The dawn of animal skeletogenesis: Ultrastructural analysis of the Ediacaran metazoan Corumbella werneri

Although the basic morphology of the Ediacaran metazoan Corumbella werneri (the type species of the genus) is well established, little is known about its skeletal tissue. Carbonaceous fragments of this fossil from the Itapucumi Group (Paraguay) reveal details of the ultrastructure of its carapace, providing an unprecedented opportunity to understand a paradigmatic issue of the evolution of skeletogenesis in early metazoans. Corumbella was a sessile predator whose carapace consisted of organic polygonal plates with pores and papillae similar to features observed in some conulariids. Its occurrence with the shelly fossil Cloudina suggests that the acquisition of protective structures in metazoans involved penecontemporaneous processes of biomineralization and secretion of organic walls.

Viceministerio de Minas y Energia de Paraguay

Viceministerio de Minas y Energia de Paraguay

Industrial Nacional del Cement (INC), Paraguay

Industrial Nacional del Cement (INC), Paraguay

CAPES (Fundacao Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior, Brazil)

CAPES (Fundacao Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior, Brazil)

Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP), Brazil

FAPESP (Fundacao de Amparo a Pesquisa do Estado de Sao Paulo, Brazil) [2004/01233-0, 2010/02677-0, 2010/19584-4]