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Leal-Dutra, C. A.

Publications and source records attributed to Leal-Dutra, C. A..

5 recordsLinked to original sources

Revisions to the Gliophorus irrigatus complex (Agaricales, Hygrophoraceae, Gliophorus, section Unguinosae) including a new waxcap, G. alboviscidus, from the UK but detected globally via soil eDNA, two new species from eastern North America, G. fumosus and G. parafumosus, plus a new species, G. calunus, and a new combination of Hygrophorus subaromaticus in Gliophorus from western North America.

Here we report the discovery of four new agaricoid fungi in the Gliophorus irrigatus complex of the family Hygrophoraceae. Gliophorus alboviscidus sp. nov. from the UK is morphologically identical to the European G. irrigatus (which we neotypify), except that its basidiome is white or pale Buff coloured vs brownish grey. Two new species from eastern North America, Gliophorus fumosus sp. nov. (provisional name Gliophorus sp. irrigatus-IN01), and Gliophorus parafumosus sp. nov (previously labelled G. irrigatus) resemble G. irrigatus s.s. in colour and morphology but their distributions are restricted to North America. Phylogenetic reconstruction revealed that these samples form distinct clades, with >10% ITS sequence divergence from European G. irrigatus s.s. and from each other. Though G. alboviscidus sp. nov. is currently known only from two locations in the UK, searches for related sequences from eDNA (environmental DNA) sequence repositories (UNITE/GlobalFungi) suggested that this species is more widely distributed in Eurasia. G. fumosus and G. parafumosus sequences from eastern North America were divergent from both European G. irrigatus and G. alboviscidus; both were more closely related to another species with a strong odour and white/Buff basidiomes from northwestern North America, Hygrophorus subaromaticus for which we sequenced the holotype and recombine in the genus Gliophorus. We also describe a new species from northwestern North America, G. calunus sp. nov. (provisional name Gliophorus sp. irrigatus-CA01), based on vouchered specimens photographed and sequenced by an paraprofessional group, CA FUNDIS. We highlight the importance of citizen scientist groups and paraprofessionals in documenting macrofungal species and their distributions via databases such as iNaturalist, Mushroom Observer and MycoMap. Further, we discuss reasons eDNA distributions are often larger than known distributions of basidiomes, including G. alboviscidus and G. fumosus.

evolutionary biology↗

Genomic Signatures of Domestication in a Fungus Obligately Farmed by Leafcutter Ants

The naturally selected fungal crop (Leucoagaricus gongylophorus) farmed by leafcutter ants shows striking parallels with artificially selected plant crops domesticated by humans (e.g., polyploidy, engorged nutritional rewards, dependence on cultivation). To date, poorly resolved L. gongylophorus genomes based on short-read sequencing have constrained hypotheses about how millions of years under cultivation by ants shaped the fungal crop genome and potentially drove domestication. We use PacBio HiFi sequencing of L. gongylophorus from the leafcutter ant Atta colombica to identify 18 putatively novel biosynthetic gene clusters that likely cemented life as a cultivar (e.g., plant fragment degradation, ant-farmer communication, antimicrobial defense). Comparative analyses with cultivated and free-living fungi showed genomic signatures of stepwise domestication transitions: 1) free-living to ant-cultivated: loss of genes conferring stress response and detoxification, 2) hyphal food to engorged nutritional rewards: expansions of genes governing cellular homeostasis, carbohydrate metabolism, and siderophore biosynthesis, and 3) detrital provisioning to freshly cut plant fragments: gene expansions promoting cell wall biosynthesis, fatty acid metabolism, and DNA repair. Comparisons across L. gongylophorus fungi farmed by three leafcutter ant species highlight genomic signatures of exclusively vertical clonal propagation and widespread transposable element activity. These results show how natural selection can shape domesticated cultivar genomes towards long-term ecological resilience of farming systems that have thrived across millennia.

evolutionary biology↗

A domesticated fungal cultivar recycles its cytoplasmic contents as nutritional rewards for its leafcutter ant farmers

Leafcutter ants farm a fungal cultivar (Leucoagaricus gongylophorus) that converts inedible vegetation into food that sustains colonies with up to millions of workers. Analogous to edible fruits of crops domesticated by humans, L. gongylophorus has evolved specialized nutritional rewards--swollen hyphal cells called gongylidia that package metabolites ingested by ant farmers. Yet, little is known about how gongylidia form, and thus how fungal physiology and ant provisioning interact to farming performance. We explored the mechanisms governing gongylidium formation using microscopy imaging of ant-cultivated fungus and controlled in vitro experiments with the cultivar grown in isolation from ant farmers. First, L. gongylophorus is polykaryotic (up to 17 haploid nuclei/cell) and our results suggest intracellular nucleus distributions govern gongylidium morphology with their absence in expanding edges arresting apical growth and their presence mediating complex branching patterns. Second, nanoscale imaging (SEM, TEM) shows that the cultivar recycles its own cellular material (e.g. cytosol, mitochondria) through a process called autophagy and stores the resulting metabolites in gongylidia. This autophagic pathway is further supported by gongylidium suppression when isolated fungal cultures are grown on media with autophagy inhibitors, and differential transcript expression (RNA-seq) analyses showing upregulation of multiple autophagy genes in gongylidia. We hypothesize that autophagic nutritional reward production is the ultimate cultivar service and reflects a higher-level organismality adaptation enabled by strict symmetric lifetime commitment between ant farmers and their fungal crop.

microbiology↗

Flavoceraceomyces (NOM. PROV.) (Irpicaceae, Basidiomycota), encompassing Ceraceomyces serpens and Ceriporia sulphuricola, and a new resupinate species, F. damiettense, found on Phoenix dactylifera (date palm) trunks in the Nile Delta of Egypt

The taxonomy of Polyporales is complicated by the variability in key morphological characters across families and genera, now being gradually resolved through molecular phylogenetic analyses. Here a new resupinate species, Flavoceraceomyces damiettense (NOM. PROV.) found on the decayed trunks of date palm (Phoenix dactylifera) trees in the fruit orchards of the Nile Delta region of Egypt is reported. Multigene phylogenetic analyses based on ITS, LSU, EF1, RPB1 and RPB2 loci place this species in Irpicaceae, and forming a distinct clade with Ceraceomyces serpens and Ceriporia sulphuricolor, which we also incorporate into a new genus Flavoceraceomyces (NOM. PROV.). The honey-yellow basidiomes with white margins and presence of crystal-encrusted hyphae in the hymenium and subiculum are distinctive features of Flavoceraceomyces (NOM. PROV.), despite variability in hymenium morphology and presence of clamp connections and cystidia, as noted for other genera within Irpicacae. F. damiettense is hitherto consistently associated with date palms killed by the red palm weevil Rhynchophorus ferrugineus, a highly damaging and invasive pest, recently spread to the Mediterranean region. F. damiettense causes rapid wood decay by a potentially unusual white-rot mechanism and may play a role in the damage caused by R. ferrugineus.

microbiology↗

Reclassification of Pterulaceae Corner (Basidiomycota: Agaricales) introducing the ant-associated genus Myrmecopterula gen. nov., Phaeopterula Henn. and the corticioid Radulomycetaceae fam. nov.

Pterulaceae was formally proposed to group six coralloid and dimitic genera [Actiniceps (=Dimorphocystis), Allantula, Deflexula, Parapterulicium, Pterula and Pterulicium]. Recent molecular studies have shown that some of the characters currently used in Pterulaceae Corner do not distinguish the genera. Actiniceps and Parapterulicium have been removed and a few other resupinate genera were added to the family. However, none of these studies intended to investigate the relationship between Pterulaceae genera. In this study, we generated 278 sequences from both newly collected and fungarium samples. Phylogenetic analyses support by morphological data allowed a reclassification of Pterulaceae where we propose the introduction of Myrmecopterula gen. nov. and Radulomycetaceae fam. nov., the reintroduction of Phaeopterula, the synonymisation of Deflexula in Pterulicium and 51 new combinations. Pterula is rendered polyphyletic requiring a reclassification; thus, it is split into Pterula, Myrmecopterula gen. nov., Pterulicium and Phaeopterula. Deflexula is recovered as paraphyletic alongside several Pterula species and Pterulicium, and is sunk into the latter genus. Phaeopterula is reintroduced to accommodate species with darker basidiomes. The neotropical Myrmecopterula gen. nov. forms a distinct clade adjacent to Pterula, and most members of this clade are associated with active or inactive attine ant nests. The resupinate genera Coronicium and Merulicium are recovered in a strongly supported clade close to Pterulicium. The other resupinate genera previously included in Pterulaceae, and which form basidiomes lacking cystidia and with monomitic hyphal structure (Radulomyces, Radulotubus and Aphanobasidium), are reclassified into Radulomycetaceae fam. nov. Allantula is still an enigmatic piece in this puzzle known only from the type specimen that requires molecular investigation. A key for the genera of Pterulaceae and Radulomycetaceae fam. nov. is provided here.

microbiology↗