The identity of the epiphytic fern Pyrrosia stigmosa (Sw.) Ching succeeded in its confirmation through integrative morphological and molecular analyses in West Sumatra, Indonesia. This finding expands the known geographic distribution of the species and contributes novel data to the global systematics of the genus Pyrrosia. Specimens collected from Silokek Geopark and Mount Padang, Indonesia, underwent identification based on key diagnostic traits, including narrowly grooved costae, dentate rhizome scales, and scattered sori. Species identity verification used the chloroplast trnL-F intergenic spacer marker (IGS) sequencing, showing 99.55% similarity to P. stigmosa (GenBank accession JX103800.1). For phylogenetic reconstruction, a dataset of 50 accessions representing various Pyrrosia species as retrieved from the GenBank database attained alignment with the newly generated sequence. Maximum likelihood analysis placed the West Sumatran samples within a strongly supported clade together with P. costata, indicating a close sister-species relationship. The combined morphological and molecular evidence provides a robust basis for delimiting P. stigmosa from morphologically similar taxa. Ecologically, the discovery highlights the adaptability of P. stigmosa to both lithophytic and epiphytic habitats in limestone-rich forest systems. This study represents the first documented record of Pyrrosia stigmosa in West Sumatra, extending its known distribution range and offering valuable insights into the biogeography and systematics of Pyrrosia in Southeast Asia.
Pyrrosia stigmosa, Pyrrosia, morphological and molecular studies, taxonomy, trnL-F IGS, similarity, adaptability
The investigation on Pyrrosia stigmosa (Sw.) Ching obtained a successful recording in West Sumatra, Indonesia.