Abstract Detail

Pteridology

Jones, Maia [1], Nagalingum, Nathalie [2].

Phylogenetics of grammitids (Grammitidoideae): Using molecular data and morphological characters to identify Peninsular Malaysian ferns.

The subfamily Grammitidoideae, also referred to as grammitid ferns, is found within the family Polypodiaceae. The subfamily encompasses 33 genera and approximately 750 species of ferns, which are distributed across the neotropics, southeastern Asia, and Oceania. Among genera, they display significant morphological variation in characters such as the rhizomes and rhizome scales, laminae, and arrangement of sori and sporangia. Many species of grammitid ferns are undescribed, which makes it difficult to protect the biodiversity of the ecosystems they belong to. The Malaysian Peninsula in particular is an area of focus for conservation efforts, because the biodiversity of this region is rich and includes endemic species, and grammitid ferns thrive in the mossy montane forests of this region. We sampled ferns from Penang Hill in order to contribute to the data compiled for this subfamily and gain a deeper understanding of the region’s biodiversity. We analyzed morphological characters using herbarium specimens, photographs from online herbaria, and dichotomous keys to identify the two samples. We sequenced five chloroplast loci (atpB, rbcL, rps4, trnG-trnR, and trnL-trnF) from the samples using Sanger sequencing techniques and incorporated the sequences into a dataset that consisted of the sequences of the same five chloroplast loci from 258 identified species of grammitid ferns. With this matrix, we generated a maximum likelihood tree and a Bayesian tree to identify our samples and determine the phylogenetic relationships between the identified species and our samples. Both of the samples were shown to be closely related to other species from southeastern Asia and were placed in the tropical Asian clade, which is consistent with the literature concerning grammitid ferns. We found that one of the samples, Sample 225, belongs to the genus Ctenopterella (Ctenopteris) and is the type species of the genus, Ctenopterella blechnoides. The distribution of this genus throughout our trees strongly suggests that it is not monophyletic. Based on molecular analysis the other sample, Sample 224, is related to the genera Radiogrammitis and Oreogrammitis, but examination of the morphological traits indicated that it belongs to the genus Radiogrammitis. Further evaluation of the morphology suggested that this sample belongs to a species that is new to science, or at least to Peninsular Malaysia. Future research will be conducted with the aim of identifying Sample 224 and investigating the currently unclear relationships between the species in Radiogrammitis and Oreogrammitis.

1 - Scripps College, Keck Science Department, 925 N Mills Avenue, Claremont, CA, 91711, USA
2 - California Academy of Sciences, Department of Botany, 55 Music Concourse Drive, San Francisco, CA, 94118, USA

Keywords:
grammitid ferns
systematics
biogeography.

Presentation Type: Oral Paper
Session: PTER1, Pteridology I
Location: San Pedro 1/Starr Pass
Date: Monday, July 29th, 2019
Time: 11:15 AM
Number: PTER1013
Abstract ID:416
Candidate for Awards:Edgar T. Wherry award