We assessed the status of two New Zealand endemic morphodemes in the genus Sticta, currently treated as two separate taxa, Sticta filix and Sticta lacera. Both are green-algal lichens with a distinct stipe that grow in forested habitats and are suitable indicators of the indigenous vegetation health in forest ecosystems in New Zealand. They exhibit different morphologies and substrate ecologies: S. filix forms rather robust thalli, often on exposed trunks of phorophytes, with erect stems distinctly emerging from the substrate, whereas S. lacera is a more delicate lichen growing near the base of trees, usually among bryophyte mats or sheltered in the exposed portions of the phorophyte root-plate, with a prostrate, branched, stolon-like stem barely emerging from the substrate. Throughout their range, both taxa grow sympatrically and often in close proximity (syntopically). Despite the differences, ITS barcoding does not support the two morphodemes as separate species. In this study we assessed two possible explanations: (1) S. filix and S. lacera are discrete phenotypes of a single species, caused by developmental switching triggered by a discrete environmental variable, the propagules developing either on bare substrate or between bryophytes; and (2) the two morphodemes represent separate lineages, but ITS does notmore »
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- Systematic Botany
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- National Science Foundation
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The Sticta filix - Sticta lacera conundrum (lichenized Ascomycota: Peltigeraceae subfamily Lobarioideae): unresolved lineage sorting or developmental switch?
Detecting and Removing Sample Contamination in Phylogenomic Data: An Example and its Implications for Cicadidae Phylogeny (Insecta: Hemiptera)
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