Theraphosa apophysis generally resembles
Theraphosa blondi, and reaches a similar size. Immature
T. apophysis spiders have pink shading at the end of each leg, which gradually fades with each moult.
T. apophysis has an additional
stridulating organ on the coxa of the second leg and thinner femora than
T. blondi. Males of the species have tibial apophyses (projections) – hence the species name. The base colouration of both sexes is coffee brown; the legs and
opisthosoma have long scattered orange-brown hairs, with long orange hair on the femora. Mature males have a metallic sheen, described as "wine red" in colour, on the
cephalothorax, the dorsal surface of the
chelicerae, the
pedipalps, and the coxa, trochanter and femur of the legs, as well as the patella of the first leg. The female
holotype specimen had a total body length of , with the longest leg (the fourth) being long. The male specimen had a somewhat smaller body, with a total length of , and slightly longer legs, the fourth being just under long. ==Taxonomy==