Ascidian Home Page for United States
Spawning of Phallusia nigra
Coral Reef ascidians ecology (Botryllus eilatensis movie)
Tropical ascidians of the Red Sea
http://depts.washington.edu/ascidian/ 
Ascidiacea World Database
http://www.marinespecies.org/ascidiacea/index.php
Dutch Ascidians Homepage
http://ascidians.com/
Tunicata List Discussion Forum
https://www.jiscmail.ac.uk/cgi-bin/webadmin?A0=tunicata