Li You, Bateman Craig Christopher, Skelton James, Jusino Michelle Alice, Nolen Zachary John, Simmons David Rabern, Hulcr Jiri
School of Forest Resources and Conservation, University of Florida, Gainesville, FL, USA.
Department of Entomology and Nematology, University of Florida, Gainesville, FL, USA.
Fungal Biol. 2017 Nov;121(11):984-989. doi: 10.1016/j.funbio.2017.08.004. Epub 2017 Aug 26.
The ambrosia fungus Flavodon ambrosius is the primary nutritional mutualist of ambrosia beetles Ambrosiodmus and Ambrosiophilus in North America. F. ambrosius is the only known ambrosial basidiomycete, unique in its efficient lignocellulose degradation. F. ambrosius is associated with both native American beetle species and species introduced from Asia. It remains unknown whether F. ambrosius is strictly a North American fungus, or whether it is also associated with these ambrosia beetle genera on other continents. We isolated fungi from the mycangia and galleries of ambrosia beetles Ambrosiodmus rubricollis, Ambrosiodmus minor, Ambrosiophilus atratus, and Ambrosiophilus subnepotulus in China, South Korea, and Vietnam. Phylogenetic analyses suggest that all Asian and North American isolates represent a single haplotype. These results confirm Flavodon ambrosius as the exclusive mutualistic fungus of multiple Ambrosiodmus and Ambrosiophilus beetle species around the world, making it the most widespread known ambrosia fungus species, both geographically and in terms of the number of beetle species. The Flavodon-beetle symbiosis appears to employ an unusually strict mechanism for maintaining fidelity, compared to the symbioses of the related Xyleborini beetles, which mostly vector more dynamic fungal communities.
美味齿菌（Flavodon ambrosius）是北美食菌小蠹（Ambrosiodmus）和食菌长小蠹（Ambrosiophilus）的主要营养共生菌。美味齿菌是已知唯一的食菌担子菌，在高效降解木质纤维素方面独具特色。美味齿菌与美洲本土甲虫物种以及从亚洲引入的物种均有关联。目前尚不清楚美味齿菌是否严格来说是一种北美真菌，或者它在其他大陆是否也与这些食菌小蠹属有关联。我们从中国、韩国和越南的红颈食菌小蠹（Ambrosiodmus rubricollis）、微小食菌小蠹（Ambrosiodmus minor）、黑腹食菌长小蠹（Ambrosiophilus atratus）和近小食菌长小蠹（Ambrosiophilus subnepotulus）的菌囊和虫道中分离出了真菌。系统发育分析表明，所有亚洲和北美的分离株代表单一单倍型。这些结果证实美味齿菌是全球多种食菌小蠹和食菌长小蠹甲虫物种唯一的共生真菌，使其成为在地理分布和甲虫物种数量方面已知分布最广泛的食菌真菌物种。与相关长小蠹科甲虫的共生关系相比，美味齿菌与甲虫的共生关系似乎采用了一种异常严格的机制来维持专一性，长小蠹科甲虫大多携带更具动态变化的真菌群落。
