Spider spinneret (Unknown sp.)

SEM of a spider spinneret, the organs responsible for spinning silk. These silk-weaving appendages vary widely between arachnid species. For true spiders they consist of the colulus (a vestigial spinneret), anterior spinneret, median spinneret and posterior spinneret, all of which are shown here. Conversely the spinnerets of mygalomorphs have a simple structure with 1–3 undifferentiated lobes that lack the ability to produce the expansive array of specialised spindroins found in other spiders. False-coloured scanning electron micrograph; x 80; this image is approximately 900 micrometers wide.