The phylogenetic position of poroid Hymenochaetaceae (Hymenochaetales, Basidiomycota) from Patagonia, Argentina

Abstract

Six poroid Hymenochaetaceae from Patagonia, Argentina, were studied phylogenetically with nuc rDNA internal transcribed spacer (ITS) and partial 28S rDNA sequences, together with morphological data. Two new genera and a new species are introduced as well as two new combinations proposed. Arambarria destruens gen. et sp. nov. is proposed for a taxon fruiting on fallen or standing, dead Diostea juncea and Lomatia hirsuta and previously recorded erroneously as Inocutis jamaicensis; it is distinguished by annual, effused to effused-reflexed basidiomes forming pilei, a monomitic hyphal system, thick-walled and yellowish basidiospores (brownish chestnut in potassium hydroxide solution), lack of a granular core in the context and lack of setoid elements. Nothophellinus gen. nov. is proposed to accommodate Phellinus andinopatagonicus, the main white wood-rotting polypore of standing Nothofagus pumilio and also an important wood-decayer of other Nothofagus species from southern Argentina and Chile. It is morphologically similar to Phellopilus (type species P. nigrolimitatus) but differs by lacking setae. The new combinations Pseudoinonotus crustosus and Phellinopsis andina are proposed for Inonotus crustosus and Phellinus andinus, respectively. Phellinus livescens, which decays the sapwood of several standing Nothofagus species, is closely related to Phellinus uncisetus, a Neotropical species related to Fomitiporia; for the time being P. livescens is retained in Phellinus sensu lato. An unidentified taxon responsible for a white heart-rot in living Austrocedrus chilensis grouped with Phellinus caryophyllii and Fulvifomes inermis, but its generic affinities remain ambiguous. Transmission electron microscopy studies confirm this unidentified taxon has an imperforate parenthesome, which is typical of the Hymenochaetaceae.

A discussion on the genus Fomitiporella (Hymenochaetaceae, Hymenochaetales) and first record of F. americana from southern South America

“… Arambarria Rajchenb. & Pildain ( Rajchenberg et al 2015 , Pildain et al 2017 ) appeared distant from the former and is monomitic throughout the basidiome and lacks a granular core in context. The three genera contrast with the fully dimitic Fomitiporella species.…”

“…Strains isolated from the white heart-rot found in standing Austrocedrus chilensis in Patagonia and previously determined as Hymenochaetaceae sp. ( Barroetaveña and Rajchenberg 1996 , Rajchenberg et al 2015 ) were also incorporated, as well as a new strain of F. inermis from the USA. See Suppl.…”

“…ITS1, ITS2 and the intervening 5.8S RNA gene; further referred as ITS) with ITS5-ITS4 ( White et al 1990 ). The PCR conditions were described in Rajchenberg et al (2015) : 95 °C for 2 min, 30 cycles of 94 °C for 30 s, 52 °C for 30 s, 72 °C for 1 min, followed by 72 °C for 8 min. The amplified fragments were purified and sequenced at the DNA Synthesis and Sequencing Facility, Macrogen (Seoul, Korea).…”

“…Their studies, though, did neither incorporate nor discuss the positions of several genera described previously, namely Arambarria Rajchenb. & Pildain, Inocutis Fiasson & Niemelä and Phellinotus Drechsler-Santos, Robledo & Rajchenb., published in works that showed the complex relations within the members of “ Phellinotus clade”, where Fomitiporella is included (Wagner and Fisher 2002, Rajchenberg et al 2015 , Drechsler-Santos et al 2016 , Pildain et al 2017 ).…”

“…Studies on the wood-rots ( Barroetaveña and Rajchenberg 1996 ) and search of the associated wood-rotting mycobiota ( Rajchenberg 2002 ) were produced but were unsuccessful in identifying the WHR causing agent. Rajchenberg et al (2015) included strains of this WHR fungus in their phylogenetic study of poroid Hymenochaetaceae from Patagonia. These strains clustered in a group of species that included Fomitiporella caryophylli (Racib.)…”