Estructura de los filtros branquiales de ascidias (Tunicados)

Resum

Structure of the branchial filters of ascidians (Tunicates)
The morphology of the food trapping mucous films of nine ascidian species has been analvzed by means of SEM and TEM studies, and some characteristics of these filteis have been evaluafed by image analysis. The results show that the filters consist of a delicate mesh of rectangular pores whose sizes range (in the preserved material) between 0.12 x 0.08 and 1.16 x 0.36 µm, which represent most probably an underestimation of their actual in vivo sizes. A tendency towards more rectangular nets accompanies branchial complication, but the minimal dimensions of the nets are kept at similar values (retaining filtration efficiency with less mucus production).