Entomology for Master Gardeners. David J. Shetlar, Ph.D. The “BugDoc”. The Ohio State University, OARDC & OSU Extension Columbus, OH. © January, 2009, D.J. Shetlar, all rights reserved. What is Entomology?. The study of insects (and their near relatives). What are insects
Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.
for Master Gardeners
David J. Shetlar, Ph.D.
The Ohio State University,
OARDC & OSU Extension
© January, 2009, D.J. Shetlar, all rights reserved
The study of insects
(and their near relatives).
What are insects
(and near relatives)?
Insects and their relatives are
(classifying & naming)
Genus & species
Kingdom - Animalae
Phylum - Arthropoda
Class - Hexapoda (=Insecta)
Order - Coleoptera
Family - Scarabaeidae
Genus - Popillia
Genus & species -
(>15,000 species, all trophic areas)
(9,000 species, all trophic areas)
Snails/Slugs, Clams, Cephalopods
(50,000 species, aquatic and terrestrial)
Urocordata, Cephalocordata, Vertebrata
The arthropods are divided into two large groups that exist today:
Class Xiphosura – horseshoe crabs
Class Arachnica – arachnids
Class Crustacea – crustaceans
Class Diplopoda – millipedes
Class Chilopoda – centipedes
Class Symphyla – garden centipedes
Class Hexapoda – insects
Blacklegged (deer) tick female
Twospotted spider mites
(many legged arthropods)
(all have one pair of antennae, a head region, and trunk with many pairs of legs, use trachea)
[one pair of antennae, head & trunk regions, trunk with many pairs of legs]
Two pair of legs per visible segment, attached under body.
Pair of fangs under head, one pair legs per visible segment - attached to side of body.
No fangs, no eyes, legs attached to side of body.
Garden centipede (Symphyla)
(mostly marine, fresh water, a few terrestrial)
(all have two pair of antennae, five or more pairs of legs, segmented abdominal appendages, head & trunk or cephalothorax & abdomen body arrangement, have gills)
Cana lily skipper (a butterfly) larvae have an almost completely transparent exoskeleton, thereby allowing a good view of the tracheal system.
(hairy chinch bug)
egg 1st 2nd 3rd 4th 5th normal wing short wing
instar instar instar instar instar adult adult
Egg Nymphal Adult
Stage Stage Stage
Egg Larval Pupal Adult
Stage Stage Stage Stage
Complete Metamorphosis Example
(northern masked chafer)
egg 1st 2nd 3rd pupa adult
instar instar instar
Entognathous Hexapods –
Ectognathous apterygote Hexapods –
Pterygote Hexapods –
(simple metamorphosis cont’d)
Head louse nit (egg)