| Name: | fin fold actinotrichium |
|---|---|
| Synonyms: | fin fold actinotrichia, median fin fold actinotrichium |
| Definition: | Portion of tissue which is a slender, horny, flexible, unsegmented fibril, which strengthens the embryonic fin fold. Actinotrichia are translucent, exhibit birefringence (double refraction) and are composed of the scleroprotein elastoidine. |
| Ontology: | Anatomy Ontology [ZFA:0000089] |