This is a term introduced by Kury (2014) to describe the structure of apophyses of coxa and trochanter IV of the males of many species of Cryptogeobiidae.
It was originally abbreviated as FAp.
According to original definition, they are "apophyses of basal segments of male leg IV, which are not hardened conical processes, but made of many lesser sclerotized units that give an impression of a bundle of transparent fibres."
↑ 1.01.1Kury, A.B. (2014) Why does the Tricommatinae position bounce so much within Laniatores? A cladistic analysis, with description of a new family of Gonyleptoidea (Opiliones, Laniatores). Zoological Journal of the Linnean Society, 172, 1–48.