Most spinnerets for a spider

The spiders with the greatest number of spinnerets are those belonging to the primitive suborder Mesothelae, most of which are known only as fossils, with just a single living family known from modern times. These spiders possess(ed) four pairs of spinnerets (although in some species one pair is fused), and these are positioned under the middle of the opisthosoma (abdominal section in spiders), whereas all other spiders possess, one, two or three pairs of spinnerets, which are positioned under the rear of the opisthosoma.

The spinnerets are the silk-producing organs that the spiders utilize when creating their webs, silken ground-sheets, or silk linings for their burrows. Originally evolving from limbs, spinnerets in many spiders are highly complex structures, composed of numerous individual spigots, each of which produces a single filament, enabling the spider to combine multiple filaments in different ways to create many different types of silk for differing purposes.