DENNIS KUNKEL MICROSCOPY / SCIENCE PHOTO LIBRARY DENNIS KUNKEL MICROSCOPY / SCIENCE PHOTO LIBRARY
Coloured scanning electron micrograph (SEM) of Spiny-backed (orb weaver) spider piriform gland spigots (from the anterior spinneret) through which silk is being secreted (Gasteracantha sp.). Spiders of the Gasteracantha genus have hard, flat bodies. Three pairs of spines project from the edge of cephalothorax (abdomen). Spiny-backed spiders build vertical orb-webs that have open hubs. A male spiny-backed spider has a small abdominal gonopore from which sperm is discharged. However, actual mating organs are located on leg-like limbs called palps (or pedipalps) that are located between the jaw and first leg. In a mature male the last segment of the palp (tarsus) is a large, articulated sperm-holding reservoir and mating organ. Magnification: x1,005 when shortest axis printed at 25 millimetres.
Model release not required. Property release not required.