Entom: Chapter 3

Head, Thorax, Abdomen

Insecta’s body division

3 pairs of legs, 2 pairs of wings

adult bear ___________ attached to the thorax and ___________ and attached to the 2nd and 3rd thoracic segment

Veins

Wings with hollow tubes, useful for identification

Mandibulate

(chewing) - Orthoptera, Diptera

Haustellate

(sucking) - Diptera, Hymenoptera

Piercing

Siphonaptera, Diptera

Non-piercing/reduced/non-functional

Hymenoptera and certain Lepidoptera

Nervous system

large ganglion (brain), thoracic and abdominal ganglia, lateral nerve fibers

Large Ganglion

Acts as the brain in the nervous system.

Circulatory system

large dorsal tube (heart) and valves; blood consists of watery fluid (serum or plasma) and white corpuscles w/c are colorless or greenish yellow

Large Dorsal Tube

Acts as the heart in circulatory system

Serum/Plasma

blood consists of watery fluid

Respiratory system

tracheae, tracheoles, spiracles or stigmata

Digestive system

foregut or stomodeum - mouth, pharynx, esophagus, crop /proventriculus; hindgut or proctodeum colon, rectum, anus; midgut or mesenteron - midintestine connects the stomodeum to the proctodeum

foregut or stomodeum

mouth, pharynx, esophagus, crop /proventriculus

hindgut or proctodeum

colon, rectum, anus

midgut or mesenteron

midintestine connects the stomodeum to the proctodeum

Reproductive system

male reproductive system (testes, vas deferens, accessory organ, seminal vesicle, ejaculatory duct, penis or aedeagus; female reproductive system - ovaries, oviduct, vagina, ovipositor, spermatheca (most insects)

Male Reproductive System

testes, vas deferens, accessory organ, seminal vesicle, ejaculatory duct, penis or aedeagus

Female Reproductive System

ovaries, oviduct, vagina, ovipositor, spermatheca (most insects)

Prothorax, Mesothorax, Metathorax

the thorax has three fused segments:

Sclerotized Veins

enclose regions of thin, transparent cuticle called cells.

Cells

The wing if present, consists of a network of sclerotized veins which enclose regions of thin, transparent cuticle called

Vein

acts as a framework to brace and stabilize the wing and carry hemolymph and nerves.

Wing Venation

distinct to each species and is useful for- identification purposes.

DIPTERA

A (Two-winged/True flies)

Haltere

Well-developed anterior wings; posterior wing represented by small club-like organ, which is the organ of balance

Diptera

Wings with hollow Tubes and Veins

Liquid feeders

What kind of feeders are diptera?

Diptera

• complete metamorphosis

• may be parasitic as larvae or adults but are rarely parasitic in both life-cycle stages

Labrum and labium

within which are the mandible and maxilla; in some species, mandibles and maxilla are modified for piercing

Labrum and labium

Composes the haustellum

Haustellum

Sucking tubes for mouthparts adapted for sucking

Nematocera, Brachycera, Cyclorrhapha

Suborders of veterinary importance:

Culicidae, Ceratopogonidae, Psychodidae, Simulidae

Families under Suborder Nematocera

Mosquitos

Family Culicidae

Scales

In culicidae these are present on the head, thorax, abdomen, legs, and wings

Family Culicidae

Slender Insects

Larvae and pupa

In culicidae, these are both aquatic and are active

Plumose

Antennas in Male

Pilose

Antenna in female

Female

blood sucking

Males

subsist on juices of flowers and fruits

Proboscis

consists of the mandibles and maxillae which are the piercing instruments

Labrum

Enclosed in the upper lip

Labium

epipharynx and the lower lip

Labellum

encloses the hypopharynx; the tip of the labium is modified to form the

Mandibles

absent in the male mosquito

Anopheles, Culex, Aedes

Genera of veterinary and medical importance:

A. malicupennis

Anopheles

C. pipiens

Culex

A. aegypti

Aedes

Eggs

laid on the surface of water or on floating vegetable matter

16 - 24 hours

Eggs hatch in this time period into larvae

4 times in 7 days

How many time so the culicidae larva moult?

2-3 days

imago emerges after

2-3 days

sucks blood after 24 hours

Anocepheles Egg

Laid singly with lateral

Culex Egg

Laid in Mass (egg raft)

Aedes eggs

Laid singly without lateral floats

Anopheles larvae

Lies parallel to the water surface; no siphon tube

Culex Larvae

Hangs diagonally from the water surface

Aedes larvae

Hangs diagonally from the water surface

Anopheles Pupae

Short and stout breathing trumpet

Culex and Aedes Pupae

Long and narrow breathing trumpet

Anopheles Palpi

Female palp is as long as the proboscis

Culex and Aedes palpi

Palp of the female is shorter than the proboscis

Anopheles resting

Diagonal against the landing surface

Culex and aedes resting

Parallel to the landing surface

Anopheles Feeding Time

Crepuscular

Culex Feeding Time

Nocturnal

Aedes Feeding Time

Diurnal

15 - 20 days

Life span of mosquito under favorable conditions longer period if otherwise

Wecheraria bancrofti

Culex, Aedes

Dirofilaria immitis

Culex, anopheles

Bacillus thuringiensis

Bacteria to kill larva and pupa

Microsporidia sp

Protozoan parasites