Aspectos morfológicos de la concha y espículas de Terebratula vitrea (Brachiopoda, Testicardina)

Resum

Morphological aspects of the shell and needles of Terebratula vitrea (Brachiopoda, Testicardina)
The use of scanning electron microscopy applied to the study of the shell of Terebratula vitrea (Brachiopoda, Testicardina) has allowed to establish the presence of three different layers according to their thickness and organization. The primary layer is formed by very thin needles of calcite with variable orientation. The secondary layer, laminar in appearance, is in fact constituted by strips or prisms with a rhombic section. The third layer is formed by prismatic columns perpendicular to the surface. The whole presents a stratified structure. Each shell is perforated by numerous canaliculi of 15 micrometers of diameter.