Data PolicyPublications | Persons | Institutes | Projects IMIS Photogallery » References Echinothurioida (aboral secondary spines) Description Points of echinothurioid spines: Aboral secondary spines with poison glands serving for defence: Left: Araeosoma thetidis: with a small venomous gland. Right: Asthenosoma varium: with a strongly inflated venomous gland.No scale provided. Author Mortensen, Theodor JPG file - 45.74 kB - 472 x 666 pixels added on 2011-02-23286 viewsFrom reference Schultz, H. (2011). Sea urchins III: Worldwide regular de... © 2011 Mortensen, Theodor Click here to return to the thumbnails overview