Fungal fossils are rare and so every find deserves a celebration. Only one fossil of Laboulbeniales is known in the literature, †Stigmatomyces succini on a fly embedded in Bitterfeld amber. Since 2012, Danny started working on another piece of Dominican amber, which contained a beetle with a thallus of Laboulbeniales. Both the beetle host and its parasite represented undescribed species and were described as †Proptomaphaginus alleni (Coleoptera, Leiodidae) and †Columnomyces electri (Laboulbeniales, Laboulbeniaceae). The fungus could only be accurately described by using a phase contrast synchrotron X ray microtomography approach, resulting in 3D reconstructions and even cellular dissections of organisms.
After screening specimens of extant species of Proptomaphaginus in museum and personal collections, two more new species of Columnomyces were found and formally described in the same paper, Columnomyces hispaniolensis and C. peckii. All in all, this study points at a unique parasitic association between Proptomaphaginus and Columnomyces since at least 15 million years.
Citation: Perreau M, Haelewaters D, Tafforeau P. 2021. A parasitic coevolution since the Miocene revealed by propagation phase-contrast synchrotron X-ray microtomography and the study of natural history collections. Scientific Reports 11: 2672. https://doi.org/10.1038/s41598-020-79481-x
Link to the paper (open access): https://www.nature.com/articles/s41598-020-79481-x.
Link to a blog post on Danny's website: http://www.dannyhaelewaters.com/a-new-species-of-laboulbeniales/.