Litsea, a non-monophyletic group of the tribe Laureae (Lauraceae), plays important roles in the tropical and subtropical forests of Asia, Australia, Central and North America, and the islands of the Pacific. However, intergeneric relationships between Litsea and Laurus, Lindera, Parasassafras and Sinosassafras of the tribe Laureae remain unresolved. In this study, we present phylogenetic analyses of seven newly sequenced Litsea plastomes, together with 47 Laureae plastomes obtained from public databases, representing six genera of the Laureae. Our results highlight two highly supported monophyletic groups of Litsea taxa. One is composed of 16 Litsea taxa and two Lindera taxa. The 18 plastomes of these taxa were further compared for their gene structure, codon usage, contraction and expansion of inverted repeats, sequence repeats, divergence hotspots, and gene evolution. The complete plastome size of newly sequenced taxa varied between 152,377 bp (Litsea auriculata) and 154,117 bp (Litsea pierrei). Seven of the 16 Litsea plastomes have a pair of insertions in the IRa (trnL-trnH) and IRb (ycf2) regions. The 18 plastomes of Litsea and Lindera taxa exhibit similar gene features, codon usage, oligonucleotide repeats, and inverted repeat dynamics. The codons with the highest frequency among these taxa favored A/T endings and each of these plastomes had nine divergence hotspots, which are located in the same regions. We also identified six protein coding genes (accD, ndhJ, rbcL, rpoC2, ycf1 and ycf2) under positive selection in Litsea; these genes may play important roles in adaptation of Litsea species to various environments.

Zhujiangyuan Nature Reserve, located in Qujing City, Yunnan Province, China, is reported with high fauna and floral diversity, while the fungal diversity of the region is poorly documented. During the summer season in 2023, decaying wood-inhabiting microfungi were collected from different microhabitats. The novel species were identified based on morphological characteristics and phylogenetic analyses (based on combined datasets of ITS, LSU, SSU, tef1-α, and rpb2 regions). Two species belong to Dothideomycetes (viz., Spegazzinia zhujiangyuanensissp. nov. and Phaeoseptum zhujiangyuanensesp. nov. in Pleosporales) while the other one resides in Sordariomycetes (Synnemasporella faniisp. nov. in Diaporthales). The results are in conformity with the earlier studies that predicted higher fungal diversity in this region.

Morphological comparisons and multi locus phylogenetic analyses (base on the combined genes of ITS, LSU, rpb2 and tub) demonstrated that three new saprobic taxa isolated from bamboo belong to Cainiaceae. These taxa comprise a novel genus Paramphibambusa (P. bambusicolasp. nov.) and two new species, Arecophila xishuangbannaensis and A. zhaotongensis. The three new taxa belong to Cainiaceae (Xylariales, Sordariomycetes) a poorly studied family, which now comprises eight genera. Paramphibambusa can be distinguished from other Cainiaceae genera in having ascomata with a neck and ascospores lacking longitudinal striation, germ slits or germ pores. The two new Arecophila species clustered in a clade with Arecophila sp. and A. bambusae. Detailed morphological descriptions, illustrations, and an updated phylogenetic tree are provided for the new taxa.

The genus Strobilomyces, representing a diverse and widespread group of ectomycorrhizal mushroom-forming fungi, plays a crucial ecological and economical role. However, until now, a comprehensive description of its mitochondrial genome (mitogenome) has been lacking. In our current study, we have successfully assembled and analysed the mitogenomes of five Strobilomyces species. These mitogenomes span a range from 35,618 base pairs (bp) to 42,088 bp, exhibiting a higher nucleotide abundance of AT compared to GC. All five mitogenomes harbour 14 conserved protein-coding genes (PCGs), two ribosomal RNAs (rRNAs) and 24 transfer RNAs (tRNAs). Notably, the overall ratio of Ka/Ks for all PCGs was found to be less than 1.0, indicating that these genes have undergone purifying selection during evolution. Intriguingly, the mitogenomic comparison revealed two instances of gene re-arrangement, which were directly linked to the geographical distribution of the Strobilomyces species. The concatenated mitochondrial PCGs (mtPCGs) and nuclear ribosomal DNA (nrDNA) phylogenies displayed a robust congruent topology at the family level. Specifically, the Strobilomyces species clustered together and formed sister relationship with other Boletaceae species in the mtPCGs tree. In contrast, the Strobilomyces species grouped at the base of the nrDNA tree when concerning Boletaceae. This study represents the first report on the mitogenomes of the Strobilomyces genus, providing valuable insights into fungal evolution within Boletales.

In recent years, there has been a concerted effort to delve into the realms of species diversity, taxonomy, and phylogeny within the fungal kingdom, yielding a plethora of newfound insights (Wu et ...