Figure 3
From: A putatively extinct higher taxon of Spirotrichea (Ciliophora) from the Lower Cretaceous of Brazil
Light microscopy photograph (a) and volumetric reconstructions (b–j) of Palaeohypothrix bahiensis gen. et sp. nov. holotype. (a) Ventral side to show the transverse cirri-like structures (also in i,j) outlined. Arrowhead points to one of said structures. (b) Anterior region of body showing crown membranelles (arrowheads) and one intermembranellar ridge (asterisk). (c) Detail of right quadrant of peristome. Figure inset shows some insertion pores of ciliary structures forming the frontal brush immediately ahead of paroral. (d–f) Different focal planes of the anterior region to show frontal ciliature. Arrowheads indicate pits from where putative ciliary structures emerged. (g) Right lateral view. (h) Focal plane of the anterior region to show remnants of the frontal and fronto-ventral ciliature elements. Arrowhead shows insertion places of ciliary structures. (i,j) Insertion pits (i) and remnants of transverse cirri-like structures. Legends: AZM adoral zone of membranelles, CV contractile vacuole, F frontal ciliary structures, FV fronto-ventral ciliary structures, P paroral membrane, TC(?) possible transverse cirri-like structures. Scale bar = 20 µm.
