Abstract Detail



Systematics

Jauregui Lazo, Javier [1], Brinda, John [2], Mishler, Brent [3].

Phylogenetic systematics of Syntrichia Brid. in South America.

Syntrichia Brid. represents one of the most complex genera of Pottiaceae, a family of mosses characteristic of harsh environments. It contains approximately 100 named species worldwide characterized by an unusual amount of ecological and morphological variation among close relatives. It is a dominant group of mosses in habitats ranging from temperate/polar and alpine meadows to late-successional desert biocrusts across western North America and Europe. Yet 40% of species occur in the Neotropics, in which most of the species are concentrated in xerophytic environments of dry punas and valleys in the Andes, or polar climates from the southernmost regions of South America. Despite its greatest ecological diversity and cosmopolitan distribution, the genus appears to be monophyletic. A set of morphological characters has been used to discover synapomorphies that separate it from its closest relatives- Tortula, Hennediella, Chenia, and Willia- such as an abrupt transition between basal and upper laminal cells, red laminal KOH color reaction, and absence of differentiated dorsal epidermis in the costa. However, the placement of species within the genus is still difficult and needs careful morphological analysis and the addition of molecular data, which we are gathering from samples of all named species world-wide, using a nextgen genome skimming approach. As part of a broader collaborative project we are reexamining the phylogenetic systematics of the group worldwide, but this talk will focus on understanding the taxa from South America. Due to its taxonomic complexity, the group has been subjected to regional taxonomic treatments, which are concentrated mostly in the Northern Hemisphere. No systematic studies have been done for southern South America, including the Andes of Ecuador, Peru, and Chile, or the Mediterranean and Patagonian steppe of Chile, where Syntrichia shows a remarkable diversity in terms of taxonomic richness and morphology.  We use newly developed morphological characters to distinguish major clades and species - overall leaf shape, stance, border, hairpoint presence and length, the distribution of cell types within a leaf, papillae and mammillae on leaf cells, and costa anatomy- for integration with molecular data in total-evidence phylogenetic analyses. 


1 - University of California Berkeley, Integrative Biology, 4156 Vallley Life Sciences Building, Berkeley, CA, 94720, USA
2 - Missouri Botanical Garden, 4344 Shaw Blvd., St. Louis, MO, 63110, USA
3 - University Of California, Berkeley, Department Of Integrative Biology, University And Jepson Herbaria, 1001 Valley Life Sciences Building, # 2465, Berkeley, CA, 94720, United States

Keywords:
Syntrichia
systematics
South America.

Presentation Type: Oral Paper
Number:
Abstract ID:640
Candidate for Awards:George R. Cooley Award


Copyright © 2000-2019, Botanical Society of America. All rights reserved