: “hymen” (membrane) + “ptera” (wings); includes bees, ants, wasps.

• > 150,000 recognized species

• Evolved ~ 250MYA

• Diverse order!

• Complete metamorphosis

Etymology of Lepidoptera

Greek origin: “lepido” (scale) + “ptera” (wings); refers to butterflies and moths.

• butterflies and moths, "lepidpo" = scale, "ptera" = wing

Eusociality

Social organization with cooperative brood care, division of labor, and overlapping generations.

• Live in groups as adults

• Cooperative brood care

• Reproductive division of labor

• Overlapping generation in adults

Evolution of hexapods

Hexapods evolved from crustacean ancestors; includes all six-legged arthropods like insects.

• class Entognatha- may be polyphyletic and have internal mouth parts.

• Protura: cone headed soil organisms.

• Diplura: two-pronged bristletails.

• Collembola: springtails.

• Furcula: "jumping fork"

Fire ant adaptation

Aggressive behavior, venomous sting, and the ability to form floating rafts during floods.

• Seed harvesting (like harvester ants)

Firefly bioluminescent organ

 A light-producing structure in the abdomen, used for mating communication.

• Luminescent organ on abdomen

• Involves specialized cells, photocytes [responsible for producing light]

• Luciferin, luciferase, energy, oxygen

• Highly efficient [no heat created, energy goes into light production]

• Lights used to attract mates [adults]

Fly response to a corpse

Flies rapidly colonize decomposing bodies; species appear in predictable succession.

• Tend to arrive first to the dead animal's body and lay eggs

Foraging strategies in Myrmicinae

Myrmicine ants show diverse foraging: trail following, group foraging, and solitary hunting.

• seed harvesting and fungus growing

Forensic entomology

Study of insects in legal contexts, especially for determining postmortem intervals. (TOD)

Formic acid

A defensive chemical secreted by many ants, especially formicines.

Function of Malpighian tubules

Excretory organs in insects that remove nitrogenous waste and regulate water balance.

• Main excretory organs in most insects. 

• Key role in the production of primary urine and osmoregulation, selectively reabsorbing water, ions, and solutes.

• Filters hemolymph of metabolic wastes and transfer wastes to hindgut - comparable to kidney

Glucosinolates

Plant defensive chemicals; some insects sequester them to deter predators.

• Larvae only feed on / females lay eggs on plants containing glucosinolates of cabbage butterfly

• Defensive compounds characteristic of plant

• Family Brassicaceae (cruciferous vegetables)

Gossamer-winged butterfly

A family (Lycaenidae) of small, delicate butterflies including blues, coppers, and hairstreaks.

• small, less colorful

• phytophagous or entomophagous (insect-feeding)

• 75% engage in an association with ant (some are parasitic)

Gulf fritillary

A butterfly with orange and silver markings; its larvae feed on passionflower vines.

• Agraulis vanillae

• Species of butterflies from Family Nymphalidae (brush-footed butterflies)

• Bright orange, long narrow wings

• family: nymphalida

• eorder: lepidoptera

• largest family of butterflies

• larvae have defensive spikes on body

“Hair-pencils” in butterfly

Tufts of scent-emitting scales used in courtship by some male butterflies.

Haltere

Modified hindwings in flies used for balance during flight.

• Small knob-like structure that exists behind each wing of flies and their relatives; function in stabilization during flight.

Hamulate wing-coupling mechanism

Tiny hooks on hindwings that latch onto forewings in Hymenoptera for synchronized flight.

Harvester ant

Ant species that collect, harvest, and store seeds; some are important for soil health and seed dispersal.

Hemolymph functions

Insect blood; circulates nutrients, hormones, and immune cells but does not carry oxygen.

• used by invertebrates to deliver nutrients, transport materials, and remove waste.

• Without hemolymph, the tissues and cells of these invertebrates would not be able to perform their intended functions, nor remove waste materials as they are produced.

Holometabolous

Complete metamorphosis with four life stages: egg, larva, pupa, adult.

Hornet

A large, social wasp known for powerful stings and aggressive nest defense.

• Nesting: on trees

• Diet: aggressively hunt bee hives

Hornworm

The larva of hawk moths; major pests of tomato and tobacco plants.

• larvae of Tomato horn worm (Manduca quinquemaculata)

• Major pests of tomatoes especially for organic gardeners (also potato, pepper, eggplant, tobacco - all members of nightshade family)

• Cryptic but we can use UV to find them on host plants

Horsefly feeding

Female horseflies feed on blood; males feed on nectar.

• Adults: stout bodied powerful fliers w/ large eyes and excellent vision/both sexes feed on nectars

• Females use knife-like mandibles and maxillae to make an incision and then lap up the blood from the pool

Hydroquinone

A chemical involved in the bombardier beetle’s explosive defense.

Hymenoptera biology

• Ants, bees, and wasps

• complete metamorphosis

• 2 pairs of wings (hamulate- hooks) and compound eyes

• chewing and lapping mouthparts

• stingers (modified ovipositor)

• larvae pupate in apocrita

Hymenoptera sex determination

Haplodiploid system: fertilized eggs become females, unfertilized become males.

• females develop from fertilized eggs while males develop from unfertilized eggs

• Females can reproduce haploid males without mating

Japanese beetle feeding habit

Adults feed on foliage and fruits of many fruiting trees and shrubs. 

Jewel beetle characteristics

Family buprestidae

• description = texture cuticle, shiny/metallic, thin film interference

• diet = wood of trees-some are pryphils, organs sensitive to radiations

• can detect radiation from heat and fires; forest fires

Larvae and adults in Diptera

Undergo complete metamorphosis; larvae often live in different habitats than adults.

• No legs, sometimes spines diurnal , active but some are nocturnal or crepuscular (active at dusk or dawn)

• larvae stay in or around their food source
  primitive flies- caliciform type larvae (presence of distinct head capsule)

• vermiform type larvae- maggots (without head capsule reduced to hooks)

• Halteres: gyroscope (excellent aeralists)

Leaf beetle

Herbivorous beetles that feed on leaves; includes pests like the Colorado potato beetle.

• (Family Chrysomelidae)

• Major Crop pests

• feed on several different plants within nightshade family

• Quickly develops resistance to insecticides

Leaf-cutter bee

Solitary bees that cut leaves to line their nests; important pollinators.

• Uses hollow stems of plants, holes in solid wood, other protected natural cavities

• Semi-domesticated (live in man-made nests (easy to domesticate)

• have a tuft of hair on the abdomen used to collect pollen (scopae)

Leafcutter ant biology

Ants that farm fungus on cut leaves in underground colonies; highly social.

• Unique farming of fungus. They collect leaf(leaves) to serve as the nutritional substrate of their fungus

• Constantly taking out pathogenic fungus or molds & also produce antimicrobial compounds

Leishmaniasis

A disease caused by Leishmania parasites, transmitted by sandflies.

• vector: sandfly

• 40 diff sand fly species (vector)

• 20 diff protozoan parasite species

• very specific vector/parasite combo

• Cutaneous (most common), visceral, mucocutaneous

• Risk factors: malnutrition, poor hygiene, poverty, urbanization, deforestation

• Prevention: sleep under mosquito nets treated with insecticide

• Treatment: depends on the species parasite and where contracted

• occur in US military

Lycaenidae biology

Small butterflies often associated with ants; some larvae are carnivorous.

• gossamer-winged butterflies

• small in body size and less colorful than other families

• diverse in their food habits: phytophagy, entomophagy

• (75%) larvae associated with ants
  master manipulators = nest parasitism

Maggot therapy

Use of fly larvae to clean necrotic tissue from wounds.

• use of larvae of a species of blow flies that secrete an enzyme that dissolves dead tissue

• Debridement: removal of dead, damaged, or infected tissues to improve healing potential of remaining healthy tissue

• Disinfection - secrete several different compounds that have broad-spectrum antimicrobial activity (uric acid, allantoin, ammonia; antibacterial peptide)

Mayfly characteristics

• Adults do not feed, only disperse, mate, and die

• Large triangular front wings

• 1 median caudal filament and 2 cerci (long)

• Adults terrestrial, nymphs aquatic (respire thru abdominal gills)

• Relatively long life cycles (live as nymphs for months to years)

• Subimago stage

• final stage before molting to adult (imago)

• Mass emergence swarms, lay eggs in water

• Very important in food webs

Medico-legal forensic entomology

This is the study of how insects or their remains are used in the investigations of death, abuse, criminal, and neglect cases.

Mimicry

Imitation of one species by another for protection

• "Classic" Mimicry: An insect blends in with its surroundings. Ex. Leaf insects, stick insects

• Batesian mimicry: An unprotected species (mimic) evolves to look like a protected species (model)
  ex: Coral Snake (venomous ) & Milk snake (non-venomous)

• Mullerian Mimicry: A chemically protected species (mimetic #1) evolves to look like another protected species (mimetic #2)

Mosquito and diseases

Mosquitoes transmit diseases like malaria, dengue, Zika, and West Nile virus.

• Culex Mosquito: Disease Vector for West Nile Virus (WNV)

• Aedes Mosquito: Disease Vector for Dengue, Yellow Fever, WNV, and Zika

• Anopheles Mosquito: Vector for Mammalian Malaria and Canine Heartworm

Moths vs. butterflies

• Moth: feather like (bipectinate) or thin antennae, Cocoon (silken case surrounding pupa), body robust, wings flat at rest, often nocturnal

• Butterflies: Thicker antennae with bulbs or hooks on end

• Chrysalis (is the pupa, with hardened protein exoskeleton as outer protection), body thinner, wings upright at rest, diurnal

Natatorial leg

 A leg adapted for swimming, often flattened and fringed with hairs.

Nesting habits in wasps

• new nest every year and is constructed out of wasp paper made by chewing wood and other plant debris mixed with saliva

• no wax producing gland

• Wasps lay eggs in caterpillars' body

• As eggs hatch, they feed on caterpillars' internal organs

• When ready to pupate, larvae emerge and spin cocoon on the
  surface of the hornworm

• From these cocoons, new wasps will emerge

Neuropteran feeding habit

• Lacewings (family Chrysopidae) and antlions (family Myrmeleontidae), are predatory and feed on other insects

• Mantispids (family Mantispidae), feed on nectar and pollen as adults

Nymphalidae leg

• Adults have reduced forelegs

• stand only on 4 legs while the other two are curled up

Ocelli

Simple eyes on an insect used to sense light

Ommatidia

Light sensing units of compound eyes; each contributes to an insect’s mosaic vision.

Onychophora characteristics

Velvet worms; segmented, soft-bodied, terrestrial, and closely related to arthropods.

• Bilaterally symmetrical

• Gas exchange via trachea

• Open circ system

• Exoskeleton

• Link between worms and arthropods

• velvet/walking worm

Osmeterium

A gland in swallowtail caterpillars that emits foul odorous chemicals as a defense.

• "Smelly horn" (chemical defense)

Parasitoid vs. predators

Parasitoids kill hosts slowly from within; predators kill multiple prey directly.

• parasitoid: needs only one host to complete life cycle

• predator: needs a lot of prey to complete one life cycle

Pentatomidae characteristics

Stink bugs; shield-shaped body and foul-smelling defense chemicals.

• Shield and Stink bugs

• Distinct angular shape

• Brightly colored

• Noxious odors (hence stink bugs!)

• Some are agricultural pests

  

Pheromones

Chemical signals released by an animal that communicate information and affect the behavior of other animals of the same species.

Phorid flies and ants

Includes ant-decapitating species; also associated with decaying matter.

• some are parasitoids of ants and can be used in biocontrol

• ant decapitating (lay eggs on ants thorax → larvae migrate to the ant's head and feed on hemolymph, muscle, and nerve tissue

• family formicidae

• ants are eusocial (small workers- nurses, medium workers- colony maintenance and foraging, large workers- soldier)

Pollen basket

A structure on honeybee legs used to carry pollen back to the hive.

• on hind leg tibia of European honey bee

Problems caused by invasive ants

Disrupt ecosystems, harm native species, damage electronics, and pose health risks.

• threaten ecosystem stability = generate significant environmental and economic cost

• threaten biodiversity, spread disease

• alter stability and quality of ecosystem processes