| Saccomorpha icmalea (Ach.) Clauzade & Cl. Roux = Placynthiella icmalea |
| Saccomorpha oligotropha (J.R. Laundon) Clauzade & Cl. Roux = Placynthiella
oligotropha |
| Saccomorpha uliginosa (Schrad.) Hafellner = Placynthiella uliginosa |
| Sagedia circumscripta (Taylor) Leight. = Peterjamesia circumscripta |
| Sagedia crassa (DC.) A. Massal. = Enterographa crassa |
| Sagedia marina Deakin = Stigmidium marinum |
| Sagediopsis tartarina (Nyl.) Vain. = Sagediopsis campsteriana |
| Sagiolechia rhexoblephara (Nyl.) Zahlbr. = Rhexophiale rhexoblephara |
| Sarcinulella banksiae B. Sutton & Alcorn [anamorph] = Anisomeridium polypori |
| Sarcogyne pruinosa = Sarcogyne regularis |
| Sarcogyne simplex (Davies) Nyl. = Polysporina simplex |
| Sarcopyrenia gibba = Sarcopyrenia gibba var. geisleri |
| Schaereria endocyanea (Stirt.) Hertel & Gotth. Schneid. = Schaereria fuscocinerea |
| Schaereria tenebrosa (Flot.) Hertel & Poelt = Schaereria fuscocinerea |
| Schasmaria sparassa (Ach.) Gray = Cladonia squamosa var. squamosa |
| Schismatomma abietinum (Humb.) A. Massal. = Schismatomma graphidioides |
| Schismatomma amylaceum (Ehrh. ex Pers) A. Massal. = Lecanographa amylacea |
| Schismatomma amylaceum var. candidum sensu Mudd (1861) = Lecanactis dilleniana |
| Schismatomma pericleum (Ach.) Branth & Rostr. = Schismatomma graphidioides |
| Schismatomma premneum (Ach.) Mudd = Cresponea premnea |
| Schismatomma premneum var. saxicolum Mudd = Cresponea premnea [on rock] |
| Schismatomma virgineum D. Hawksw. & P. James = Schismatomma cretaceum |
| Schizoma lichenodeum (Nyl.) Nyl. = Lempholemma radiatum |
| Schizoxylon corticolum Nyl = Bactrospora corticola |
| Sclerophora nivea (Hoffm.) Tibell = Sclerophora pallida |
| Sclerophytomyces circumscriptus (Taylor) Sparrius & P. James = Peterjamesia
circumscripta |
| Sclerophytomyces circumscriptus var. sorediatus Sparrius, P. James & M.A. Allen =
Peterjamesia sorediata |
| Sclerophyton circumscriptum (Taylor) Zahlbr. = Peterjamesia circumscripta |
| Sclerophyton circumscriptum f. dendrizum (Nyl.) Zahlbr. = Peterjamesia circumscripta |
| Sclerophytonomyces circumscriptus (Taylor) Sparrius & P. James = Peterjamesia
circumscripta |
| Sclerophytonomyces circumscriptus var. sorediatus Sparrius, P. James & M.A. Allen
= Peterjamesia sorediata |
| Scoliciosporum compactum = Scoliciosporum umbrinum |
| Scoliciosporum intrusum (Th. Fr.) Hafellner = Carbonea intrusa |
| Scoliciosporum vermiferum sensu Mudd = Scoliciosporum umbrinum |
| Scutula cristata (Leight.) Sacc. & D. Sacc. = Unguiculariopsis thallophila |
| Scutula episema (Nyl.) Zopf = Toninia episema |
| Scyphophora alcicornis (Lightf.) Gray = Cladonia foliacea |
| Scyphophora coccifera = Cladonia coccifera s. lat. |
| Scyphophorus cocciferus = Cladonia coccifera s. lat. |
| Scyphophorus cornutus (L.) Hook. = Cladonia cornuta |
| Scyphophorus deformis = Cladonia sulphurina |
| Scyphophorus filiformis sensu Hook. = Cladonia macilenta |
| Scyphophorus sparassus sensu Hook. = Cladonia squamosa s. lat. |
| Scytonema atrovirens (Dillwyn) C. Agardh = Ephebe lanata |
| Scytonema interruptum (Carmich. ex Hook.) Cooke = Dictyonema interruptum |
| Segestrella thelostoma (Ach. ex J. Harriman) Leight. = Thrombium thelostomum |
| Segestria lectissima Fr. = Porina lectissima |
| Segestria leptalea (Durieu & Mont.) R.C. Harris = Porina leptalea |
| Segestria mammillosa Th. Fr. = Porina mammillosa |
| Sirococcus lichenicola Keissl. = Bachmanniomyces uncialicola |
| Sirosiphon compactus (Agardh) Kütz. = non-lichenized Scytonema sp. {cyanobacterium} |
| Sirothecium lichenicola (Linds.) Keissl. = Vouauxiella lichenicola |
| Skyttea cruciata Sherwood, D. Hawksw. & Coppins = Rhymbocarpus cruciatus |
| Skyttea fusispora = Skyttea caesii |
| Skyttea lettaui (Grummann) D. Hawksw. = Unguiculariopsis lettaui |
| Skyttea refractiva Coppins = Unguiculariopsis refractiva |
| Skyttea tephromelarum Kalb & Hafellner = Skyttea elachistophora |
| Skyttea thallophila (P. Karst.) Sherwood & D. Hawksw. = Unguiculariopsis
thallophila |
| Solenopsora leucospeirea Nyl. = Solenopsora vulturiensis |
| Solorina limbata (Sommerf.) Mudd = Solorina spongiosa |
| Sorothelia squamarioides (Mudd) Zopf = Polycoccum squamarioides |
| Sphaeria cerinaria Mudd = Lichenodiplis lecanorae |
| Sphaeria gelidaria Mudd = Roselliniopsis gelidaria |
| Sphaeria leucostoma Bernh., non Pers:Fr. (1832) = Pertusaria leioplaca |
| Sphaeria sphincterica Sowerby = Sphinctrina turbinata |
| Sphaeria squamarioides Mudd = Polycoccum squamarioides |
| Sphaeromphale terebrata Mudd = Staurothele rupifraga |
| Sphaeromphale umbrina (Wahlenb.) Mudd = Staurothele fissa |
| Sphaerophoron = see Sphaerophorus |
| Sphaerophorus compressus Ach. = Bunodophoron melanocarpum |
| Sphaerophorus coralloides Pers. = Sphaerophorus globosus |
| Sphaerophorus coralloides var. caespitosus (DC.) Turner & Borrer = Sphaerophorus
fragilis |
| Sphaerophorus coralloides var. compressus Taylor = Bunodophoron melanocarpum |
| Sphaerophorus coralloides var. fragilis Taylor = Sphaerophorus fragilis |
| Sphaerophorus coralloides var. laxus Turner & Borrer = Sphaerophorus globosus |
| Sphaerophorus melanocarpus (Sw.) DC. = Bunodophoron melanocarpum |
| Sphaerulina chlorococca (Leight.) R. Sant. = Lauderlindsaya acroglypta |
| Sphaerulina chlorococca = Lauderlindsaya borreri |
| Sphaerulina corniculata (Wallr.) Vouaux = Obryzum corniculatum |
| Sphaerulina endococcoidea (Nyl.) Sacc. & D. Sacc. = Phaeospora rimosicola |
| Sphinctrina gelasinata = Sphinctrina turbinata |
| Sphinctrina kylemorensis (Larbal. ex Leight.) Cromb. = Sphinctrina leucopoda |
| Sphinctrina microcephala Nyl. = Sphinctrina tubiformis |
| Sphinctrina microcephala p.max.p. = Sphinctrina anglica |
| Sphinctrina pedata (Stenh.) R. Sant. = Sphinctrina leucopoda |
| Sphinctrina septata Leight. = Stenocybe septata |
| Sphinctrina trachelinum (Ach.) Leight. in Vize (1882) = Calicium salicinum |
| Sphinctrina tubaeformis A. Massal. = Sphinctrina tubiformis |
| Sphinctrina turbinata var. microcephala (Nyl.) Mudd = Sphinctrina tubiformis |
| Spiloma decolorans Turner & Borrer ex Sm. = Schismatomma decolorans |
| Spiloma dispersum Turner & Borrer ex Sm. = undetermined lignicolous fungus |
| Spiloma fuliginosum Turner & Borrer = application uncertain |
| Spiloma graphideorum Nyl., nom. illeg. = Milospium graphideorum |
| Spiloma gregarium (Weigel) Turner & Borrer = Arthonia cinnabarina |
| Spiloma microscopicum Turner & Borrer ex Sm. = undetermined lignicolous fungus |
| Spiloma murale Turner & Borrer ex Sm. = undetermined fungus |
| Spiloma nigrum Turner & Borrer = application uncertain |
| Spiloma punctatum Turner & Borrer ex Sm. = undetermined corticolous pycnidiate
lichen |
| Spiloma punctum Turner & Borrer = application uncertain |
| Spiloma tuberculosum Sm. = Porpidia tuberculosa |
| Spiloma variolosum Sm. = Opegrapha atra [infected with Milospium graphideorum] |
| Spiloma vitiligo Ach. = Xylographa vitiligo |
| Spilomela ascaridiella (Nyl.) D. Hawksw. = Spirographa fusisporella |
| Spilomela vermifera (Leight.) Keissl. = Spirographa fusisporella |
| Spilomium graphideorum Nyl. = Milospium graphideorum |
| Spilonema scoticum Nyl. = unidentified discomycete associated with cyanobacteria |
| Sporastatia cinerea (Schaer.) = Sporastatia polyspora |
| Squamaria affinis (Dicks.) Hook. = Pannaria rubiginosa |
| Squamaria caesia (Hoffm.) Hook. = Physcia caesia |
| Squamaria candelaria = Xanthoria candelaria |
| Squamaria candelaria sensu Hook. (1833) = Candelaria concolor |
| Squamaria candelaria var. polycarpa (Hoffm.) Hook. = Xanthoria polycarpa |
| Squamaria cartilaginea = Lecanora achariana |
| Squamaria circinata = Aspicilia radiosa |
| Squamaria circinatula (Nyl.) H. Olivier = Aspicilia radiosa |
| Squamaria clementei (Sm.) Hook. = Physcia clementei |
| Squamaria crassa (Huds.) DC. = Squamarina cartilaginea |
| Squamaria exomila (Stirt.) Walt. Watson comb. inval. = Lecanora crenulata |
| Squamaria gelida (L.) Hook. = Placopsis gelida |
| Squamaria gelida = Placopsis lambii |
| Squamaria hypnorum (Vahl) Hook. = Psoroma hypnorum |
| Squamaria lanuginosum Hook., nom. illeg. = Lepraria membranacea |
| Squamaria lentigera (Weber) DC. = Squamarina lentigera |
| Squamaria leucolepis (Wahlenb.) Hook. = Pannaria hookeri |
| Squamaria melanaspis (Ach.) Elenkin = Aspicilia melanaspis |
| Squamaria muralis (Schreb.) Elenkin = Lecanora muralis |
| Squamaria murorum sensu Hook. = Caloplaca aurantia |
| Squamaria muscorum (Gray) Hook. = Massalongia carnosa |
| Squamaria pruinosa (Chaub.) Duby = Lecanora pruinosa |
| Squamaria saxicola (Pollich) Hook. = Lecanora muralis |
| Squamaria saxicola var. areolata Leight. ex Mudd = Lecanora muralis |
| Squamaria subcircinata (Nyl.) H. Olivier = Aspicilia radiosa |
| Squamarina crassa (Huds.) Poelt = Squamarina cartilaginea |
| Squamarina crassa f. pseudocrassa (Mattick) Poelt = Squamarina cartilaginea |
| Squamarina crassa var. pseudocrassa (Mattick) D. Hawksw. = Squamarina cartilaginea |
| Staurothele catalepta = Staurothele fissa |
| Staurothele clopima = Staurothele areolata |
| Staurothele clopima = Staurothele fissa |
| Staurothele ebborensis Walt. Watson = Staurothele caesia |
| Staurothele innata Walt. Watson = Staurothele rugulosa |
| Staurothele umbrina (Wahlenb.) Tuck. = Staurothele fissa |
| Stegia vermicularis (Arnold) Keissl. = Thamnogalla crombei |
| Stenocybe bryophila Walt. Watson = Stenocybe nitida |
| Stenocybe byssacea (Fr.) = Stenocybe pullatula |
| Stenocybe euspora sensu Mudd = Stenocybe septata |
| Stenocybe major = Stenocybe septata |
| Stenocybe major var. macvicarensis Grélet = Stenocybe nitida |
| Stenocybe tremulicola Norrlin ex Nyl. = Phaeocalicium tremulicola (Norrlin ex Nyl.)
Tibell |
| Stenographa anguina europ. = Graphina anguina europ. |
| Stenographa anguina var. diffusa (Leight.) Mudd = Graphina anguina europ. |
| Stenographa anguina var. divaricata (Leight.) Mudd = Graphina anguina europ. |
| Stenographa anguina var. flexuosa (Leight.) Mudd = Graphina anguina europ. |
| Stenographa anguina var. pulverulenta sensu Mudd = Graphina anguina europ. |
| Stenographa anguina var. radiata (Leight.) Mudd = Graphina anguina europ. |
| Stenographa anomala (Leight.) Mudd = Graphina ruiziana |
| Stereocaulon botryosum Ach. = Stereocaulon cereolus = Pilophorus strumaticus |
| Stereocaulon condensatum subsp. cereolinum sensu Cromb. (1870) = Pilophorus
strumaticus |
| Stereocaulon coralloides Fr. = Stereocaulon dactylophyllum |
| Stereocaulon denudatum = Stereocaulon vesuvianum |
| Stereocaulon evolutoides (H. Magn.) Frey = Stereocaulon saxatile |
| Stereocaulon fastigiatum Anzi = Stereocaulon botryosum Ach. |
| Stereocaulon fastigiatum var. dissolutum H. Magn. = Stereocaulon spathuliferum |
| Stereocaulon incrustatum = Stereocaulon microscopicum (Vill.) Frey = Leprocaulon
microscopicum |
| Stereocaulon nanum (Ach.) Ach. = Leprocaulon microscopicum |
| Stereocaulon paschale (L.) Hoffm. = Stereocaulon paschale = Stereocaulon vesuvianum |
| Stereocaulon subcoralloides (Nyl.) Nyl. = Stereocaulon vesuvianum var. capitatum
(Flot. ex ) P. James = Stereocaulon vesuvianum var. nodulosum |
| Stereocaulon vesuvianum var. depressum (H. Magn.) I.M. Lamb = Stereocaulon vesuvianum
var. nodulosum |
| Stereocaulon vesuvianum var. pulvinatum = Stereocaulon vesuvianum var. vesuvianum |
| Sticta aurata Ach. = Pseudocyphellaria aurata |
| Sticta crocata (L.) Ach. = Pseudocyphellaria crocata |
| Sticta damicornis = Sticta canariensis |
| Sticta dufourii Delise = Sticta canariensis [blue-green phycotype] |
| Sticta glomulifera (Lightf.) Delise = Lobaria amplissima |
| Sticta herbacea (Huds.) Gray = Lobaria virens |
| Sticta intricata var. thouarsii (Delise) Nyl. = Pseudocyphellaria intricata |
| Sticta intricata var. thouarsii = Pseudocyphellaria norvegica |
| Sticta macrophylla sensu Borrer, non Bory ex Delise = Sticta canariensis [green
phycotype] |
| Sticta pulmonacea (Ach.) Ach. = Lobaria pulmonaria |
| Sticta pulmonaria (L.) Hook. = Lobaria pulmonaria |
| Sticta scrobiculata (Scop.) Ach. = Lobaria scrobiculata |
| Sticta sinuosa Pers. ex Gaudich. = Stictina crocata (L.) Nyl. = Pseudocyphellaria
crocata |
| Sticta sinuosa sensu Crundwell (1957) = Sticta canariensis [green phycotype] |
| Stictina dufourii (Delise) Nyl. = Sticta canariensis [blue-green phycotype] |
| Stictina fuliginosa (Hoffm.) Nyl. = Sticta fuliginosa |
| Stictina intricata var. thouarsii (Delise) Nyl. = Pseudocyphellaria intricata |
| Stictina intricata var. thouarsii = Pseudocyphellaria norvegica |
| Stictina limbata (Sm.) Nyl. = Sticta limbata |
| Stictina scrobiculata (Scop.) Nyl. = Lobaria scrobiculata |
| Stictina sylvatica (Huds.) Nyl. = Sticta sylvatica |
| Stigmatella circumscripta (Taylor) Mudd = Peterjamesia circumscripta |
| Stigmatidium circumscriptum f. dendrizum Nyl. = Peterjamesia circumscripta |
| Stigmatidium crassum (DC.) Duby = Enterographa crassa |
| Stigmatidium dendriticum Leight. = Arthonia atlantica |
| Stigmatidium hutchinsiae (Leight.) Nyl. = Enterographa hutchinsiae |
| Stigmatidium obscurum (Sm. & Sowerby) Spreng. = Enterographa crassa |
| Stigmatidium venosum = Enterographa crassa |
| Stigmatidium venosum = Enterographa elaborata |
| Stigmidium allogenum (Nyl.) D. Hawksw. = Arthopyrenia allogena |
| Stigmidium dispersum (J. Lahm ex ) D. Hawksw. = Zwackhiomyces dispersus |
| Stigmidium schaereri = Stigmidium congestum |
| Stigonema atrovirens (Dillwyn) C. Agardh = Ephebe lanata |
| Strangospora delitescens (Arnold) Coppins = Biatoridium delitescens |
| Strigula affinis (A. Massal.) R.C. Harris = incorrectly recorded from the British
Isles |
| Strigula affinis = Strigula jamesii |
| Strigula alpestris (Vzda) Hafellner = Strigula stigmatella var. alpestris |
| Strigula babingtonii Berk. = Dennisiella babingtonii (Berk.) Bat. & Cif. |
| Strigula diederichiana Etayo, Cl. Roux & Sérus. ad int. = Strigula phaea |
| Strigula lateralis Aptroot & Van den Boom = Strigula tagananae |
| Strigula stigmatella var. alpina (sphalm.) = Strigula stigmatella var. alpestris |
| Strongylium aciculare sensu Gray, non (Ach.) Gray = Chaenotheca hispidula |
| Strongylium capitellatum (Ach.) Gray = Chaenotheca furfuracea |
| Strongylium debile (Sm.) Gray = Chaenothecopsis debilis |
| Synalissa intricata (Arnold) Nyl. = Lempholemma intricatum |
| Synalissa kenmorensis Holl ex Nyl. = Porocyphus kenmorensis |
| Synalissa ramulosa (Hoffm.) = Synalissa symphoreav |
| Synaptospora tartaricola (Nyl.) Cain = Roselliniopsis tartaricola |
| Synechoblastus aggregatus = Collema fascicularev |
| Synechoblastus ascaridosporus (A. Massal.) Zahlbr. = Collema fasciculare |
| Synechoblastus complicatus (Schaer.) Mudd, non sensu Mudd = Collema cristatum |
| Synechoblastus complicatus sensu Mudd = Collema undulatum |
| Synechoblastus fascicularis (L.) A.L. Sm. = Collema fasciculare |
| Synechoblastus flaccidus (Ach.) = Collema flaccidum |
| Synechoblastus laureri = Collema undulatum |
| Synechoblastus multipartitus (Sm.) = Collema multipartitum |
| Synechoblastus nigrescens (Huds.) Trevis. = Collema nigrescens |
| Synechoblastus nigrescens = Collema furfuraceum |
| Synechoblastus polycarpus (Hoffm.) Dalla Torre & Sarnth. = Collema polycarpon |
| Synechoblastus rupestris (Sw.) Trevis. = Collema flaccidum |