| Name: | ventral fin fold |
|---|---|
| Synonyms: | anal fin fold, tail fin fold, ventral fin |
| Definition: | Region of the median fin fold that develops into the anal and caudal fin. |
| Ontology: | Anatomy Ontology [ZFA:0001069] |
| Name: | actinotrichium |
|---|---|
| Synonyms: | actinotrichia |
| Definition: | Skeletal element which is a slender, horny, flexible, unsegmented fibril which provide structural support to fin folds or fins. Actinotrichia are translucent, exhibit birefringence (double refraction) and are composed of the scleroprotein elastoidine. |
| Ontology: | Anatomy Ontology [ZFA:0005435] |