ENTM 100 Review

Flashcards for vocabulary review.

Trichoform sensilla

Hair-like structures (setae) innervated by neurons that detect touch; found near joints, legs, and behind the head.

Campaniform sensilla

Flattened discs responding to bending in the exoskeleton; found on legs, wing bases, and sutures.

Chordotonal Organs

Sensory units (scolopidia) for detecting internal body vibrations; found in joints, antennae, and legs.

Subgenual organs

Detect substrate vibrations; located in legs.

Tympanal organs

Detect airborne sound; "ears" located on thorax, abdomen, or tibia.

Johnston’s organ

Located in antenna pedicel; senses movement and sound (especially in mosquitoes and midges).

Stridulation

Rubbing a scraper against a file (common in crickets).

Tymbals

Drum-like membranes in cicadas and other insects.

Gustatory

Detected via sensilla on mouthparts, ovipositor, and tarsi; respond to water-soluble substances

Olfactory

Detected via antennal sensilla; respond to airborne molecules at low concentrations.

Uniporous

Single pore for taste

Multiporous

Multiple pores for smell (e.g., moths can detect sex pheromones from miles away; Luna moth has ~45 million pores).

Pheromones

Used for intraspecific communication.

Allelochemicals

Interspecific (different species) communication

Kairomones

Benefit receiver (e.g., parasite detecting host odor)

Allomones

Benefit sender (e.g., beetle sprays a repellent)

Synomones

Benefit both sender and receiver (e.g., plants attract parasitoids of their herbivores)

Dermal Detection

Basic light sensing through cuticle.

Stemmata

Simple eyes in larvae, detect light intensity.

Ocelli

Detect light levels and horizon, not image-forming.

Compound Eyes

Made of ommatidia; detect light and motion; poor binocular vision but wide field of view

Kinesis

Random movement affected by stimulus intensity (non-directional).

Taxis

Directed movement toward/away from stimulus.

Anemotaxis

Air

Phototaxis

Light

Chemotaxis

Smell/taste

Geotaxis

Gravity

Phonotaxis

Sound

Thermotaxis

Temperature

Asexual Reproduction (Parthenogenesis)

Offspring arise from unfertilized eggs; involves only females.

Sexual Reproduction

Involves males and females.

Spermatophores (SP)

Sperm packets with spermatophylax (non-sperm protein for nutrition) and sperm ampulla (contains the sperm).

Aedeagus

Male copulatory organ composed of phallobase and endopallus.

Traumatic Insemination

Males pierce the female’s body wall to inject sperm into hemolymph (e.g., bedbugs).

Sperm precedence

Last male often fertilizes the most eggs

Oviparity

Egg-laying

Ootheca

Protective egg case.

Viviparity

Live birth

Ovoviviparity

Eggs hatch inside the female.

Pseudoplacental

Female provides nutrients via placenta-like tissue.

Haemocoelous

Embryos develop in hemolymph.

Adenotrophic

Larvae feed from female's “milk” gland (e.g., tsetse flies).

Parthenogenesis (Thelytoky)

No fertilization; female offspring (e.g., aphids).

Arrhenotoky

Male offspring (e.g., Hymenoptera).

Deuterotoky

Both sexes.

Pseudo-arrhenotoky

Paternal genome eliminated (e.g., mealybugs).

Polyembryony

One fertilized egg → many identical offspring (e.g., parasitic wasps).

Paedogenesis

Larvae reproduce (e.g., gall midges).

Hermaphroditism

Rare; individual has both sexes (ovotestis).

Endosymbiont influence: Wolbachia

Manipulates sex and reproduction.

Ametabolous

No Metamorphosis

Hemimetabolous

Incomplete Metamorphosis

Holometabolous

Complete Metamorphosis

Polypod

With prolegs

Oligopod

No prolegs

Apod

No legs

Instar

Form between molts

Stadium

Time between molts

Voltinism

Number of generations per year

Univoltine

1 gen/year

Bivoltine

2 gens/year

Multivoltine

Many gens/year

Quiescence

Temporary developmental halt, resumes with favorable conditions

Diapause

Developmental pause needing specific stimuli (seasonal adaptation)

Aestivation

Summer dormancy

Diapause

Winter dormancy

poikilothermic

body temp and development depend on environment

Taxonomy

Naming, describing, and classifying species

Phylogenetics

Studying evolutionary relationships

Species Delimitation

Defining boundaries between species

Morphological Species Concept

Based on physical characteristics

Biological Species Concept (Ernst Mayr)

Groups of interbreeding populations reproductively isolated from others

Synapomorphy

Shared derived traits indicating close relations

Plesiomorphy

Ancestral traits (less informative)

Parsimony

Simplest tree with fewest evolutionary changes

Likelihood/Bayesian

Use probabilities/statistics to infer relationships

Detritivores (saprophages)

Consume decaying organic matter, produce frass (insect poop)

Wood Decomposers

Ambrosia beetles

Coprophagous insects

Dung feeders

Necrophagous insects

Carcass feeders

Mycophages

Fungivores

Troglobitic Insects

Cave insects (cavernicolous)

Black Soldier Fly

Used for biowaste treatment due to efficient organic matter breakdown

Ephemeroptera (Mayflies)

Always aquatic in immature stage

Odonata (Dragonflies, Damselflies)

Always aquatic in immature stage

Plecoptera (Stoneflies)

Always aquatic in immature stage

Trichoptera (Caddisflies)

Always aquatic in immature stage

Naiads

Aquatic nymphs

Halobates spp.

Air

Marine water strider genus

only known insects living on open ocean surface

Phytophagous

Plant-feeding insects

Monophagous

feeds on one plant species (highly specialized)

Oligophagous

feeds on a few related taxa

Polyphagous

generalists feeding on many plant taxa

Pairwise (Specific) Coevolution

one insect species and one plant species adapt reciprocally

Diffuse (Guild) Coevolution

groups of insects and plants adapt to one another over time in a more general fashion

Constitutive defenses

always present

Induced defenses

triggered by herbivory

Gall Inducing

Stimulate plant growth to form protective structures (galls)

Myrmecochory

seed dispersal by ants