Skip to main content
ARS Home » Midwest Area » Wooster, Ohio » Application Technology Research » Research » Publications at this Location » Publication #336214
Title: First report of a sexual state in an ambrosia fungus: Ambrosiella cleistominuta sp. nov. associated with the ambrosia beetle Anisandrus maiche

Author
item MAYERS, CHASE - Iowa State University
item HARRINGTON, THOMAS - Iowa State University
item Ranger, Christopher

Submitted to: Botany
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/6/2017
Publication Date: 5/8/2017
Publication URL: http://handle.nal.usda.gov/10113/5683918
Citation: Mayers, C., Harrington, T., Ranger, C.M. 2017. First report of a sexual state in an ambrosia fungus: Ambrosiella cleistominuta sp. nov. associated with the ambrosia beetle Anisandrus maiche. Botany. 95:503-512.

Interpretive Summary: Ambrosia beetles in the tribe Xyleborini possess large pouches (i.e. mycangia) that host unique fungal symbionts in the genus Ambrosiella. The fungal symbiont of a recent invasive to the USA from Asia, Anisandrus maiche, has not been identified. We consistently isolated a novel fungus, Ambrosiella cleistominuta sp. nov., from mycangia and host tree galleries of Anisandrus maiche collected in Ohio. The fungus was distinguished from other named Ambrosiella spp. by morphological characters and DNA sequences. The mycangial symbionts of ambrosia beetles has been assumed to be strictly asexual, but Ambrosiella cleistominuta produces ascospores in beetle galleries and in culture. The ascospores are relatively large, and single ascospore colonies produced ascomata and ascospores in culture, showing that Ambrosiella cleistominuta can reproduce sexually

Technical Abstract: Genera of ambrosia beetles in the tribe Xyleborini with large, mesonotal mycangia host unique fungal symbionts in the genus Ambrosiella. The symbiont of a recent invasive to the USA from Asia, Anisandrus maiche, had not been previously characterized. We consistently isolated a novel fungus, Ambrosiella cleistominuta sp. nov., from mycangia and galleries of Anisandrus maiche collected in Ohio. The fungus was distinguished from other named Ambrosiella spp. by morphological characters and DNA sequences (ITS rDNA and TEF-1a). The mycangial symbionts of ambrosia beetles had been assumed to be strictly asexual, but Ambrosiella cleistominuta produces cleistothecious ascomata with ascospores in beetle galleries and in culture. In contrast to ascomata of other Ceratocystidaceae, the relatively small ascomata of Ambrosiella cleistominuta are neckless and without ostioles. The ascospores are relatively large, and single ascospore colonies produced ascomata and ascospores in culture, showing that Ambrosiella cleistominuta is homothallic.