part of ocellar triangle FBbt:00004495 The ocellar triangle does not correspond to a separate sclerite (Ferris, 1950). Region of the integument of the medial part of the vertex of the adult head, where the ocelli are located (Ferris, 1950). It has a smooth surface, in contrast to the surrounding cuticle (Ferris, 1950). IOC fly_anatomy.ontology vertical triangle interocellar cuticle https://www.ento.csiro.au/biology/drosophila/melanogaster.html?ocellar%20triangle region of integument vertex