Line drawings and scanning electron micrographs of common types of malpighiaceous hairs A T-shaped with a short base (i.e., foot) B T-shaped with a long base C T-shaped with a very reduced base and branches with spiked cell wall D T-shaped with a very reduced base and branches with smooth cell wall E Y-shaped with a long base and two equally long branches F Y-shaped with a long base, one long and one very reduced branch G Y-shaped with a very reduced base H T-shaped with reduced base and laterally flattened (i.e., scaly) I, J detail of a velutine indumentum comprising Y-shaped hairs K, L detail of a tomentose indumentum comprising T-shaped hairs with long bases M, N detail of a sericeous indumentum comprising T-shaped hairs with very reduced bases O detail of the spikes on the cell wall of a hair branch P detail of the rugae on the cell wall of a hair branch (all line drawings and SEMs by R.F. Almeida).