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ABSTRACT Studying declining and rare species is inherently challenging, particularly when the cause of rarity is emerging infectious diseases (EIDs). Tracking changes in the distribution of pathogens that cause EIDs, and the species made scarce by them, is necessary for conservation efforts, but it is often a time and resource intensive task. Here, we demonstrate how using environmental DNA (eDNA) to detect rare species—and the pathogens that threaten them—can be a powerful tool to understand disease dynamics and develop effective conservation strategies. Amphibian populations around the world have undergone rapid declines and extinctions due to the emerging fungal pathogen,Batrachochytrium dendrobatidis(Bd). We developed and validated a qPCR assay using eDNA sampling methods for some of the most imperiled amphibian species, harlequin frogs (Atelopus varius,Atelopus zeteki,andAtelopus chiriquiensis), and applied this assay in concert with a standard qPCR assay forBdin rainforest streams of Panamá. We confirmed the presence ofAtelopusat sampling locations across three regions. In addition, we used genomic analysis of eDNA samples to show thatBdin Panamá falls within the Global Panzootic Lineage, a lineage associated with disease‐induced declines. We detectedBdDNA in most of our historic sites, and its concentration in water samples correlated with stream characteristics and the pathogen load of the local amphibian community. These results suggest that some populations ofAtelopuspersist in their historic localities. They also show how eDNA analysis can be effectively used for monitoring species presence, pathogen concentrations, and the distribution and spread of pathogen lineages. EIDs are a growing threat to endangered species around the world. Simultaneous detection of rare and declining host species and their pathogens with eDNA will help to provide key insights for effective conservation management.
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The status of the anomalepidid snake Liotyphlops albirostris and the revalidation of three taxa based on morphology and ecological niche models
Abstract Liotyphlopsis a genus of blindsnakes distributed in Central and South America. We reviewed specimens ofLiotyphlops albirostrisalong its current distribution range and, based on morphological data and ecological niche modeling analyses, we restrict the geographical range ofL. albirostrisand validate three previously described species. In this revision, we describe the morphological variation in the populations from Panamá, Colombia, Ecuador, and Venezuela, and propose a new taxonomic arrangement. We revalidate three previous synonyms ofL. albirostristo full species status, while dividing the populations from Colombia in two subspecies―one attributed to a previously recognized species from the Caribbean region, and a new one from the Andean region. The new species differs fromL. albirostrisfrom Panamá in cephalic scale arrangements that effectively reduces the previously reported variability of these scales inL. albirostris. We also explore some osteological differences that are congruent with the variation observed. We hope that the recognition of these new species better represents the diversity withinLiotyphlops, helping to bring these new species out of their cryptic status so that they will be considered in future conservation efforts.
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- Award ID(s):
- 1902242
- PAR ID:
- 10555491
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- The Anatomical Record
- Volume:
- 304
- Issue:
- 10
- ISSN:
- 1932-8486
- Page Range / eLocation ID:
- 2264 to 2278
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1002/ar.24730
