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Rocky Mountain Wood Tick

Dermacentor andersoni


Diagnostic features: Larva only has 3 pairs of legs. Nymph has 4 pairs. Single pair of spiracular openings (stigmata) close to the coxae (leg bases or segments) of the 4th pair of legs (except in larvae) Terminal capitulum (mouthparts) visible from above in all stages except the egg, of course. A large sclerite called the Scutum present dorsally behind the capitulum. The scutum almost entirely covers the back of the male, but only partly covers the back of the female. Eyes, if present, are on the scutum. Sexual dimorphism in size and colour is frequent. The female is often larger. Posterior margin of opisthosoma usually sub-divided into sclerites callel festoons. Pedipalps rigid along the chelicerae, not leg-like. Single pair of spiracular openings (stigmata)

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JeffStreifling 9 years ago


notsoclosetnerd1 9 years ago

So menacing! Haha....nice shot!

Spotted by

Idaho, USA

Spotted on Apr 23, 2012
Submitted on Oct 4, 2012

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