insect biodiverity E184 module 1

Phylum Arthropoda

bilateria divide into diffrent phyla, diversication called cambreian explosion, arthropods
-jointed appendages

-segmented bodies

-chitin exoskeleton (molted away)
-open circulatory system

What are the sub phyla of hexapods?

Crustacea, Arachnida

Sub phylum- Hexapoda

this is a subphylum of arthropods
-three pairs of jointed legs
-three main body parts (head, abdomen, thorax)
-two antennae

Enthognatha

major class of hexapods
-no flight

-no compound eyes

-ametabolous

Insecta

hexapoda broke off into enthognta and insecta, insecta
-three pairs of jointed legs
-(head abdomen, thorax)
-two antennae (same as hexapods)

+compound eyes,

+wings (sometimes lost)
+metamorphosis (entognatha don’t have this)

Ametabolous

no metamorphosis, from egg as egg hatches and insect develops it grows and grows shedding exoskleton but does not have discrete number of growth stages, sheds throughout it life and all stages are morphologicaly identical

Hemimetabolous

incomplete-fixed number of stages

instars, insect passes through between egg to adult

Nymph stages (first set) differ from adult stage

Everything up to hemimetabolous before adult changes morphologicaly, one most obvious distiniction is that it gains wing, also becomes reproductively mature

Holometabolous

complete metamorphosis( moths and butterflies)
ex. beetle egg up until puppa fully different typically larvae- caterpillar all holometabolis have larval instars, just like hemimetabolist have fixed number of instars, go through complete metamorphosis Adult looks nothing like the larvae

Anterior

nearer the front, towards the head

posterior

further back, nearer hind end

Ventral

relating to belly, located near or toward lower surface of an animal

Dorsal

upper side of an animal, the back

distal (apical)

situated away from the center of the body or point of attachment

proximal (basal)

towards center of body or point of attachment

lateral

of relating to the side

medial

towards the middle center

cuticle

- outer layer beneath this is the epidermis, the epidermis secretes cuticle, cuticle is made of chintin these are long chains of molecules bond to eachother they sclerotize depending on sclerotization it makes it thicker

segmentation and tagmosis

Fundamental to all arthropods, tagmosis combining of multiple segments into fewer segements to make new body parts, ancestral common ancestor have been reduced through tagmosis

head

major body part front, has 6 segments

thorax

three segemnts, middle portion

abdomen

last portion, 11 segements

sutures

each neighboring segment is joined to eachother through sutures

Sclerite

-sclerotized plate anywhere on the body

sclaritized plate in segment and within segment there can be single plate that goes across or there could be more flexible cuticle; which is conjunctival membrane

body types- ametbaolous

egg

nymph (before repoductive age)

adult

this is where adult and nymph are identical, no set number of stages

body types- hemimetabolous

egg

nymph

adult

set number of nymph instars and single adult, adult distinct from nymph (has wings and mature)

body types holometabolous

egg

larvae (immature instars)

puppa

adult ( distinct from immature stages)

head

has the compound eye

ocellus singular visiual organ( more like intensity)

mandible ( sclaritized part used to cut )

palps (used to manipulate food)

antennae

scape- base attach to head

pedicel next segment

flagellum all of following segments can differ from insect to segement

cab end in club thick end flagellum

or have artisa which are spiky parts

if it has a bend then theres a funicle

Thorax

3 segments

prothroax (front)

mesothorax(middle)

methathorax(end)

each of these has legs pair

wings attach to meso or methathorax called ptetorax

spiracles

between segments for respiration tiny holes

sclerities

hard plate on top bottom of all, names for these

on bottom are called sternities

on top are called nota

theres specific one on prothorax called pronotum

scutum- refered to plate on meso and metha

plates also refered to as tergites if drosal top

side plates pleurites

nota specific to thorax

insect legs

segments joined in arthropods parts we should know coxa, base as visble to you, where leg emerges from pluerite, then trochanter it is joint between coxa and femur, after that is tibia then tarsus this can have multiple segments

may end with claws

wings

part of wing two section to know, one are veins these are scleritized rigid part give structure between it are cells these are much much thinner

elytra

in bettle, forwing frontwing, mesothroax are noncell, highly hard scleritized, like ladybug, all bettles that fly, true wings are hindwing, protected by elytra

hemelytra

where half elytra, front half is plate but back has vein and cells, serve some function

haltere

in flies, forwings from mesothroax has base and cells and hindwing shrunk called haltere works like gyroscope helps them navigate and do complex flight

tegmina

forewing is hardned, backwing used for flying, modified forewing used to protect backwing, only used in orthopoera, grasshoper etc

abdomen

last part

tergites and sternites, plate

tergite on top, sternites are on bottom, other sections are spiracles respiartory organs and at tip of apical end theres diffrent structures, cerceus projections and ovaposturs these lay eggs

hexapods

class insecta, enthognata

three pairs of jointed legs

three main body parts (head, abdomen, thorax)

two antennae

class entognatha

differ from insecta as they dont have compund eyes and are ametabolous and missing flight

apterygota (clade)

-archaeognatha and thysanura
-compound eyes

-flightless true insects

-ametabolous

pterygota

-paleoptera, odonata
-wings

-metamorphisis

-all pterygota wings cannot be flexed or laid down over the abdomen

Class Insecta, clades Pterygota > Neoptera (= 10 orders covered):

Wings (sometimes lost)

Wings can be laid down over abdomen

Includes the rest of the Hemimetabola and all of the Holometabola

Class Insecta, clades Pterygota > Neoptera > Holometabola aka Endopterygota (= 7 orders covered):

Wings (sometimes lost)

Wings can be laid down over abdomen

Complete metamorphosis

Collembola (6)

class: entognatha NOT INSECTS!!!!

ex. springtails

ametabolous

-wingless

-no compound eyes

-small soft bodied

-mouthpart inside head

-live in moist leaf litter

-able to propel themselves

Archaeognatha (5)

class: entognatha

ex. bristletails

ametabolous

-unwinged

-head downward

-large protruding eyes -thorax has hump

-cercie shorter than long cotal filament

-nocturnal, ground feeding

Thysanura (3)

class: entognatha

ex. silverfish

apterogyta

ametabolous

-3 long same size tails

-flattened

-feeds on trash

Odonata

class: insecta (pterygota)

ex. dragonfly, damselflies

-toothed

-predatory

-short bristle antennae

large eyes, long engogated body, chewing mouth part, 2 pair wings, net like wings with veins, have pigment cell making stigma, dont hold wing flat to abdomen, stigmata, pterygota, paleoptera, hemimetabola

Dermaptera

neoptra- new winged

derma(skin)- thick skin (tegmina)

key trait - abdomen has forceps like cercie that are not segmented (pincher), just one structure, have tegmina wings, forwing modified

leathery skinwinglike protect hindwing, long slender antane

orthopoera

cricket, grasshopper, hindlegs

enlarged femur for jumping, 2 pairs of wings, have tegmina wings, developed compound eyes, have filiform antennae, chewing mouth part, hemimetabolous

JUMPING LEGS!!!

Phasmatodea

walking sticks, cryptic, hide variable

cryptic flat and wide, long slender, prothorax small, long length due to long meso/metathorax, mostly wingless, obvivorous, mimicry to represent plants

Mantodea

praying mantis, hemimetabolist, small head large antea large eyes, prothorax is elongated, head turns, leg grab things, tegmina (skin like plates to protect hindwings)

*mantis move heads back and forth (confuse predators?)

Blattodea

roaches

flat to ground, pronunced pronotum, plate on top enlarged press on head, long antennae, chewing mouth parts and main morphology, omnivorous, digest cellouse, long antenna, tegmina (forewing)

isoptera

termites, hemimeatbolist, long STRAIGHT anteane, reduced eyes, long mandible, head blockish, winged have two pairs of membranous wings

Psocoptera

Book and Bark Lice, large compound eyes on side of head, head has bolbous look, membarnous wings with few cells, big clear cells, held tent like, chewing mouth, long anteane, 2 pairs of wings*

Pthiraptera

parasitic lice,

wingless

live on host; not move between host much

wingless

eyes are reduced or absent

dorsal ventrally flattened horizontally,

chewing and sucking mouthpart, well developed short legs

Thysanoptera

Thrips, long slender body, elongated head, piercing-sucking mouth (cell content feeders), can also suck, 2 pair feathery wings similar in size, boxy head, large eyes, obivorous

*lives in flowers

hemiptera

KNOW THE SUBORDERS!!!

known as "true bugs"

all have piercing-sucking mouth part

3 suborders: heteroprtra, auchenorrhyncha, sternochyptra

heteroptera (hemiptera subunit)

true bugs

all 3 have 2 pairs of wings, forewing is hemelytra (half elytra, forewing front is hardened), not completely sclerotized, front half hard pronotum enlarged and hemilytera make triangle (scutelum)

MOUTH + TRIANGLE !!!
Predatory

Auchenorrhyncha

(hemiptera subunit)

Cicadas and hoppers, feed solitarility, mobile move alot, wing tent like, pronotoum on top of thoracic segment can be modifed and enlarged

Sternorrhyncha

(hemiptera subunit)

aphids, whiteflies, scale insects (agricultural pests) smaller still hemi, softbodied, obvivorous,

holometabolist

now holometabolist

immature are larvaewhen it goes through pupation reorganizes bpdy, chewing mouthparts, antennea

-neoptera,

Neuroptera (lacewings, antlions)

holometabolist

large eyes

preadtory

chewing mouth parts

elongated prothorax

long antenae

one charcteristic is that they have pincers in larvae stage

however in adult have pretty wings look like fairy, lacewing because many cell

Coleoptera

beetles

key charcteristic have elytra forewing can be fused or beneat it wing

large pronotum

chewing mouth parts

Diptera

holometabolist flies

one pair of wings

forewings only(mesothorax), hindwing made into halteres (metathorax), used to assist with flight

Siphonaptera

fleas, parasitic on birds and mammals, wingless, jumping legs, dorsoventrally flattened, sucking mouthparts, no antennae

Trichoptera

not on test

Caddisflies

look like moth but hairy wings, long antenna longer than wing
mandibles (no proboscis),

Lepidoptera

butterflies and moths

2 pairs of wings covered with scales
curled proboscis

adults only feed on nectar

Hymenoptera

neoptra-holometabolist, ants, bees, wasps, sting, have constricted abdomen, wing joined with hemeli making it look like one wing but are two separate wings, elbowed 90 degree antenne (different from isoptera)