Cockroaches - Med/Vet Exam 2

Ametabolous Development

• Wingless adults

• Size is only difference between stages

Simple (incomplete) metamorphosis

• Wings develop externally

• No quiescent stage

• Young are called nymphs

Complete metamorphosis

– Wings develop internally

– Quiescent stage = pupal

– Egg, larva, pupa, adult

Simple and Complete Metamorphosis Difference

Simple: Adults and immatures can have same diet Compete for the same food and space.

Complete: Adults and immatures have very different diets

Cockroach External Anatomy: Shape, Wings, Antenna Shape, Head, Mouthparts

Shape: Dorsoventrally Flattened

Wings: Leathery, Tegmina
Antennae: Long Filiform
Head: Tucked enlarged Pronotum
Mouthparts: Mandibles

Cockroach Life Cycle

Simple Metamorphosis

What is a cockroach egg sack

Ootheca

What happens when there are too many cockroaches in one spot

They produce aggregation pheromones

What do aggregation pheromones do?

reduces locomotory response

– Pros: Decreases nymphal development time

– Cons: Adults will be smaller in size and at risk of cannibalism

Cockroach Habitat & Behaviors

– Majority of species are tropical/subtropical

– Nocturnal though some will be attracted to lights

Are most cockroach species domestic, peridomestic, or feral

Feral - Only 2 species are domestic, Only 6 are peridomestic

Where are cockroaches found? Domestic and Peridomestic

Domestic: Need moisture are found around kitchen, and secondarily around bathrooms

Peridomestic: Require high moisture so are found is septic tanks and sewer system

Coackroaches Diet

Omnivorous, ( eat books, wallpaper, blood, excreta, dead insects, skin, )can survive weeks w/o water and food.

Are cockroaches disease vectors?

Not known to be

Are cockroaches a source of allergies?

Yes! Significant source of indoor allergies.

What type of vector would a cockroach be considered?

Mechanical. Blamed because of presence around food and waste.
Evidence: Cockroaches established as a vector of Hepatitis B

What type of host would a cockroach be to nematodes?

Intermediate host of nematodes.