Aculeolate

Covered with or having very small needle-like structures or prickles; minutely prickly.

From Latin 'aculeolus' (very small needle), a diminutive form of 'aculeus' (needle), combined with the English adjective suffix '-ate'. The diminutive form suggests these are especially tiny, delicate needles. This botanical term evolved to describe the very fine prickly structures seen on certain plant surfaces.