Antennatula katumotoi, a new euantennariaceous sooty mould, with a Hormisciomyces-like synasexual morph from central Honshu, Japan

<i>Euantennaria pleioblasti</i> sp. nov. (<i>Euantennariaceae</i>) and <i>Metacapnodium</i> cf. <i>quinqueseptatum</i> (<i>Metacapnodiaceae</i>), two mixed sooty moulds in subicula on <i>Pleioblastus</i> sp. in Taiwan

Black subicula, comprising a mixture of two sooty moulds of Euantennariaceae and Metacapnodiaceae, on Pleioblastus were collected in Batongguan, alt. ca. 2800 m, Nantou County, Taiwan in 1984. The former sooty mould is described and illustrated as Euantennaria pleioblasti sp. nov., an asexually typified species of the genus, as currently circumscribed with the application of the single name nomenclature for pleomorphic fungi. It is characterized by cylindrical, finely to coarsely roughened hyphae and black synnemata bearing massive fusiform, straight, mostly 11-14-septate phragmoconidia in a subglobose to obovoid head; its reliable sexual morph is obscure. The latter was identified as Metacapnodium cf. quinqueseptatum. It features the capnobotrys- and capnophialophora-like asexual morphs, in addition to the sexual morph with 5-7-septate ascospores. These sooty mould taxa are newly added to the mycobiota of Taiwan.

Sooty molds from the Jurassic of Patagonia, Argentina

PREMISE

The sooty molds are a globally distributed ecological group of ascomycetes with epiphyllous, saprotrophic habit, comprising several phylogenetically distant taxa (i.e., members of the classes Dothideomycetes and Eurotiomycetes). Their fossil record extends almost continuously back to the early Cretaceous; however, they are hypothesized to have originated in the early Mesozoic. Here, we describe new specimens of sooty molds associated with conifer leaves from Jurassic hot spring deposits of Patagonia, Argentina.

METHODS

Thin sections of chert samples from the La Matilde Formation, Deseado Massif (Santa Cruz, Argentina) were observed using light microscopy.

RESULTS

The fungi occur on the surface and axils of leafy twigs with podocarpaceous affinities, forming dense subicula comprised by opaque moniliform hyphae. Additionally, several asexual and sexual reproductive structures are observed. On the basis of vegetative (i.e., dense subicula composed of moniliform hyphae; hyphae composed of opaque cells deeply constricted at the septa) and reproductive characters (i.e., poroconidial and sympodioconidial asexual stages and diverse spores), two morphotypes were identified with affinities within lineages of the subphylum Pezizomycotina that encompass the ecological group of sooty molds, and a third morphotype was within the phylum Ascomycota.

CONCLUSIONS

This finding extends the fossil record of sooty molds to the Jurassic and their geographic fossil range to the South American continent. In particular, their association with podocarpaceous conifers is shown to be ancient, dating back to the Jurassic. This new record provides an additional reference point on the diversity of interactions that characterized Jurassic forests in Patagonia.