Arthropoda Flashcards
Hemocoel
Main body cavity of arthropods
Similarities between Arthropods and Annelida
Metamerism (segmentation)
NS consisting of supraesophageal ganglia, nerves encircling the esophagus, and a ventral series of segmental ganglia
Pygidium
Terminal/hind segment of body
Chelicera
Pair of appendages in front of the mouth, usually modified as pincerlike claws
Palps
Each of elongated segmented appendages near the mouth of an arthropod, usually concerned with the senses of touch and taste
Argulus sp
Branchiuran fish louse
Reduced mouthparts (piercing “proboscis”)
Has suction cups to hold onto the host (ectoparasites)
2 prominent movable compound eyes are visible in head region
4 pairs of thoracic swimming legs
Feed by inserting digestive enzymes into body, then sucking out liquidized host
Symptoms: inflammation, skin ulcer, gill diseases
Treatments: Emamectin benzoate, dimilin, baths
3 subphylums of Arthropoda
- Crustacea (copepods, barnacles & relatives)
- Chelicerata (ticks and mites)
- Atelocerata (flies, bugs, lice, fleas)
Micropredators
Temporary parasite
Can transmit disease and drink our blood
Do not stay on one host for their entire life
Specialized to find a capillary, specialized mouthparts, secrete anticoagulant and anaesthetic
4 families in class copepoda
- Family Lernaediae (anchor worms)
- Family Ergasilidae (gill lice)
- Family Caligidae (sea lice)
- Family Pennellidae
Difference between D. andersoni larva and nymphs
Larva have 3 pairs of legs, nymphs have 4
Sarcoptes scabiei (lab)
Itch mite
Definitive host is humans, and wild/domesticated dogs and cats
Cause mange
Ectoparasites
Demodex follicularum mite
Face mite
Humans are definitive hosts
When found in large number they cause demodicosis
Usually found in human hair follicle
Uniramous appedanges vis biramous appendages
Uni: not branching, only 1 function (subphylum chelicerata)
Bi: branched with 2 functions (1 is locomotion, other is grooming, etc) - crustaceans
Amblyomma americanum
Lone star tick
Diseases: Rocky Mountain Spotted fever, tularemia
3 hosts (larva, nymph, adult) - need 3 blood meals to develop to adult stage
All stages can feed on humans
Rocky Mountain Spotted fever (agent, symptoms, treatment)
Agent: Ricketsia rickettsii
Symptoms: Rash resulting from the leakage of blood vessels, nausea, appetite-loss, fever, myalgia, headache
Treatment: Antibiotics (doxycyline)
Tularemia
Agent: Francisella tularensis
Highly infectious
Symptoms: swollen lymph glands, skin ulcers, inflammation of eyes/throat, diarrhea
Treatment: Antibiotics (streptomycin, gentamycin, tetracyclines)
Boophilus microplus
Different than Boophilus annalutus
Disease: Babesiosis, Anaplasmosis
Single host (3 blood meals)
Cattle is preferred host
Dermacentor sp.
Disease: Rocky Mountain spotted fever, tularemia, tick paralysis
3 hosts (dogs are favorite of adults)
Posterior is pale in females
Ixodes scapularis
Black-legged or Deer tick Much smaller than Dermacentor Disease: lyme, tick encephalitis 3 hosts (deer is preferred host of the adults) Posterior end is dark in females
Lyme disease (agent, symptoms, treatment)
Agent: Borrelia burgdorferi
Symptoms: Erythema migrans, pain in joints/limbs, fatigue, headache, neck pain
Treatments: Antibiotics (doxycycline)
Tick-borne encephalitis (agent, symptoms, treatment)
Agent: virus of the family Flaviviridae
Symptoms: 1. Fever, anorexia, headaches, nausea/vomiting 2. Attack CNS
Treatment: Hospitalization and supportive care based on syndrome severity
Tick-borne relapsing fever
agent, symptoms, treatment, long term after effects, carried by
Agent: spirochetes of the genus Borrelia
Symptoms: recurring episodes of fever, nausea, anorexia, headaches
Treatment: Antibiotics
Long-term after-effects: cardiac/renal disturbance, ophthlamia, abortion
Carried by: Ornithodoros turicata (soft tick)
Hard vs soft ticks:
- Capitulum
- Shield
- Life Cycle
- Feeding
Hard ticks:
1. Apparent and easily identified from above
2. Dorsal shield of scutum of sclerotized cuticle
3. 3 distinct life stages: larva, nymph, adult
4. Feed only 1X in each stage (prior molting)
Soft Ticks:
1. Not apparent from above
2. No scutum
3. Several molts in nymph stage prior reaching adulthood
4. Feed several times in each life stage
Pediculus humanus corpis
Body louse More elongate than Phthirus Head bearing short antennae Thorax with 3 pairs of legs Oval abdomen Wingless
Phthirus pubis
Crab louse
Thorax with 3 pairs of legs (first pair is slender compared to other 2 (which have single claws)
Broad abdomen
Wingless
Female sometimes shows developing egg in body
Haemotopinus suis
Swine and cattle louse
Head, thorax and abdomen are dorso-ventrally flattened
3 pairs of strong legs each with a claw
Antennae extended laterally from head - 5 segments
Wingless
Narrow, pointed hear with recessed stylets (adapted for sucking)
Cimex lectularius
Human beg bug Dorso-ventrally flattened, somewhat oval, wingless Basic body plan: head, thorax, abdomen 3 pairs of jointed legs Single pair of antennae
Pulex irritans
Flea- human head or body louse
Bilaterally compressed body, stout clawed legs for jumping
Haustellate or piercing/sucking mouthparts in adults
2 lateral ocelli or 2 simple eyes
Short, 3 segmented antennae in groove on side of head
Wingless
Terminal area of male is modified with a pair of 2 segmented claspers
Culex sp.
Mosquito
Larva is long and narrow with more than one pair of subventral tufts
Male has antennae with more bristles extending from the central axis of the organ
Female only has a few bristles at each joint of the central axis
Melophagus ovinus
The sheep ked - fly that doesnt fly!
Notoedres cati
Suborder Astigmata
Primary cause of mange in cats (face mange or notoedric mange)
Infection begins at tips of ears and progresses over face and then to body
Sarcoptes scabiei (lecture)
Scabies mites
Transmission occurs by contact - highly contagious
Mites burrow into the upper layer of the skin to deposit eggs
Larvae escape the tunnel, wander on the skin, and start new burrows (use ink to see)
Sarcoptes scabiei symptoms, diagnosis, treatment
Symptoms: rash, scabies hitch (nocturnal), septic pustules
Diagnosis: ink on skin, microscopic examination of skin scraping
Treatment: Scabicide applied to before bed to whole body (Permethrin cream), also Ivermectin and sulphur preperations
Norwegian scabies
Same as sarcoptes scabiei but much worse
Demodex spp
suborder, 2 species
Suborder Prostigmata
Infects many species of mammals, high degree of host specificity
1. D. folliculorum (hair follicules)
2. D. brevis (sebaceous glands)
Demodex canis
Dog follicle mites
Causess: red mange
Symptoms: severe skin problems, loss of hair, skin rashes
In severe cases, infected dogs must be euthanized
Trombicula spp
Family Trombiculidae (chiggers)
Live in grassy areas
Larval stage is parasitic
Chew on our skin (attach to pore or hair follicle, inject salivary secretion with digestive enzymes, injest skin cells)
Saliva causes severe itching, swelling, fever
Transovarial transmission occurs
Transovarial transmission
If the mother is infected, then the offspring will be too
