Hymenophyllum

Hymenophyllum is a genus of ferns in the family Hymenophyllaceae. Its name means "membranous leaf", referring to the very thin translucent tissue of the fronds, which gives rise to the common name filmy fern for this and other thin-leaved ferns. The leaves are generally only one cell thick and lack stomata, making them vulnerable to desiccation. Consequently, they are found only in very humid areas, such as in moist forests and among sheltered rocks. They are small and easy to overlook.

Species
, World Ferns accepted the following extant species:


 * Hymenophyllum abruptum Hook.
 * Hymenophyllum acanthoides (Bosch) Rosenst.
 * Hymenophyllum acutum (C.Presl) Ebihara & K.Iwats.
 * Hymenophyllum adiantoides Bosch
 * Hymenophyllum aeruginosum (Poir.) Carmich.
 * Hymenophyllum alveolatum C.Chr.
 * Hymenophyllum amabile Morton
 * Hymenophyllum andinum Bosch
 * Hymenophyllum angulosum Christ
 * Hymenophyllum angustum Bosch
 * Hymenophyllum antillense (Jenman) Jenman
 * Hymenophyllum apiculatum Mett. ex Kuhn
 * Hymenophyllum applanatum (A.M.Gray & R.G.Williams) Ebihara & K.Iwats.
 * Hymenophyllum apteryx M.Kessler & Sundue
 * Hymenophyllum archboldii (Copel.) C.V.Morton
 * Hymenophyllum armstrongii (Baker) Kuhn
 * Hymenophyllum asplenioides (Sw.) Sw.
 * Hymenophyllum assurgens M.Kessler & A.R.Sm.
 * Hymenophyllum australe Willd.
 * Hymenophyllum axillare Sw.
 * Hymenophyllum badium Hook. & Grev.
 * Hymenophyllum baileyanum Domin
 * Hymenophyllum balfourii Baker
 * Hymenophyllum barbatum (Bosch) Baker
 * Hymenophyllum bartlettii (Copel.) C.V.Morton
 * Hymenophyllum batuense Rosenst.
 * Hymenophyllum bicolanum Copel.
 * Hymenophyllum bivalve (G.Forst.) Sw.
 * Hymenophyllum blandum Racib.
 * Hymenophyllum bontocense Copel.
 * Hymenophyllum brachyglossum A.Braun ex Kunze
 * Hymenophyllum brachypus Sodiro
 * Hymenophyllum braithwaitei Ebihara & K.Iwats.
 * Hymenophyllum brassii C.Chr.
 * Hymenophyllum brevifrons Kunze
 * Hymenophyllum brevistipes Liebm.
 * Hymenophyllum bryoides C.W.Chen, Ebihara & K.Y.Cheng
 * Hymenophyllum bryophilum C.Chr.
 * Hymenophyllum caespitosum Gaudich.
 * Hymenophyllum caparaoense Brade
 * Hymenophyllum capense Schrad.
 * Hymenophyllum capillaceum Roxb.
 * Hymenophyllum capillare Desv.
 * Hymenophyllum capurroi de la Sota
 * Hymenophyllum cardunculus C.Chr.
 * Hymenophyllum caudiculatum Mart.
 * Hymenophyllum chamaecyparicola T.C.Hsu & Z.X.Chang
 * Hymenophyllum cocosense A.Rojas
 * Hymenophyllum compactum Bonap.
 * Hymenophyllum consanguineum C.V.Morton
 * Hymenophyllum copelandii C.V.Morton
 * Hymenophyllum cordobense (Hieron.) C.Larsen & Arana
 * Hymenophyllum corrugatum Christ
 * Hymenophyllum crassipetiolatum Stolze
 * Hymenophyllum crispatoalatum Hayata
 * Hymenophyllum crispatum Wall. ex Hook. & Grev.
 * Hymenophyllum crispum Kunth
 * Hymenophyllum cristatum Hook. & Grev.
 * Hymenophyllum cruentum Cav.
 * Hymenophyllum cuneatum Kunze
 * Hymenophyllum cupressiforme Labill.
 * Hymenophyllum darwinii Hook.fil.
 * Hymenophyllum delicatulum Sehnem
 * Hymenophyllum deltoideum C.Chr.
 * Hymenophyllum demissum (G.Forst.) Sw.
 * Hymenophyllum densipilosum A.Rojas
 * Hymenophyllum dentatum Cav.
 * Hymenophyllum denticulatum Sw.
 * Hymenophyllum dependens C.V.Morton
 * Hymenophyllum deplanchei Mett. ex Kuhn
 * Hymenophyllum devolii M.J.Lai
 * Hymenophyllum dicranotrichum (C.Presl) Sadeb.
 * Hymenophyllum digitatum (Sw.) Fosberg
 * Hymenophyllum dilatatum (G.Forst.) Sw.
 * Hymenophyllum dimidiatum Mett. ex Kuhn
 * Hymenophyllum diversilobum (C.Presl) Fée
 * Hymenophyllum eboracense Croxall
 * Hymenophyllum ectocarpon Fée
 * Hymenophyllum edanoi (Copel.) C.V.Morton
 * Hymenophyllum edentulum (Bosch) C.Chr.
 * Hymenophyllum elbertii Rosenst.
 * Hymenophyllum elegans Spreng.
 * Hymenophyllum elongatum J.W.Grimes
 * Hymenophyllum emarginatum Sw.
 * Hymenophyllum exquisitum T.C.Hsu & Y.S.Chao
 * Hymenophyllum exsertum Wall. ex Hook.
 * Hymenophyllum falklandicum Baker
 * Hymenophyllum farallonense Hieron.
 * Hymenophyllum feejeense Brack.
 * Hymenophyllum fendlerianum Sturm
 * Hymenophyllum ferax Bosch
 * Hymenophyllum ferrugineum Colla
 * Hymenophyllum fimbriatum J.Sm.
 * Hymenophyllum firmum Alderw.
 * Hymenophyllum flabellatum Labill.
 * Hymenophyllum flexuosum A.Cunn.
 * Hymenophyllum foersteri Rosenst.
 * Hymenophyllum foxworthyi Copel.
 * Hymenophyllum fragile (Hedw.) Morton
 * Hymenophyllum francii (Christ) Ebihara & K.Iwats.
 * Hymenophyllum frankliniae Colenso
 * Hymenophyllum fuciforme Sw.
 * Hymenophyllum fucoides (Sw.) Sw.
 * Hymenophyllum fujisanense Nakai
 * Hymenophyllum fumarioides Bory ex Willd.
 * Hymenophyllum fuscum (Blume) Bosch
 * Hymenophyllum gardneri Bosch
 * Hymenophyllum geluense Rosenst.
 * Hymenophyllum glaziovii Baker
 * Hymenophyllum gorgoneum Copel.
 * Hymenophyllum gracilescens Domin
 * Hymenophyllum hallieri Rosenst.
 * Hymenophyllum hastatum A.Rojas
 * Hymenophyllum heimii Tardieu
 * Hymenophyllum helicoideum Sodiro
 * Hymenophyllum hemidimorphum R.C.Moran & B.Øllg.
 * Hymenophyllum hemipteron Rosenst.
 * Hymenophyllum herzogii Rosenst.
 * Hymenophyllum hieronymi (Brause) C.Chr.
 * Hymenophyllum hirsutum (L.) Sw.
 * Hymenophyllum hirtellum Sw.
 * Hymenophyllum holochilum (Bosch) C.Chr.
 * Hymenophyllum horizontale C.V.Morton
 * Hymenophyllum hosei Copel.
 * Hymenophyllum humbertii C.Chr.
 * Hymenophyllum humboldtianum E.Fourn.
 * Hymenophyllum hygrometricum (Poir.) Desv.
 * Hymenophyllum imbricatum Blume
 * Hymenophyllum inaequale (Poir.) Desv.
 * Hymenophyllum integrivalvatum C.Sánchez
 * Hymenophyllum interruptum Kunze
 * Hymenophyllum involucratum Copel.
 * Hymenophyllum ivohibense Tardieu
 * Hymenophyllum jamesonii Hook.
 * Hymenophyllum javanicum Spreng.
 * Hymenophyllum jimenezii A.R.Sm. & M.Kessler
 * Hymenophyllum johorense Holttum
 * Hymenophyllum junghuhnii Bosch
 * Hymenophyllum kaieteurum Jenman
 * Hymenophyllum karstenianum J.W.Sturm
 * Hymenophyllum kerianum Watts
 * Hymenophyllum klabatense Christ
 * Hymenophyllum krauseanum Phil.
 * Hymenophyllum kuhnii C.Chr.
 * Hymenophyllum l´herminieri Mett. ex Kuhn
 * Hymenophyllum lamellatum Stolze
 * Hymenophyllum laminatum Copel.
 * Hymenophyllum lanatum Fée
 * Hymenophyllum lanceolatum Hook. & Arn.
 * Hymenophyllum latifrons Bosch
 * Hymenophyllum latisorum M.Kessler & A.R.Sm.
 * Hymenophyllum laxum (Copel.) C.V.Morton
 * Hymenophyllum ledermannii Brause
 * Hymenophyllum lehmannii Hieron.
 * Hymenophyllum leptocarpum Copel.
 * Hymenophyllum leratii Rosenst.
 * Hymenophyllum levingei C.B.Clarke
 * Hymenophyllum lindenii Hook.
 * Hymenophyllum lineare (Sw.) Sw.
 * Hymenophyllum lobatoalatum Klotzsch
 * Hymenophyllum lobbii Moore ex Bosch
 * Hymenophyllum longifolium Alderw.
 * Hymenophyllum longissimum (Ching & P.S.Chiu) K.Iwats.
 * Hymenophyllum lyallii Hook.fil.
 * Hymenophyllum macgillivrayi (Baker) Copel.
 * Hymenophyllum macroglossum Bosch
 * Hymenophyllum macrosorum Alderw.
 * Hymenophyllum macrothecum Fée
 * Hymenophyllum maderense Gibby & Lovis
 * Hymenophyllum malingii (Hook.) Mett.
 * Hymenophyllum marginatum Hook. & Grev.
 * Hymenophyllum matthewsii Bosch
 * Hymenophyllum maxonii Christ ex Morton
 * Hymenophyllum megistocarpum (Copel.) C.V.Morton
 * Hymenophyllum melanosorum (Copel.) C.V.Morton
 * Hymenophyllum microcarpum Desv.
 * Hymenophyllum microchilum (Baker) C.Chr.
 * Hymenophyllum mikawanum (Seriz.) Seriz.
 * Hymenophyllum minimum A.Rich.
 * Hymenophyllum mirificum Morton
 * Hymenophyllum mnioides Baker
 * Hymenophyllum molle C.V.Morton
 * Hymenophyllum mortonianum Lellinger
 * Hymenophyllum mossambicense (Schelpe) Schippers
 * Hymenophyllum multialatum C.V.Morton
 * Hymenophyllum multicristatum A.Rojas
 * Hymenophyllum multifidum (G.Forst.) Sw.
 * Hymenophyllum myriocarpum Hook.
 * Hymenophyllum nahuelhuapiense Diem & J.S.Licht.
 * Hymenophyllum nanostellatum Lellinger
 * Hymenophyllum nanum Sodiro
 * Hymenophyllum neocaledonicum (C.Chr.) Rouhan & C.Del Rio
 * Hymenophyllum nephrophyllum Ebihara & K.Iwats.
 * Hymenophyllum nitiduloides Copel.
 * Hymenophyllum nitidulum (Bosch) Ebihara & K.Iwats.
 * Hymenophyllum novoguineense (Rosenst.) K.Iwats.
 * Hymenophyllum nutantifolium Alderw.
 * Hymenophyllum obtusum Hook. & Arn.
 * Hymenophyllum oligosorum Makino
 * Hymenophyllum ooides F.Muell. & Baker ex Baker
 * Hymenophyllum ovatum Copel.
 * Hymenophyllum pachydermicum Ces.
 * Hymenophyllum pallidum (Blume) Ebihara & K.Iwats.
 * Hymenophyllum palmatifidum (Müll.Berol.) Ebihara & K.Iwats.
 * Hymenophyllum paniculiflorum C.Presl
 * Hymenophyllum paniense Ebihara & K.Iwats.
 * Hymenophyllum pantotactum Alderw.
 * Hymenophyllum parallelocarpum Hayata
 * Hymenophyllum paucicarpum Jenman
 * Hymenophyllum pectinatum Cav.
 * Hymenophyllum peltatum (Poir.) Desv.
 * Hymenophyllum penangianum Matthew & Christ ex Christ
 * Hymenophyllum perparvulum Alderw.
 * Hymenophyllum perrieri Tardieu
 * Hymenophyllum pilosissimum C.Chr.
 * Hymenophyllum pilosum Alderw.
 * Hymenophyllum platylobum Bosch
 * Hymenophyllum plicatum Kaulf.
 * Hymenophyllum plumieri Hook. & Grev.
 * Hymenophyllum plumosum Kaulf.
 * Hymenophyllum pluviatile Perrie & Brownsey
 * Hymenophyllum pollemonianum Rosenst.
 * Hymenophyllum polyanthos (Sw.) Sw.
 * Hymenophyllum poolii Baker
 * Hymenophyllum praetervisum Christ
 * Hymenophyllum prionema Kunze
 * Hymenophyllum proctoris C.Sánchez
 * Hymenophyllum productum Kunze
 * Hymenophyllum protrusum Hook.
 * Hymenophyllum pulchellum Schltdl. & Cham.
 * Hymenophyllum pulcherrimum Colenso
 * Hymenophyllum pumilio Rosenst.
 * Hymenophyllum pumilum C.Moore
 * Hymenophyllum punctisorum Rosenst.
 * Hymenophyllum pyramidatum Desv.
 * Hymenophyllum quetrihuense Diem & J.S.Licht.
 * Hymenophyllum ramosii Copel.
 * Hymenophyllum rarum R.Br.
 * Hymenophyllum recurvum Gaudich.
 * Hymenophyllum reinwardtii Bosch
 * Hymenophyllum revolutum Colenso
 * Hymenophyllum ringens Christ
 * Hymenophyllum riukiuense Christ
 * Hymenophyllum rolandi-principis Rosenst.
 * Hymenophyllum roraimense C.V.Morton
 * Hymenophyllum rubellum Rosenst.
 * Hymenophyllum rufescens Kirk
 * Hymenophyllum rufifolium Alderw.
 * Hymenophyllum rufifrons Alderw.
 * Hymenophyllum rufum Fée
 * Hymenophyllum rugosum C.Chr. & Skottsb.
 * Hymenophyllum ruizianum (Klotzsch) Kunze
 * Hymenophyllum saenzianum L.D.Gómez
 * Hymenophyllum salakense Racib.
 * Hymenophyllum sampaioanum Brade & Rosenst.
 * Hymenophyllum sanguinolentum (G.Forst.) Sw.
 * Hymenophyllum scabrum A.Rich.
 * Hymenophyllum secundum Hook. & Grev.
 * Hymenophyllum semialatum T.C.Hsu
 * Hymenophyllum semiglabrum Rosenst.
 * Hymenophyllum senterreanum Dubuisson & Deblauwe
 * Hymenophyllum seramense K.Iwats., M.Kato & Ebihara
 * Hymenophyllum sericeum (Sw.) Sw.
 * Hymenophyllum serrulatum (C.Presl) C.Chr.
 * Hymenophyllum seselifolium C.Presl
 * Hymenophyllum sibthorpioides (Bory ex Willd.) Mett. ex Kuhn
 * Hymenophyllum sieberi (C.Presl) Bosch
 * Hymenophyllum silvaticum C.V.Morton
 * Hymenophyllum silveirae Christ
 * Hymenophyllum simonsianum Hook.
 * Hymenophyllum simplex C.V.Morton
 * Hymenophyllum sodiroi C.Chr.
 * Hymenophyllum soriemersum Rouhan & C.Del Rio
 * Hymenophyllum splendidum Bosch
 * Hymenophyllum stenocladum (Ching & P.S.Chiu) K.Iwats.
 * Hymenophyllum subdemissum Christ
 * Hymenophyllum subobtusum Rosenst.
 * Hymenophyllum subrigidum Christ
 * Hymenophyllum superbum Morton
 * Hymenophyllum taiwanense (Tagawa) C.V.Morton
 * Hymenophyllum talamancanum A.Rojas
 * Hymenophyllum taliabense Alderw.
 * Hymenophyllum tarapotense Stolze
 * Hymenophyllum tayloriae Farrar & Raine
 * Hymenophyllum tegularis (Desv.) Proctor & Lourteig
 * Hymenophyllum tenerum Bosch
 * Hymenophyllum thuidium Harr.
 * Hymenophyllum todjambuense Kjellb.
 * Hymenophyllum tomaniiviense (Brownlie) Ebihara & K.Iwats.
 * Hymenophyllum tomentosum Kunze
 * Hymenophyllum tortuosum Hook. & Grev.
 * Hymenophyllum trapezoidale Liebm.
 * Hymenophyllum treubii Racib.
 * Hymenophyllum triangulare Baker
 * Hymenophyllum trichomanoides Bosch
 * Hymenophyllum trichophorum (Alderw.) Ebihara & K.Iwats.
 * Hymenophyllum trichophyllum Kunth
 * Hymenophyllum trifoliatum (L.) Proctor & Lourteig
 * Hymenophyllum tunbrigense (L.) Sm.
 * Hymenophyllum turquinense C.Sánchez
 * Hymenophyllum umbratile Diem & J.S.Licht.
 * Hymenophyllum undulatum (Sw.) Sw.
 * Hymenophyllum urbanii Brause
 * Hymenophyllum valvatum Hook. & Grev.
 * Hymenophyllum verecundum Morton
 * Hymenophyllum veronicoides C.Chr.
 * Hymenophyllum vestitum (C.Presl) Bosch
 * Hymenophyllum viguieri Tardieu
 * Hymenophyllum villosum Colenso
 * Hymenophyllum vittatum Copel.
 * Hymenophyllum walleri Maiden & Betche
 * Hymenophyllum whitei Goy
 * Hymenophyllum wilsonii Hook.
 * Hymenophyllum wrightii Bosch

Extinct species include:
 * †Hymenophyllum axsmithii Pigg et al (Ypresian, Eocene Okanagan Highlands North America)