Evolution of anatomical characters in Acianthera section Pleurobotryae (Orchidaceae: Pleurothallidinae)
Fig 4
Acianthera and Pleurothallopsis nemorosa, floral micromorphology: dorsal sepals (A-D), lateral sepals (E-G) papillae and trichomes (H-K), petals (L-O). (A) Acianthera gracilisepala, sepal apex with stomata (arrow). (B) Acianthera crepiniana, ciliate entire margin. (C) Acianthera saundersiana, papillose entire margin. (D) Acianthera atropurpurea, papillose delimited margin. (E) Acianthera fenestrata. (F) Pleurothallopsis nemorosa. (G) Acianthera saundersiana. (H) Acianthera octophrys, stomata (st), simple trichomes (tr), conical papillae (cp) and simple papillae (sp). (I) Acianthera atropurpurea, aciculate apex papillae. (J) Acianthera fenestrata, obovate (ob) and obpyriform papillae (op). (K) Pleurothallopsis nemorosa, simple (sp) and obpyriform papillae (op). (L) Acianthera mantiquyrana. (M) Pleurothallopsis nemorosa. (N) Acianthera saurocephala. (O) Acianthera hatschbachii, simple papillae (sp) on petals.