Cheilanthes ecuadorensis: A New Species of Cheilanthes s. s. (Pteridaceae) from Northern South America

Abstract

Abstract— Ongoing research on the taxonomically complex genus Cheilanthes (Pteridaceae; Cheilanthoideae) has resulted in the identification of a new species from Loja Province in Ecuador, Cheilanthes ecuadorensis, described and illustrated herein. Originally collected in 1988 and identified as C. cf. rufopunctata, C. ecuadorensis is clearly distinct from that species in having pubescent adaxial blade surfaces and narrow, poorly-differentiated false indusia (rather than the glabrous adaxial surfaces and wide false indusia of C. rufopunctata). Among the South American species currently included in Cheilanthes, C. ecuadorensis is superficially most similar to C. pilosa. However, our molecular phylogenetic analyses indicate that C. ecuadorensis is sister to C. micropteris, the morphologically disparate generitype of Cheilanthes. Here we examine the phylogenetic relationships, morphology, cytogenetics, and geography of these four South American Cheilanthes species in a study that, once again, highlights the importance of herbaria in the process of new species discovery.

Taxonomic updates of <i>Cheilanthes</i> Sw. (Pteridaceae) in Peru, with a conservation assessment for four endemics

“…Tryon (1964) and Tryon and Stolze (1989) considered it a synonym of Cheilanthes pilosa Goldm., observing narrower ultimate segment and thicker texture, explained as a probable response to drier environmental conditions. Ponce and Scataglini (2022) and Sosa et al (2021) accepted C. andina as a distinct species from C. pilosa, based on few morphological characters. Cheilanthes andina is characterized by its small frond size, adaxially sulcate petiole with dispersed scales, and with scarce indument in the adaxial surface of the lamina (Ponce, pers.…”

“…Cheilanthes andina was reported to have 64 spores per sporangium (Sosa et al 2021). It was proposed as belonging to the Australasian-South American clade based on morphological features (Ponce & Scataglini 2022), and therefore, its affinities are not close to C. pilosa (in the South American clade) as its morphology implies.…”

“…Cheilanthes andina, originally described from Peru, is only known from the department of Lima, and it is also reported from Bolivia (Sosa et al 2021), and from Chile (Ponce & Scataglini 2022) based on synonymizing C. valdiviana Phil., whose type was collected in Valdivia, southern Chile. Therefore, suggesting a wider distribution in Peru, as described here.…”

“…Cheilanthes is a complex genus, whose circumscription is still uncertain. Both, Ponce and Scataglini (2022), and Sosa et al (2021) had underlined that the delimitation of the genus Cheilanthes is still in progress, while its affinities within the cheilanthoid ferns are supported as a member of the hemionitid clade (Windham et al 2009). Progress in molecular studies have also shown that the delimitation in the treatment of Peru is untenable, in part given by the segregation of several species to Aleuritopteris, Astrolepis, Doryopteris, Gaga, and Myriopteris.…”

“…The genus Cheilanthes has benefited from several cytological, morphological and molecular phylogenetic studies, like those of Benham and Windham (1992), Gastony (1995), Li et al (2012), Grusz et al (2013), Scataglini (2018, 2022) and Sosa et al (2021) allowing for a better definition of its limits and therefore the emerging of a new genus concept. Several genera have been segregated from Cheilanthes, which have also implications for composition and richness of the Peruvian fern flora.…”