Module 12 Mites

Question 1

mites taxonomy

Answer 1

Subphylum chelicerate
Class Arachnida
Order Acari

Question 2

order acari characteristics

Answer 2

largest chelicerate group

various habitats: terrestrial, aquatic, parasitic

Question 3

anatomy of mites

Answer 3

magma: gnathosoma (mouthparts), pedipalps, chelicerate
idiosoma: fusion of thorax/abdomen

Question 4

development of mites

Answer 4

egg - larva - nymph - adult
nymph/adult have 4 pairs of legs
larvae only 3 pairs

Question 5

medical importance of mites

Answer 5

1. temporary irritation of skin due to bite
2. persistent dermatitis by skin invasion
3. mite-induces allergies
4. transmission of pathogens
5. intermediate host for tapeworms
6. invasion of canals and passages
7. acrophobia (feat of mites)
8. delusory acariosis: psychological condition of attack by mites

Question 6

disease conditions with mites

Answer 6

Acarinism: infestation with mites
Ascariasis: any disease caused by mites

Question 7

mite-induced Dermatitis

Answer 7

Demodicidae and Sarcoptidae are important families

is a skin reaction from feeding or burrowing of mites

Question 8

Family Trombiculidae

Answer 8

Chiggers
-larval stage of red velvet mites
-yellow, orange, or red
-found in large numbers
50 spp affect humans (Trombicula alfreddugesi*)

Question 9

development of chiggers

Answer 9

eggs on ground - larva
larvae picked up by host on whom they feed
continue development as free-living predators

Question 10

Trombiculosis

Answer 10

infestation by chiggers

• ectoparasites: don’t burrow into skin, just pierce skin with chelicerae and then skin swells around it
• don’t feed on blood but on skin cells
• stylostome is used as a feeding tube
• symptoms: bite site irritation, itching
• treatment: application of medicine within first few hours to alleviate itching/infection