 The size range for females worms is 65 to 81 mm long and 0.21 to 0.25 mm in diameter but unknown for males.Adult worms recovered from experimentally infected Patas monkeys measured 24 to 28 mm long and 70 to 80 μm in diameter (males) and 32 to 62 mm long and .130 to .160 mm in diameter (females).Adults produce unsheathed and non-periodic (sub-periodic in "M. perstans") microfilariae that reach the blood stream.