Assertion: sea urchin | /r/HasProperty | distinguishable
Facets:
value: because of two to five gonads
type: CAUSE
value: from the only other extant subclass
type: OTHER
Source sentences:
text: They are distinguishable from the only other extant subclass Irregularia because of their well-developed lantern, center placement of periostome and perioproct and two to five gonads that are sometimes fused.