Marine disease ecology is a growing field of research, particularly for host organisms negatively impacted by a changing climate and anthropogenic activities. A decrease in health and increase in susceptibility to disease has been hypothesised as the mechanism behind wide-spread seagrass die-offs related to wasting disease in the past. However, seagrass wasting disease and the causative pathogen, Labyrinthula, have been vastly understudied in the southern hemisphere. Our aim was to build on the current knowledge of Australian Labyrinthula descriptions and phylogeny, while also providing a first look at wasting disease ecology in Australia. Five seagrass species along a 750 km stretch of coastline in southeastern Australia were sampled. The resulting 38 Labyrinthula isolates represented a diversity of morphotypes and five haplotypes of varying phylogenetic clade positions and virulence. The haplotypes clustered with previously-described phylogenetic clades containing isolates from Asia, USA and Europe. Pathogenicity tests confirmed, for the first time, the presence of at least two pathogenic haplotypes in Australia. While historically there have been no reports of wasting disease-related seagrass habitat loss, the presence of pathogenic Labyrinthula highlights the need for disease monitoring and research to understand seagrass wasting disease ecology in Australia.

海洋疾病生态学是一个正在发展的研究领域，特别是对于气候变化和人为活动造成负面影响的宿主生物。过去，人们认为健康下降和对疾病的易感性增加是海草大量死于与浪费疾病相关的机制。然而，在南半球，海草浪费病和致病性病原体迷宫被大大地研究了。我们的目的是在了解澳大利亚迷宫描述和系统发育的最新知识的基础上，同时也初步了解澳大利亚的浪费性疾病生态。在澳大利亚东南部沿海岸线750公里延伸的五个海草物种被采样。由此产生的38个迷宫分离株代表不同的系统进化枝位置和毒力的形态学和五个单倍型的多样性。单倍型与先前描述的包含来自亚洲，美国和欧洲的分离株的系统进化进化枝聚类。致病性测试首次确认了澳大利亚至少存在两种​​病原体单倍型。尽管历史上没有浪费与疾病有关的海草栖息地丧失的报道，但致病性迷宫的存在凸显了疾病监测和研究的必要性，以了解澳大利亚的海草浪费疾病生态。