Orbilia blumenaviensis and its Arthrobotrys anamorph

Abstract

A member of the nematophagous anamorph genus Arthrobotrys was isolated from its teleomorph Orbilia blumenaviensis comb. nov. (= Orbilia fici), a species closely related to O. auricolor but deviating in having lanceolate paraphyses.In the presence of nematodes, the anamorph forms threedimensional adhesive networks. A trimorphism in its conidia was observed which vary in shape and number of septa. In the first isolate, two types of heteropolar conidia were obtained. These differ markedly from the type strain of A. vermicola, which forms mainly homopolar (fusoid) conidia. In a further ascospore isolate of O. blumenaviensis, however, mainly fusoid conidia referable to A. vermicola occurred. Combining morphological and phylogenetic analysis, we conclude that these isolates with differently shaped conidia and/or differences in the ITS rDNA (ca. 2-4%) belong to a single anamorph species, A. vermicola. Both teleomorph and anamorph are illustrated and described.

Fungal species concepts in the genomics era

“…Previously grouped to the large phylum "Fungi Imperfecti" for organisms where only asexual reproductive structure was observed, each organism was given an anamorphic species name. If the sexual form was later discovered, an additional teleomorphic species name and classification would be provided for the same organisms, often in different genera, family, or even higher taxonomic rank (e.g., Cai et al 2011;Qiao et al 2011;Kwon-Chung et al 2017). Given sufficient time, the diverging populations may accumulate mutations that impact most or all types of traits, causing each individual sub-population to have its own distinct morphological, ecological, and reproductive features.…”

“…As such, over the last 200 years, taxonomists working with different groups of fungi have diverged in the characters that they have used to identify and describe different groups of fungi, contributing to making broad comparisons among different fungal groups difficult. For example, as mentioned briefly above, most fungal taxonomists working on microscopic fungi such as yeasts tend to use traits similar to those in prokaryotes, including micromorphological traits, substrate utilization patterns, DNA-DNA hybridization, DNA sequences at the ribosomal RNA gene cluster, and mating and meiotic progeny production and viability (e.g., Kurtzman et al 2011;Qiao et al 2011;Hagen et al 2015;Zheng et al 2019). In contrast, those working on macrofungi such as mushrooms often rely on a specific set of morphological traits such as the shape, size, and colour of various parts of mushroom fruiting bodies, the size and shape of spores and spore-production tissues, and more recently DNA sequences at one or multiple gene loci (Singer 1986;Wu et al 2016).…”

2 Pezizomycotina: Pezizomycetes, Orbiliomycetes

“…Of particular note is the reliance on fresh, living material (Baral 1992). There has been a burst of activity focusing on the description of teleomorphic taxa and associated anamorphs (e.g., Kohlmeyer et al 1998;Liu et al 2005aLiu et al , b, 2006Mo et al 2005;Pfister 1994;Pfister and Liftik 1995;Qiao et al 2011;Qin et al 2010;Su et al 2011;Tanabe et al 1999;Webster et al 1998;Wu et al 2007;Yang and Liu 2005;Yu et al 2007aYu et al , b, c, 2011Zhang et al 2007), and in this work there has been an intense interest in the diversity and functional morphology of the anamorphic states. This is particularly the case regarding those that capture nematodes, i.e., species referred to Arthrobotrys and allied form genera.…”

“…Anamorphs can provide some useful information on the biology and ecology of these fungi. Those that have been demonstrated to trap nematodes and other invertebrates fall into the following genera: Arthrobotrys (Li et al 2005;Mo et al 2005;Pfister 1994Pfister , 1997Pfister and Liftik 1995;Qiao et al 2011), Drechslerella (Li et al 2005), Dwayaangam (Barron 1991), Gamsylella, known only in its anamorphic state , Lecophagus (Tanabe et al 1999), and Monacrosporium (Li et al 2005;Pfister 1997). There remains debate about the application of some of these names.…”

New records and new distribution of known species in the family Orbiliaceae from China

“…Besides a new genus Pseudorbilia (Zhang et al, 2007), eight new Orbilia species, eight new Orbilia records and three new Hyalorbilia species were reported from China (Wu et al, 2007;Zhang et al, 2009;Su et al, 2010). Together with anamorphs or single, other scattered new species were reported (Zhang et al, 2006;Liu et al, 2005a, b;Mo et al, 2005a,b;Yu et al, 2006Yu et al, , 2007aYu et al, 2009a,b;Li et al, 2009;Qiao et al, 2011). In Chinese publication, Liu et al (2007a, b) and Guo et al (2007)…”