What is a comblike structure on the metatarsus of the hind legs of certain spiders (Ciniflonidæ), used to curl certain fibers in the construction of their webs called?

calamistrum — A comblike structure on the metatarsus of the hind legs of certain spiders (Ciniflonidæ), used to curl certain fibers in the construction of their webs. (Webster's 1913.)

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