Further evidence for the hybrid status of the Brazilian native fern Hypolepis ×paulistana (Dennstaedtiaceae)

AGUSTINA YAÑEZ; SCHWARTSBURD P. B. ; MARQUEZ G. J.

ANAIS DA ACADEMIA BRASILEIRA DE CIENCIAS.

ACAD BRASILEIRA DE CIENCIAS

Lugar: Rio de Janeiro; Año: 2022 vol. 94

0001-3765

ABSTRACT Hypolepis ×paulistana was described in 2016 as a putative hybrid involving H. stolonifera and H. rugosula, known from a single collection. The assumption of the hybrid status was based solely on the intermediate morphology of the sporophyte, compared to its parents. Also based on morphological similarities, another candidate would be H. rigescens (Kunze)T. Moore. In the present work, we tested the hybrid status of that fern adding palynological studies and studying in more detail the chloroplast sequences to test the maternal progenitorof the species. Hypolepis ×paulistana has both well formed spores, as well as spores with some kind of anomaly in their morphology or development. The size of the regular spores and the abnormalities are evidence that H. ×paulistana is a diploid, probably infertile hybrid. The ornamentation of the regular spores of H. ×paulistana is similar to that of H. stolonifera. The chloroplast sequences of H. ×paulistana are identical to those of H. stolonifera, as well as their sister position within the global, phylogenetic tree of the genus. Thus, we provide new evidence for the hybrid status of H. ×paulistana, and we suggest thatH. stolonifera is the maternal paren