Module 11 Spiders Flashcards Preview

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Flashcards in Module 11 Spiders Deck (22):
1

taxonomy of spiders

Kingdom Animalia
Phylum Athropoda
Subphylum Chelicerate
Class Merostomata
Class Arachnida

2

subphylum Chelicerata key characteristics

chelicera: 1st paired appendage before mouthparts
lack antennae
tagmata: cephlathorax (head/thorax fusion) and abdomen
4 pairs of legs

3

class Merostomata species and characteristics

horseshoe crab: Limulus polyphemus
copper-based blood
limulus amebocyte lysate (LAL) is extracted from blood and used to test for presence of bacteria in blood
red knot birds feed on their eggs

4

class Arachnida species and characteristics

spiders, ticks, mites, scorpions
prosoma (cephlathorax): pair of chelicerae, pair of pedipalps, 4 pairs of walking legs
opisthosoma (abdomen)

5

order scorpiones

ancient group
tropical/subtropical or arid environments
carry young on back
most not aggressive
nocturnal

6

scorpion anatomy

venemous sting (25 sp)
large pedipalps with telson to crush prey and inject venom

7

medical importance of scorpions

localized swelling or pain, blood-filled blisters, and sloughing of skin
18 spp in texas
systemic: pain, numbness, difficulty swallowing, muscle spasms
allergic reactions

8

prevention and control of scorpions

remove debris
slightly raise homes
borax and diatomaceous earth
protective clothing

9

order Uropygi

whip scorpions/Vinegaroons
whip-like tails
not poisonous but can spray vinegar-like acid

10

order Solifugae

solpugids, sun-spiders, etc
typically nocturnal
urban legends for large size but actually only 5 in
rapid movement
powerful chelicerae
can bite but not poisonous

11

order Araneae

spiders
all produce silk for webs
8 eyes

12

mating for spiders

sperm stored in palp in male then transferred to spermatheca duct in females
males perform special dances to attract females but then die shortly after

13

development of spiders

occurs within silken egg sac
egg - spiderlings - adult
live only about 1 year

14

spider envenomation

araneism: being bit by spider
venom injected by chelicerae but varies greatly among taxa

15

tarantulas

most not very toxic
Texas Brown Tarantula (pet)
urticating hairs: barbed hairs on abdomen can penetrate human skin and cause mild reactions

16

Austrialian Funnel-web spider

considered one of most deadly spiders in world
Genera Atrax and Hadronyche
atracotoxins
envenomation: reaction to the toxin and pain from the bite; fangs are hardened and large (can go through a toenail)

17

loxosceles

aka Fiddle-back, Brown recluses, or violin spiders
behavior: nocturnal, rely on venom not webs

18

loxoscelism

disease from being bit by a brown recluse
tissue damage (sphingomyelinase D destroys cells)
systemic: fever, nausea/vomiting, joint pains, hemolysis intravascular coagulation, renal failure

19

black widow

Latrodectus mactans
sexual dimorphism
shy, close to ground, messy webs
reproduces 200 eggs per sac (10 in lifetime)

20

brown widow

Latrodectus geometricus
sexual dimorphism
dorsal: 3 pairs of irregular spots
ventral: hourglass (dull orange)
less severe symptoms than Black widow

21

latrodectism

syndrome caused by bite of any Latrodectus sp
pain, nausea/vomiting, faintness, cramps, profuse sweating, spasms of jaw muscle
fatality in 5% of cases

22

prevention and control of spiders

don't handle spiders!
remove spider webs
pesticides
protective clothing
be cautious of standing material