Circumscription and typification of sphagnicolous omphalinoid species of Arrhenia (Hygrophoraceae) in Newfoundland and Labrador: three obligate and one facultative species

Abstract Molecular studies of sphagnicolous arrhenias in Newfoundland and Labrador (NL) revealed four clades Arrhenia , three obligate (two scaly capped one smooth-capped) facultative (smooth-capped) sphagnophiles. Critical nomenclatural review 16 names used for omphalinoid taxa the past left five suitable to apply this group. One sphagnophilic clade contained type Arr. gerardiana other, Clitocybe var. fusca ; latter we introduce as novel species bigelowii . It differed from first by longer spores a darkening reaction 10% collections. The smooth-capped third types Agaricus telmatiaeus Omphalina fusconigra recombined it telmatiaea This is darkest group, with more northern distribution NL. sphagnophile was identified philonotis lighter also Unexpectedly, collected an unidentified facultatively O. pyxidata complex. All are distributed both Europe North America. We describe each sequenced type, providing new material where needed. Overall, study adds sequences over 80 specimens two existing GenBank when began 2006, 11 several other arrhenias.