No abstract

Riqueza y endemismo de las especies de Clavariadelphus (Clavariadelphaceae: Gomphales) en la Faja Volcánica Transmexicana Richness and endemism of the species of Clavariadelphus (Clavariadelphaceae: Gomphales) in the Trans-Mexican Volcanic Belt

In this study, we included for the first time three Mexican Gomphaceae species in a molecular phylogeny. These species were described as members of the genus Gomphus, despite their tropical and subtropical habitat. We undertook a molecular analysis using the atp6 and SSU mitochondrial loci and nuclear ribosomal LSU. Our analysis showed that the three species studied are better included as members of Gloeocantharellus. In this study, we are suggesting three new combinations: Gloeocantharellus albidocarneus, G. calakmulensis and G. pleurobrunnescens.

The distribution and endemicity patterns of Gomphales in Mexico are analyzed here for the first time. Richness and corrected endemism were obtained from a dataset of 3,483 records for 97 species, using a cell-grid system of one degree per side. The central region of Mexico (Tlaxcala, Veracruz, Hidalgo and Estado de México states), which includes most of the Trans-Mexican Volcanic Belt and Sierra Madre Oriental biogeographic provinces, had the highest richness values, but Mexican areas in the Pacific Coast (Jalisco and Michoacán states) and southeastern Mexico (Oaxaca and Chiapas states) had the most distinctive composition, as measured by the corrected endemism index. Two main distributional patterns were recovered: a) montane: at elevations above 1000 m on coniferous, pine-oak, oak and cloud forests, typified by the presence of species of Ramaria and Clavariadelphus, b) lowlands: at elevations below 1000 m mainly in evergreen, rainforest and deciduous tropical forests characterized by the presence of four tropical species of Lentaria, two tropical species of Gomphus endemic to Mexico, and four tropical species of Phaeoclavulina. The eight species of Gomphales endemic to Mexico have very restricted distribution, mostly in non-protected areas, and are not considered under special protection programs. The present contribution delineates general patterns of distribution for the Gomphales, and documents its diversity and endemism in Mexico.

The geographic distribution of 10 genera and 71 species of the order Gomphales in Mexico is analysed using the panbiogeographic approach. This allows us to gain a better understanding of distribution patterns and to propose conservation areas. We compiled a database containing 3,484 occurrence records for Gomphales from taxonomic literature, herbarium specimens, institutional databases and field collections. Using this database, we obtained individual tracks for species of Gomphales. From the comparison and intersection of the 43 individual tracks, we identified six generalised tracks and 10 panbiogeographic nodes. Most of the generalised tracks were associated with the main Mexican mountains systems. Accordingly, panbiogeographic nodes were mainly located along the Trans-Mexican Volcanic Belt. Most nodes coincided with previously recognised nodes in other taxa, and almost half were located within Natural Protected Areas. Based on our results, we suggest that future molecular studies are necessary in order to define with precision species limits, which together with regional species inventories in tropical areas will significantly improve our understanding of fungal distributions. An integrative discussion regarding conservation criteria, and how to integrate endemic species on conservation programs is also included.