Sun Dan, Ellepola Gajaba, Herath Jayampathi, Meegaskumbura Madhava
Guangxi Key Laboratory for Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning 530000, China.
Department of Zoology, Faculty of Science, University of Peradeniya, Peradeniya, Kandy 20400, Sri Lanka.
J Fungi (Basel). 2023 Sep 8;9(9):911. doi: 10.3390/jof9090911.
The chytrid fungal pathogens () and () are driving amphibian extinctions and population declines worldwide. As their origins are believed to be in East/Southeast Asia, this region is crucial for understanding their ecology. However, screening is relatively limited in this region, particularly in hotspots where lineage diversity is high. To address this gap, we conducted an extensive screening involving 1101 individuals from 36 amphibian species, spanning 17 natural locations and four captive facilities in the biodiversity-rich Guangxi Zhuang Autonomous Region (GAR). Our PCR assays yielded unexpected results, revealing the complete absence of in all tested samples including 51 individuals with presence. To understand the potential distribution of , we created niche models, utilizing existing occurrence records from both Asia and Europe. These models estimated potential suitable habitats for largely in the northern and southwestern parts of the GAR. Although was absent in our samples, the niche models identified 10 study sites as being potentially suitable for this pathogen. Interestingly, out of these 10 sites, was detected at 8. This suggests that and could possibly co-exist in these habitats, if were present. Several factors seem to influence the distribution of in Asia, including variations in temperature, local caudate species diversity, elevation, and human population density. However, it is climate-related factors that hold the greatest significance, accounting for a notable 60% contribution. The models propose that the specific climatic conditions of arid regions, primarily seen in the GAR, play a major role in the distribution of . Considering the increased pathogenicity of at stable and cooler temperatures (10-15 °C), species-dependent variations, and the potential for seasonal - interactions, we emphasize the importance of periodic monitoring for within its projected range in the GAR. Our study provides deeper insights into 's ecological niche and the knowledge generated will facilitate conservation efforts in amphibian populations devastated by chytrid pathogens across other regions of the world.
壶菌真菌病原体（Batrachochytrium dendrobatidis， Bd）和Batrachochytrium salamandrivorans（ Bsal）正在导致全球两栖动物灭绝和种群数量下降。由于它们被认为起源于东亚/东南亚，该地区对于了解它们的生态学至关重要。然而，该地区的筛查相对有限，特别是在Bsal谱系多样性高的热点地区。为了填补这一空白，我们在生物多样性丰富的广西壮族自治区（GAR）进行了广泛的筛查，涉及来自36种两栖动物的1101个个体，涵盖17个自然地点和4个圈养设施。我们的PCR检测产生了意想不到的结果，发现在所有测试样本中完全没有Bsal，包括51个有Bd存在的个体。为了了解Bsal的潜在分布，我们利用来自亚洲和欧洲的现有出现记录创建了生态位模型。这些模型估计Bsal的潜在适宜栖息地主要在GAR的北部和西南部。虽然我们的样本中没有Bsal，但生态位模型确定了10个研究地点可能适合这种病原体。有趣的是，在这10个地点中，有8个检测到了Bd。这表明如果Bsal存在，它和Bd可能在这些栖息地共存。几个因素似乎影响Bsal在亚洲的分布，包括温度变化、当地有尾类物种多样性、海拔和人口密度。然而，与气候相关的因素最为重要，占显著的60%。模型表明，主要在GAR出现的干旱地区的特定气候条件在Bsal的分布中起主要作用。考虑到Bd在稳定和较凉爽温度（10-15°C）下致病性增加、物种依赖性变化以及季节性Bd - Bsal相互作用的可能性，我们强调在GAR其预测范围内对Bsal进行定期监测的重要性。我们的研究为Bsal的生态位提供了更深入的见解，所产生的知识将有助于保护世界其他地区受壶菌病原体破坏的两栖动物种群。
