Cratostigma
Cratostigma is a genus of ascidian tunicates in the family Pyuridae.
Species within the genus Cratostigma include:Cratostigma campoyi Ramos, Turon & Lafargue, 1988 Cratostigma gravellophila Cratostigma intermedia Vazquez & Ramos-Espla, 1993 Cratostigma regularis Monniot C., 1963 Cratostigma simplex Millar, 1982 Cratostigma singularis Cratostigma vestigialis Turon, 1988