Published: Syll. Fung. 5: 797 (1887)
Taxonomic status: This is a Inosperma.
Notes: Current name: Inosperma mutatum (Peck) Matheny & Esteve-Rav., in Matheny, Hobbs & Esteve-Raventós, Mycologia: 112 (1): 103 (2019) ["2020"]
Basionym: Agaricus mutatus Peck [as "Agaricus (Hebeloma) mutatus"] (1872)
Types: UNITED STATES: New York: Catskill Mountains (approx. 41.509°N, 74.926°W, alt. approx. 350 m a.s.l.) on boggy soil in woodland, Jul. 1870, C.H. Peck (Holotype. herbarium acc. no. NYS-F-002027, HJB1000263).UNITED STATES: New York: Catskill Mountains (approx. 41.509°N, 74.926°W, alt. approx. 350 m a.s.l.) on boggy soil in woodland, Jul. 1870, C.H. Peck (Holotype. herbarium acc. no. NYS-F-002028, HJB1000532).
Diagnosis: Pileus thin, firm, convex or broadly conical, gibbous or broadly umbonate, rough with squarrose fasciculate, floccose scales, which at length disappear except on the disk, dark brown: lamellae broad, close, rounded and very deeply emarginate behind, attached by the extreme upper part only, dark ferruginous brown, edge whitish; stem slender, equal, solid, firm, floccose-scaly, often curved at the base, colored like the pileus; spores elliptical, 1/2500' long. Plant 2'-3' high, pileus 6"-12" broad, stem 1" thick. Damp ground in woods. Catskill mountains. July. The changed appearance produced by the disappearance of the scales suggests the specific name.
Commentary: The taxon was originally described by Peck (1872) as Agaricus (Hebeloma) mutatus, recombined as Inocybe mutata by Massee (1904) and recently recombined as Inosperma mutatum (Matheny et al. 2020). The spores are smooth walled, slightly reniform, on average 10.5 × 5.2 μm, the cystidia are clavate to pyriform, sometimes utriform. The morphology supports the recombination as first observed by Massee (1904) and subsequently Kauffman (1924). Additionally, an ITS sequence has been generated from the holotype, further supporting the recombination. None of the ITS sequences published under the name of Is. mutatum (or I. mutata) appears to be conspecific with the type. Rather, it appears that Is. apiostomum may be conspecific with Is. mutatum in which case Is. mutatum would have priority.
All current species: aanenii | adherens | aestivale | albidulum | alboerumpens | albomarginatum | album | alpinicola | alpinum | ambustiterranum | aminophilum | ammophilum | angelesiense | angustilamellatum | anthracophilum | arcticum | asperosporum | aurantioumbrinum | australe | avellaneum | bellotianum | birrus | bulbiferum | catalaunicum | caulocystidiosum | cavipes | celatum | cinnamomeum | circinans | cistophilum | citrisporum | cohaerens | colvinii | crustuliniforme | cylindrosporum | danicum | discomorbidum | duracinoides | eburneum | echinosporum | erebium | erumpens | excedens | flavidifolium | fuscatum | fusisporum | geminatum | grandisporum | griseopruinatum | harperi | helodes | hiemale | ifeleletorum | immutabile | incarnatulum | indicum | ingratum | ischnostylum | islandicum | kelloggense | lactariolens | laetitiae | laterinum | leucosarx | limbatum | lindae | louiseae | luchuense | luteicystidiatum | lutense | mackinawense | magnicystidiatum | marginatulum | matritense | mediorufum | melleum | mesophaeum | minus | monticola | nanum | nauseosum | naviculosporum | neurophyllum | nigellum | nitidum | nothofagetorum | odoratissimum | olympianum | pallidolabiatum | paludicola | parcivelum | parvicystidiatum | parvisporum | pascuense | perexiguum | plesiocistum | populinum | porphyrosporum | praeolidum | psammophilum | pseudoamarescens | pseudofragilipes | pubescens | pumilum | pungens | pusillum | quercetorum | radicans | radicosoides | radicosum | rostratum | sacchariolens | sagarae | salicicola | sarcophyllum | serratum | sinapizans | sordescens | sordidulum | spetsbergense | sporadicum | subaustrale | subconcolor | subfastibile | subtortum | syrjense | theobrominum | vaccinum | velatum | velutipes | vesterholtii | victoriense | vinosophyllum | viscidissimum | youngii
All related names: aberrans | aeruginosum | affine | agglutinatum | aggregatum | alabamense | alachuanum | albiceps | albidocortinatum | albidocortinatus | albipes | albocolossum | albocrenulatum | albocrenulatus | alvarense | amarellum | angustifolium | angustifolius | angustilamellata | angustispermum | angustisporium | apolectum | apolectus | appendiculatum | aprile | arenicolor | arenosum | argentinum | ascophorus | asperulatum | atrifulvifolium | atrobrunneum | atrosanguineum | augusti | aurantiellum | austroamericanum | bakeri | barrowsii | bellotianus | bicoloratum | bingolense | birra | boulderense | broadwayi | bruchetii | brunneifolium | brunneodiscum | brunneomaculatum | bryogenes | bubalinum | bulbaceum | bulbosum | busporus | caespitosum | californicum | calvinii | calyptrosporum | canariense | candidipes | capniocephalum | capniocephalus | catervarium | catervarius | cerussatum | ceskae | chapmaniae | chlorophyllum | cinchonense | cinereostipes | cinereum | claviceps | clavuligera | clavuligerum | clavulipes | clavus | coarctatum | coarctatus | collariatum | colossus | commune | communis | coniferarum | coprophilum | corrugatum | cortinarioides | crassicystidiatum | crassipes | crassum | crassus | cremeopallidum | cremeum | crustuliniformis | cubense | dasypus | decoratus | deflectens | denigricans | diffracta | diffractum | diffractus | discomorbida | discomorbidus | dissiliens | domardiana | domardianum | dryophilum | dunense | earlei | edule | edulis | edurum | elata | elatellum | elatellus | elatum | elatus | ellipsoideosporium | erebia | erysibodes | evensoniae | exalbidum | exalbidus | exiguifolium | fagicola | fallax | farinaceum | fastibile | fastibilis | favrei | felipponei | felleum | fimbriatus | fimicola | firma | firmum | firmus | flaccidum | flammuloides | flavescens | flavidifolia | flavum | flexuosipes | floridanum | foedatum | fragilior | fragilipes | fragilius | fragrans | fragrantissimum | frenchii | funariophilum | fuscodiscum | fuscodiscus | fuscostipes | fusiformiradicatum | fusiformiradicatus | fusipes | gigaspermum | gigaspora | gigasporum | gigasporus | glabrescens | glutinosa | glutinosum | glutinosus | gomezii | gracile | gregariiforme | gregarium | griseocanescens | griseocanum | griseoscabrosum | griseoscabrosus | griseovelatum | griseum | griseus | groegeri | helvolescens | hemisphaericum | herrmanniae | hesleri | hetieri | holophaea | hormanii | hortense | horticola | hudsoniatum | huijsmaniana | humile | humosum | hydrocybeoides | hygrophilum | idahoense | igneum | ignobile | ignobilis | illicitum | illicitus | imbecillis | incognitum | indecisum | indica | infidum | infidus | insigne | ischnostylus | juneauense | kalmicola | kammala | kanouseae | kauffmanii | kemptoniae | khogianum | kirtonii | kuehneri | lacteocoffeatum | laevatum | laevatus | lamelliconfertum | latericolor | laterinus | lateritium | latifolium | latisporum | laursenii | levisporum | levyanum | lignicolum | limacinum | lindrothii | litoreum | littenii | longicauda | longicaudum | longicaudus | longisporum | lubriciceps | lucidum | lugens | lundqvistii | luteobrunneum | lutescentipes | luteum | macrosporum | maderaspatana | magnimamma | majale | malenconii | mammillatum | mammosum | maritinum | medianum | medianus | mediterranea | mediterraneum | megacarpum | mentiens | mesophaea | mesophaeus | micropyramis | microspora | microsporum | milleri | miserum | mitrata | mitratum | mitratus | montanum | montanus | moseri | mussiva | mussivum | mussivus | mutatum | mutatus | naucorioides | naufragum | naufragus | nauseosus | neerlandica | nigricans | nigromaculatum | nudipes | oblongisporum | obscurum | occidentale | ochraceum | ochroalbidum | octavii | oculatum | odini | odoratissimus | odoratum | olidum | olidus | ollaliense | oregonense | oreophilum | ossa | pallescens | pallida | pallidifolium | pallidoargillaceum | pallidoluctuosum | pallidomarginatum | pallidomarginatus | pallidum | palustre | pamphiliense | parvifructum | parvifructus | patriciae | peckii | perangustisporium | perfarinaceum | perigoense | permollis | perpallidum | perplexum | petiginosum | petiginosus | petrakii | piceicola | pinetorum | pitkinense | platense | polare | politum | porcatosporum | praecaespitosum | praecox | praefarinaceum | praefelleum | praefinitum | praefinitus | praelatifolium | praeviscidum | proletaria | proximum | psammicola | psamminum | psamminus | pseudofastibile | pseudomesophaeum | pseudopunctatum | pseudostrophosum | pudica | pumiloides | punctata | punctatiforme | punctatum | punctatus | pyrophilum | pyrrholepidum | pyrrholepis | queletii | radicatum | radicatus | radicosa | radicosus | remyi | repandum | repandus | riparium | rivulosum | robustum | ruber | rubrofuscum | rubrum | rufosporum | salmonense | sambucinum | sambucinus | sanjuanense | sarcophyllus | scabella | scabellum | senatum | senescens | sericipes | siegelii | siennaecolor | simile | sinapiolens | sinuosa | sinuosum | sinuosus | smithii | sociale | solheimii | sordidulus | sordidum | splendens | spoliatum | spoliatus | squamulosum | stanleyense | stellatosporum | stellatosporus | stenocystis | sterile | sterilis | sterlingii | strophosum | strophosus | suaveolens | subannulatum | subargillaceum | subboreale | subcaespitosum | subcapitatum | subcollariatum | subcollariatus | subfastigiatum | subhepaticum | subincarnatum | sublamellatum | submelinoides | subochracea | subochraceum | subochraceus | subplatense | subrimosum | subrubescens | subsacchariolens | subsaponaceum | subsaponaceus | subscambum | subscambus | substrophosum | subtestaceum | subtestaceus | subumbrinum | subvatricosoides | subvictoriense | subviolaceum | subzonatum | subzonatus | sulcatum | sulcatus | syrjensis | sztoczekii | tenuifolium | termitaria | testacea | testaceum | testaceus | texanum | thomasianum | thomasianus | tomentosum | tomoeae | tortuosum | tortuosus | tottenii | trachysporum | trinidadense | truncatum | truncatus | tumidulum | tumidulus | umbellatum | urbanicola | utahense | vatricosa | vatricosoides | vatricosum | vatricosus | vejlense | velenovskyi | venifer | veniferum | vernale | verrucispora | verruculosum | versipelle | versipellis | victoriae | vinaceogriseum | vinaceoumbrinum | violascens | virgatum | viscidissima | viscidissimus | weberi | wells-kemptoniae | wellsiae | westraliense | xerophilum | zsigmondyi