Download GENERAL PROPERTIES OF ARTHROPODS Phylum Arthropoda

GENERAL PROPERTIES OF
ARTHROPODS
Phylum Arthropoda
(jointed feet)
Doç.Dr.Hrisi BAHAR
The arthropods are
● The most successful
phylum of animals, both in
diversity of distribution and
in numbers of species and
individuals.
Arthropoda
● They have adapted
successfully to life in water,
on land and in the air.
● They can survive great
extremes of temperature,
toxicity, acidity and salinity
Arthropoda
● About 80% of all known animal
species belong to the Arthropoda
● About 800,000 species have
been described.
Characteristics of Arthropoda
● Metamerism- body is segmented.
● Exoskeleton- body covered with a
hard
external skeleton.
● Bilateral Symmetry- body can be
divided into two identical halves.
Characteristics of Arthropoda
Jointed Appendages- each segment
may have one pair of appendages,
such as:
● legs
● wings
● mouthparts
Characteristics of Arthropoda
● Open Circulatory System- blood
washes over organs and is not
entirely closed by blood vessels.
Our system is a closed one
● Ventral Nerve Cord- one nerve
cord, similar to our spinal column
Some of the arthropods are
ectoparasite.
Ectoparasite: arthropod living outside the
human body
Some Common Ectoparasites
● Common bedbugs (Cimex lectularius)
● Human fleas (Pulex irritans
Classes of Medical Importance
Subphylum CRUSTACEAE
Two Class are medically
important
● Class Arachnida
● Class Insecta
Class Aracnida
--------------------------------------------------------Mesostigmata Prostigmata
Metastigmata
Ticks
Dermanyssus
Family Ixodidae
Rnithonyssus
Ixodes
Dermacentor
Rhipicephalus,
Haemaphysalis
Family Argasidae
Argas,
Ornithodoros
Mites
Mites
Cheyletiella,
Neotrombicula
Astigmata
Mites
Sarcoptes, Notoedres,
Psoroptes,Tyrophagus,
Tyroglyphus, Glyciphagus,
Dermatophagoides
Class insecta
------------------------------------------------------------------------------------------------
Diptera
Anoplura
(Lice)
Nematosera
(mosquitoes,
black flies)
Cins
Pediculus
Phthirus
Cins
Brachisera
(flies)
Anopheles
Culex
Cins
Aedes
Musca, Glossina,
Simulium
Calliphora,
Phlebotomus
Cochliomyia,Cordylobia,
Lutzomyia
Lucilia, Sarcophaga
Wohlfahrtia,Gasterophilus
Hypoderma,Cuterebra
Heteroptera
(Bugs)
Cins
Cimex
Oeciacus
Triatoma
Rhodnius
Panstrongylus
Siphonaptera
(Fleas)
Cins
Pulex
Ctenocephalides
Ceratophyllus
Archaeopsylla
Xenopsylla
Tunga
Class insecta
● The insects are the
most numerous and
diverse of all the
groups of arthropods.
There are more
species of insects
than species in all the
other classes of animals
combined.
Class insecta
● Insects differ from
other arthropods in
having three pairs of
legs. In size, insects
range from less than 1
mm to 20 cm in length,
the majority being
less than 2.5 cm
long.
Characteristics of Insecta
1- 3 body segments- head, thorax ,
abdomen (stomach area).
2- One pair of antennae
3- Tracheal Respiratory System- composed of
tubes, with holes (spiracles) through the
body that admit air.
● So, they do not have lungs at all.
Characteristics of Insecta
4- Wings- usually two pairs of wings,
although some have one pair of wings,
or none. No other class of arthropods
has wings
5- 3 pair of legs, 1pair to each of the 3
thoracic segments. Compound eyes,
with facets
Order Diptera (Flies)
The larvae of flies.
Flies are common in the warmer months,
and love dead, stinky, and rotting material.
They lay eggs, and the eggs develop into
larvae (maggot) that need to eat. They
appear quite fast (8-12 hours), and will eat
away tissue if the conditions are present
Myasis
Disease that
results from the
infestation of
tissues or
cavities of the
body by
larvae(maggots)
of flies
Anopheles
● Anopheles is a genus of mosquito (Culicidae).
● There are approximately 460 recognised
species: while over 100 can transmit human
malaria, only 30-40 commonly transmit parasites
of the genus Plasmodium that cause malaria
which affects humans in endemic areas.
● Anopheles gambiae is one of the best known,
because of its predominant role in the transmission
of the deadly species –Plasmodium falciparum.
● Some species of Anopheles also can
serve as the vectors for Filariidae
Wuchereria bancrofti
● Mosquitoes in other genera
(Aedes,Culex) can also serve as
vectors of disease agents.
Anopheles gambiae
Culex
Adults of the Cx. Pipiens
complex are light brown
mosquitoes that lack
distinctive markings on
the proboscis and legs,
and are not readily
separated from other
Culex (Culex) mosquitoes.
Adult females of the complex
are usually identified by the
presence of distinctive, basal,
pale abdominal bands.
Phlebotomus (sand flies)
The female sand fly carries the Leishmania
protozoa from infected animals after feeding,
thus transmitting the disease, while the male
feeds on plant nectar.
Phlebotomus species are also vector for
phlebotomus fever, an arbovirus caused by
Toscana virus.
Adults are small
sized about 1.5-3
mm, yellowish
in colour with
conspicuous black
eyes,hairy body,
wings and legs.
Anoplura
(Lice)
• Pediculus
● Pediculus humanus capitis
● Pediculus humanus corporis
• Phthirus
● Phthirus pubis
Lice
Morphology
● Wingless insects.
● Permanent
ectoparasite.
● Host specific
parasites,each lice
species is found on
only a single species
of host.
Pediculus humanus
Pediculus humanus capitis(head louse)
localization and sites of oviposition
Hair on the head, rarely on beard hairs or hairy sites on
upper body.
● Pediculus humanus corporis(body louse)
localization and sites of oviposition
Stitching, seams, and folds in clothes, especially where
it is in direct contact with the body.
Phthirus pubis (crab louse)
localization and sites of oviposition
Hair of pubic area, more rarely in the
abdominal and axillar regions, beard,
eyebrows, and eyelashes.
Order Heteroptera
(Bugs)
Cimex
Cimex lectularius
● They are about 3–4mm long
● Dorsoventrally flattened
bodies
● Greatly reduced wings
● A bloodsucking proboscis
that can be folded back
ventrally
Siphonaptera -Fleas
Pulex
Pulex irritans (Pulex)
• This flea is about 2–5mm long,
● Laterally flattened,
● Wingless
● Have three pairs of legs,
the hindmost of which
are highly adapted for
jumping.
Fleas are competent vectors for numerous
microbial pathogens of medical
and veterinary importance
● Ctenocephalides felis (Cat flea)
Vector of
-Cat scratch disease (Bartonella species)
-Spotted fever (Rickettsia felis)
-Plague (Yersinia pestis)
● Xenopsilla Cheopis(Rat flea)
Vector of
-Plague (Yersinia pestis)
● Pulex irritans(human flea)
Vector of
-Plague (Yersinia pestis)
Class Arachnida
Ticks (Ixodida)
●They are blood-sucking, opportunistic
parasites that can attach to the skin of
a variety of vertebrate hosts.
● They have no segmentation and are
dorso-ventrally flat with four pairs of
legs
Ixodes ricinus
● Vector of the causative agents of Lyme
borreliosis and Tickborne encephalitis
● Human tick bites in central Europe
are in most cases caused by
I. ricinus and only occasionally by
other tick species.
Tick bite
DISEASES FOR WHICH
HARD TICKS ARE CARRIERS
BACTERIAL DISEASES
** Rocky Mountain Spotted Fever
The causative agent,Ricketsia rickettsii,
** Tularemia
The causative agent ,Francisella tularensis
** Q Fever
The causative agent, Coxiella burnetii
DISEASES FOR WHICH
HARD TICKS ARE CARRIERS
BACTERIAL DISEASES
**Human erlichiosis
The causative agent, bacteria of the Ehrlichia
family.
**Lyme Dısease
The causative agent Borrelia burgdorferi (USA)
Borrelia garinii or Borrelia afzelii ( In Europe )
DISEASES FOR WHICH
HARD TICKS ARE CARRIERS
VIRAL DISEASES
** Crimean-Congo Hemorrhagic Fever
The causative agent Nairovirus.
** Tıck -Born Encephalitis
The causative agent,Tick-borne
encephalitis virus
Mites
Sarcoptes scabiei
Causative agent of scabies
Scabies mite (Sarcoptes scabei) is the cause of
scabies and is distributed worldwide. Epidemics
of the disease may occur for long periods but
mites may be common at all times in very poor
communities with inadequate washing facilities.
Sarcoptes scabiei
• Transmission is by close contact (sexual partners,
family,members, school children, healthcare staff)
from person to person,
• Indirect transmission on clothes (underclothes), bed
linens is not a primary route, but should be
considered as a factor in control measures.
• Without a host, mites usually die off within a few
days. Mite infections can also be acquired from
animals to which humans have close skin contact.