- A`ala
- A’ala’ula
- Abrotanifolia
- Acanthobolus
- Acanthochondria
- Acanthochrysis
- Acanthocodium
- Achradina
- Aclistochara
- Acrochaetium
- Acrocladus
- Acrocystis
- Acrodiscus
- Acrosymphyton
- Acrothamnion
- Acrothamniopsis
- Acrotylus
- Actinococcus
- Actinodinium
- Actinoglena
- Actinothamnion
- Actinotrichia
- Actinozygus
- Acuturris
- Adamsiella
- Adelophycus
- Adelophyton
- Adenoides
- Adik goma
- Adik kalas
- Adnatosphaeridium
- Aeglophyllum
- Aeodes
- Aerosphaera
- Agar-agar haloes
- Agar-agar kasar
- Agar-agar koepan
- Agar-agar lesong
- Agar agar pulu
- Agar agar seru laut
- Agardhia
- Agardhiella
- Agardhinula
- Agar geser
- Agar gésér
- Agar poeloe
- Agar séran laoet
- Aglaophyllum
- Aglaothamnion
- Aglaozonia
- Agmenellum
- Ahmuellerella
- Ahnfeldtia
- Ahnfeltiopsis
- Ainu-wakame
- Aiolocolax
- Ajitsaki
- Akalaphycus
- Akase-iwanokawa
- Ake limu
- Aki-yore-moku
- Alatocladia
- Ala`ula
- Alcyonidium
- Alcyonium
- Aldorfia
- Alface-do-mar
- Alface miúda
- Alga perlada
- Algina
- Algirosphaera
- Algites
- Alisphaera
- Allogonium
- Allorgeia
- Alsidium
- Alternantia
- Alveosphaera
- Amanori
- Amansia
- Amaurolithus
- Amblyochara
- Amblyophis
- American dulse
- Amiculosphaera
- Amikusa
- Amithalithina
- Ammatoidea
- Ammodochium
- Amoenothamnion
- Amphiceratium
- Amphicocconeis
- Amphidiniopsis
- Amphidoma
- Amphiplexia
- Amphiroa
- Amphisbetema
- Amphisolenia
- Amphithrix
- Amphizygus
- Amphorochara
- Amphoropsis
- Amplisiphonia
- Amscottia
- Amylax
- Amyloodinium
- Amylophora
- Ana-amanori
- Ana-awosa
- Anabaenopsis
- Anacanthoica
- Anadarusu
- Anatheca
- Ancylonema
- Andalusiella
- Aneuria
- Aneurianna
- Anfractutofilum
- Animikiea
- Anisocladella
- Anisocladus
- Anisomonas
- Anisoschizus
- Ankistrodesmopsis
- Ankylonoton
- Annulina
- Anoplosolenia
- Anotrichium
- Antarctic kelp
- Antarcticophyllum
- Antarcticothamnion
- Antarctocolax
- Anthosphaera
- Anticomonas
- Antithamnion
- Antithamnionella
- Antrocentrum
- Antrosphaera
- Ao-kombu
- Ao-obakusa
- Aosa
- Ao-wakame
- Apatococcus
- Aphanocapsaopsis
- Aphanocladia
- Aphanta
- Apiochloris
- Apiocystis
- Apodococcus
- Apoglossocolax
- Apoglossum
- Apona
- Apophlaea
- Appeninocodium
- Aprobolocysta
- Aptea
- Apteodinium
- Arachnophyllum
- Ar-arucep
- Ararucip
- Archaeofavosina
- Archaeolithothamnion
- Archaeolithothamnium
- Archaeperidinium
- Ardissonea
- Ardissonula
- Ardreanema
- Areschougia
- Argillamonas
- Aristella
- Aristoptilon
- Aristothamnion
- Arkhangelskiella
- Arthopyrenia
- Arthronema
- Arturoa
- Asakusa nori
- Asakusa-nori
- Asame
- Ascocladium
- Ascoglena
- Ascophylla
- Ascothamnion
- A’shab bahriya
- Aspalatia
- Asperocaulon
- Asperococcus
- Asphaltinella
- Aspidophora
- Asterocapsa
- Asterochloris
- Asterocolax
- Asterocytis
- Asterodinium
- Asteromenia
- Astrocladium
- Asymetrica
- Asymmetria
- Atelodinium
- Athenagalea
- Atlanticellodinium
- Atlantic kombu
- Atlantodinium
- Atomaria
- Atractella
- Atraktomonas
- Atsuba-nori
- Atsukawa-hitoe
- Augophyllum
- Aulacomonas
- Aulosira
- Aureodinium
- Australisphaera
- Austroclonium
- Austrophyllis
- Avellodinium
- Awo-nori
- Awosa
- Axilosphaera
- Axopodorhabdus
- Axosiphon
- Bacchidinium
- Baccy juice
- Bacillosiphon
- Bacinellacodium
- Bactrophora
- Badderlocks
- Bagão
- Baillouviana
- Bakothamnion
- Balaniger
- Balanosa
- Balanus-hildenbrandia-mucosa
- Baldinia
- Baldockia
- Balechina
- Balliella
- Balliopsis
- Baltic agar
- Balticola
- Baltisphaeridium
- Bamboo seaweed
- Bangia
- Bangiella
- Bangiomorpha
- Baradlaia
- Barner kombu
- Barraí raice
- Barrchonlach
- Bartoniella
- Batiacasphaera
- Batioladinium
- Batrachospermella
- Batrachospermum
- Battersia
- Baylesia
- Bebiroe
- Bebojot
- Beckerella
- Beckia
- Beerentang
- Bejin gwenn
- Benifukuronori
- Beni-mayudama
- Beni-ogonori
- Beni-tasa
- Benzaitenia
- Bernardinella
- Bernardinium
- Bevocastria
- Bicarinellum
- Biceratium
- Bicolumnus
- Bicornis
- Bicosta
- Bicuspidellopsis
- Bidiscus
- Big green algae
- Bilgramia
- Bindera
- Binderella
- Binder’s sargassum weed
- Binghamiella
- Binuclearia
- Bipedinomonas
- Birnentang
- Birodo-kombu
- Bisbullatum
- Biturricula
- Black carrageen
- Black kelp
- Black kombu
- Black-kombu
- Black wrack
- Bladder kelp
- Blanket weed
- Blasentang
- Blastodinium
- Blepharocysta
- Blidingia/algaebase
- Blinksia
- BlÔm
- Blossevillea
- Blue weeds
- Blutroter seeampfer
- Boa kelp
- Bodelha
- Bodomonas
- Boeloeng
- Boelong
- Boergeseniella
- Boghead coals
- Bolboclinium
- Boldia
- Boletuvelum
- Bolgach
- Bolgán
- Bonnemaisonia
- Bootlace weed
- Boreadinium
- Boreolithon
- Boreothamnion
- Borrichius
- Boryna
- Borzinema
- Bossea
- Botelha
- Botelhas
- Botelho-comprido
- Botryella
- Botryocarpa
- Botryochrysis
- Botryocladia
- Botryoglossum
- Botryokoryne
- Botryosphaera
- Botryosphaerella
- Boueina
- Bourellyodesmus
- Bowiesia
- Braarudosphaera
- Bracebridgea
- Brachidinium
- Brachionococcus
- Brachycladia
- Brachynema
- Brachytheca
- Brachythrix
- Brachytrichiopsis
- Branchioglossum
- Branchiophilus
- Brasilonema
- Brassierea
- Brick-arame
- British agar
- Broadleaf kelp
- Broadleaf seagrass
- Brochidium
- Broinsonia
- Brown kelp
- Bryobesia
- Bryocladia
- Bryothamnion
- Bulbotrichia
- Bull kelp
- Bull whip kelp
- Bullwhip kelp
- Burkillia
- Burmese moss
- Bushy ahnfelt's seaweed
- Butschliella
- Button weed
- Bysmatrum
- Cabelo-de-velha
- Cabhthaí
- Cachonina
- Cachonodinium
- Cagniardia
- Caisíneach
- Cáithleach
- Calciarcus
- Calciodinellum
- Calciopappus
- Calciosolenia
- Calicasphaera
- Calidictyon
- California laver
- Caligodinium
- Calliacantha
- Calliarthron/algaebase
- Calliblepharis
- Calliclavula
- Callidictyon
- Callithamniella
- Callithamnion
- Callocolax
- Callophycus
- Callophyllis
- Calloseris
- Calocladia
- Calocylindrus
- Caloglossa
- Calomena
- Calonitophyllum
- Calosiphonia
- Calycimonas
- Calyptrolithina
- Calyptrolithophora
- Calyptrosphaera
- Camontagnea
- Camptothrix
- Camptylonema
- Camptylonemopsis
- Campylaephora
- Caneosphaera
- Canistrocarpus
- Canistrolithus
- Canningia
- Cannosphaeropsis
- Caocaoyan
- Capea
- Capillicysta
- Capraella
- Capreolia
- Capsicarpella
- Capsosira
- Cardiomonas
- Carduifolia
- Carminella
- Carpacanthus
- Carpathocodium
- Carpoblepharis
- Carpococcus
- Carpodesmia
- Carpopeltis
- Carpothamnion
- Carradoria
- Carraghean
- Carragheen moss
- Carraigín
- Carraigín fiadháin
- Casfheamainn
- Casóg
- Cassiculosphaeridia
- Catella
- Catenella
- Catenellocolax
- Catenellopsis
- Catenochrysis
- Catenococcus
- Catenocystis
- Cattle sargassum weed
- Caulacanthus
- Caulinia
- Caulodendron
- Cayeuxia
- Ceanna slat
- Ceann a' tslat
- Cecidochloris
- Cenacrum
- Centosphaera
- Centrasphaeridium
- Centroceras
- Centrocerocolax
- Centrodinium
- Ceonogonium
- Cephalocystis
- Cephalomonas
- Ceramianthemum
- Ceramicola
- Ceramiella
- Ceramothamnion
- Ceratocolax
- Ceratocorys
- Ceratodictyon
- Ceratodinium
- Ceratoperidinium
- Ceylon moss
- Chabo-obakusa
- Chadefaudiothrix
- Chaetangium
- Chaetobolus
- Chaetoceras
- Chaetocladiella
- Chaetolithon
- Chaetomorphopsis
- Chaetonella
- Chaetotheke
- Chain bladder
- Chai tai
- Cha-kombu
- Chalubinskia
- Chamaecalyx
- Chamaenema
- Chamaesiphonopsis
- Chamaethamnion
- Champia
- Champiocolax
- Channel wrack
- Chantransia
- Charlesdowniea
- Chascon
- Chauvinia
- Cheilosporum
- Chevaliericrusta
- Chiao tsai
- Chiasmolithus
- Chiastozygus
- Chiau tsai
- Chi choy
- Chicory sea lettuce
- Chigaiso
- Chiharaea
- Chihsienella
- Chijimi-kombu
- Chilin-t' sai
- Chinese moss
- Chiracanthia
- Chishima-gohai-kombu
- Chishima kuro-nori
- Chishima-kuronori
- Chishima-nekoashi-kombu
- Chishima-wakame
- Chi tsai
- Chlamydobotrys
- Chlamydomonadopsis
- Chlamydonephris
- Chlamydophorella
- Chlidophyllon
- Chlorallanthus
- Chlorangiella
- Chlorangiopsis
- Chlorangium
- Chloranomala
- Chlorcorona
- Chlorellopsis
- Chloremys
- Chlorepithema
- Chlorobrachis
- Chloroceras
- Chlorochromonas
- Chlorochytridion
- Chloroclados
- Chlorocystis
- Chlorodendron
- Chlorogloeaopsis
- Chlorogloeopsis
- Chloroidium
- Chlorojackia
- Chlorolobion
- Chloronephris
- Chloronitum
- Chloronomala
- Chlorophaeoclonium
- Chlorophysema
- Chloroplana
- Chloroplegma
- Chloropteridella
- Chlorosiphon
- Chlorotetras
- Chodatellopsis
- Chondracanthus
- Chondria
- Chondriella
- Chondriopsis
- Chondroclonium
- Chondrococcus
- Chondrocystis
- Chondrodictyon
- Chondrogloea
- Chondrophycus
- Chondrosiphon
- Chondrosphaera
- Chondrothamnion
- Chondrymenia
- Chonemonas
- Chonggak
- Chorão
- Chorão do mar
- Choreocolax
- Choreonema
- Chroa
- Chromastrum
- Chromopeltis
- Chromulinella
- Chroococcidium
- Chroococcopsis
- Chroodactylon
- Chrooderma
- Chroogloeocystis
- Chroothece
- Chrysastridium
- Chrysobotrys
- Chrysocampanula
- Chrysochaete
- Chrysococcocystis
- Chrysoculter
- Chrysodictyon
- Chrysoglena
- Chrysoiklos
- Chrysomeris
- Chrysomonas
- Chrysomoron
- Chrysothallus
- Chrysotheca
- Chrysothrix
- Chrysotylos
- Chrysowaernella
- Chrysymenia
- Chylocladia
- Chytraphora
- Chytriodinium
- Ciliaria
- Circulodinium
- Cirrulicarpus
- Citharistes
- Clabhthaí
- Cladhymenia
- Cladodonta
- Cladogirvanella
- Cladogonium
- Cladophorella
- Cladopyxis
- Cladurus
- Claidhmh
- Claíomh
- Clarionea
- Clathrocystis
- Clathromorphum
- Claudea
- Clautriavia
- Clavatella
- Claviclonium
- Cleistosphaeridium
- Cliftonaea
- Cliftonia
- Clipeodinium
- Closteriospira
- Cloudy kombu
- Cluaisíní
- Clúimhín cait
- Coccidinium
- Coccochloris
- Coccocladus
- Coccolithites
- Coccomonas
- Coccopedia
- Coccotylus
- Cochajugo
- Cochayugo
- Cochlodinium
- Cochlosoma
- Codiophyllum
- Codomonas
- Codoniella
- Codonomonas
- Coelarthrum
- Coeloclonium
- Coelocystis
- Coelodictyon
- Coelomoron
- Coeloseira
- Coelosphaeriopsis
- Coelosphaerium
- Coelothrix
- Coenochloris
- Coenococcus
- Coenogonium
- Coenolamellus
- Coirleach
- Coirrleach
- Colacium
- Colacodasya
- Colacodictyon
- Colacolepis
- Colaconema
- Colacopsis
- Coleodesmiopsis
- Colliculoamphora
- Collinella
- Collinsiellopsis
- Color changer
- Colteronema
- Comasphaeridium
- Common porphyra
- Compsopogon
- Compsothamnion
- Compsothamnionella
- Condrus
- Conferva
- Congracilaria
- Congregatocarpus
- Congruentidium
- Conjugata
- Conochaete
- Conophyton
- Conradia
- Contarinia
- Coolia
- Corallophila
- Corallopsis
- Coral moss
- Corbisema
- Cordas
- Cordosphaeridium
- Cordylecladia
- Coriophyllum
- Corisphaera
- Cornicularia
- Corninho
- Corollithion
- Coronastrum
- Coronia
- Coronodiscus
- Coronopifolia
- Coronosphaera
- Corradoria
- Correas
- Corriolas
- Corsican moss
- Corymbellus
- Corynephora
- Corynocystis
- Corynomorpha
- Corynospora
- Coryphidium
- Corythodinium
- Cosáinín carraige
- Cosmaridium
- Cosmiodiscus
- Cosmoastrum
- Costatochloris
- Costularia
- Cottoniella
- Cottonii
- Cow's tail
- Cow tang
- Coyofe
- Crannogh
- Crannough
- Craonach
- Craspedocarpus
- Craspedolithus
- Craspedopleura
- Craspedoporus
- Craspedotella
- Crassapontosphaera
- Crassicorbisema
- Crassikamaena
- Crassitegula
- Craterospermum
- Creannach
- Creanna garbh
- Creathnach
- Crenalithus
- Cretan sea plant
- Cretarhabdella
- Cretarhabdus
- Cribrokamaena
- Cribroperidinium
- Cribrosphaera
- Cribrosphaerella
- Cricolithus
- Crinalium
- Crinolina
- Croatella
- Croftiella
- Crop of threads
- Crossocarpus
- Crossophialus
- Crouania
- Crouaniella
- Crouaniopsis
- Crouanophycus
- Crúba préacháin
- Crucidenticula
- Crucigloea
- Cruciplacolithus
- Crude agar
- Cruibín chait
- Cruoriella
- Cruoriopsis
- Cryptarachne
- Crypthecodinium
- Cryptobia
- Cryptococcolithus
- Cryptoglena
- Cryptonemia
- Cryptoperidiniopsis
- Cryptopleura
- Cryptosiphonia
- Crystallolithus
- Ctenosiphonia
- Cubiculosporum
- Cumagloia
- Cumathamnion
- Cúnach triosgar
- Cuneatochara
- Cupóg na gcloch
- Curdiea
- Curly gristle moss
- Curly moss
- Cuspelho
- Cuspidothrix
- Cussia
- Cut kombu
- Cutted-kombu
- Cuvie
- Cyanarcus
- Cyanoarbor
- Cyanobium
- Cyanocatena
- Cyanocatenula
- Cyanocomperia
- Cyanocystis
- Cyanoderma
- Cyanodermatium
- Cyanodictyon
- Cyanogastrum
- Cyanogranis
- Cyanokybus
- Cyanonephron
- Cyanophanon
- Cyanophora
- Cyanoptyche
- Cyanosarcina
- Cyanospira
- Cyanostylon
- Cyanotetras
- Cyanothamnos
- Cyanothece
- Cyanothrix
- Cyathochrysis
- Cyclicargolithus
- Cyclidium
- Cyclonephelium
- Cycloperfolithus
- Cyclotrichium
- Cyclotubicoalitus
- Cylindralithus
- Cylindrocapsopsis
- Cylindrospermopsis
- Cylindrospira
- Cymatiogalea
- Cymatiosphaera
- Cymbodinium
- Cymbopleura
- Cymbosira
- Cymososphaeridium
- Cypellachaetes
- Cyrtosphaera
- Cyrtymenia
- Cystoclonium
- Cystodictyon
- Cystodinedria
- Cystodinium
- Cystophyllum
- Cystopleura
- Dactylofusa
- Dactylymenia
- Daktylethra
- Dalmatella
- Danish agar
- Darusu
- Dashi kombu
- Dashi-kombu
- Dasycladus
- Dasyclonium
- Dasyella
- Dasyopsis
- Dasyphila
- Dasyphloea
- Dasyphylla
- Dasyptilon
- Dasysiphonia
- Dasythamnion
- Dateriocradus
- Dawsoniocolax
- Dead men's ropes
- Debarya
- Decaisnella
- Deflandrea
- Delesseriopsis
- Delisea
- Denticella
- Denticulopsis
- Dermatolithon
- Dermocarpella
- Dermocorynus
- Dermonema
- Desikacharyella
- Desmia
- Desmocapsa
- Desmomastix
- Desmosiphon
- Desmotetra
- Deutschlandia
- Devaleraea
- Diademoides
- Diadenus
- Diadozygus
- Diaphanoeca
- Diapse
- Diaster
- Dichloria
- Dichonema
- Dichophycus
- Dichothrix
- Dichotomaria
- Dickensoniaforma
- Dicoleon
- Diconodinium
- Dicranema
- Dicroerisma
- Dicroglossum
- Dictyastrum
- Dictyerpa
- Dictyochlorella
- Dictyochroa
- Dictyococcites
- Dictyococcus
- Dictyomenia
- Dictyophora
- Dictyopyxidia
- Dictyopyxis
- Dictyosphaeriopsis
- Dictyothamnion
- Dictyotidium
- Dicurella
- Didymocladon
- Didymonema
- Didymoprium
- Didymothrix
- Diexallophasis
- Digeneopsis
- Dihe
- Dillesk
- Dillisc
- Dillisk
- Dilophus
- Dilsea
- Dimastigamoeba
- Dinamoebidium
- Dinastridium
- Dinematomonas
- Dinobryopsis
- Dinoclonium
- Dinococcus
- Dinofurcula
- Dinogymnium
- Dinopodiella
- Dinoporella
- Dinopyxis
- Dinosphaera
- Dinothrix
- Dioriticamonas
- Diplochaete
- Diplochloris
- Diplocolon
- Diplocystis
- Diploderma
- Diplodinium
- Diplopelta
- Diplopeltopsis
- Diplopsalis
- Diplopsalopsis
- Diplostromium
- Diplothamnion
- Diporidion
- Dipterosiphonia
- Discocytis
- Discodinium
- Discolithina
- Discolithus
- Discoplastis
- Discosphaera
- Discostella
- Dissodinium
- Dissodium
- Distigma
- Distigmopsis
- Ditria
- Diversocallis
- Djadja
- Djamu batu
- Djanggoet
- Docidium
- Dock-leaved delesseria
- Doejoeng
- Dogelodinium
- Dohrniella
- Doidyx
- Dolichoscelis
- Doliocatella
- Domatomonas
- Domoi
- Donezella
- Dorakusa
- Dorset weed
- Doruithe briain
- Dotyophycus
- Doxodasya
- Drewiana
- Dried dulse
- Dried moss
- Driftweed
- Drilosiphon
- Drouetia
- Druggidium
- Dry limu
- Dubhlamán
- Duboscquodinium
- Dudresnaya
- Duilleasg
- Duillisg
- Dulsan
- Dumontia
- Durinskia
- Dyers fucus
- Dysphinctium
- Dzensia
- East-indian carrageen
- Ebisume
- Ebriopsis
- Ecballocystis
- Ecdysichlamys
- Echinocaulon
- Echinoceras
- Echinochrysis
- Echinocoleum
- Echinophycus
- Echinosphaerella
- Echinosporangium
- Echinothamnion
- Echter seequirl
- Ectochaete
- Ectoclinium
- Ectogeron
- Ectophora
- Edible kelp
- Egmontodinium
- Ego nori
- Egonori
- Ehrenbergiulva
- Eisenackidium
- Elachistiella
- Eleutheropyxis
- Eleutherospora
- Elk kelp
- Ellipsagelosphaera
- Ellipsoidictyum
- Ellipsolithus
- Ellipsoplacolithus
- Ellisius
- Embryocola
- Empselium
- Enaga-kombu
- Enaga-onikombu
- Enaga-wakame
- Enantiocladia
- Enchelis
- Encoelium
- Encyonopsis
- Endocladia
- Endodictyon
- Endodinium
- Endogenes
- Endonema
- Endoscrinium
- Endosiphonia
- Endosperma
- Endotrichia
- Enelittosiphonia
- Ensiculifera
- Enteronia
- Entocladia
- Entoderma
- Entodictyon
- Entomosigma
- Entophysalis
- Entosiphon
- Entosphaeroides
- Entothrix
- Eoplectonema
- Epicladia
- Epigloeosphaera
- Epiglossum
- Epilithia
- Epilithon
- Epimastopora
- Epineuron
- Epiperidinium
- Epiphloea
- Episperma
- Episporium
- Epulo
- Epymenia
- Ercegovicia
- Ericiolus
- Ericsonia
- Ernstiella
- Errerella
- Erythrocladia
- Erythrocladus
- Erythroclathrus
- Erythroclonium
- Erythrocolon
- Erythrocystis
- Erythrodermis
- Erythroglossum
- Erythronaema
- Erythropeltis
- Erythrophyllum
- Erythropsidinium
- Erythropsis
- Erythrotrichia
- Erythrotrichopeltis
- Erythrymenia
- Escad
- Escharisphaeridia
- Esgalhota
- Esoptrodinium
- Estalos
- Estiastra
- Ethelia
- Ethmorhabdus
- Ettliella
- Euastropsis
- Eucapsis
- Eucheuma
- Eucheuman
- Euctenodus
- Euglenamorpha
- Euglenomonas
- Euglenopsis
- Euhymenia
- Euphyllodium
- Eupogodon
- Eupogonium
- Eupoikilofusa
- Euptilocladia
- Euptilota
- Eurhabdus
- Eurydinium
- Euspiros
- Eutetramorus
- Euthora
- Eutreptia
- Eutreptiella
- Euzonia
- Euzoniella
- Excentrosphaera
- Exilicrusta
- Exochosphaeridium
- Exophyllum
- Exuviaella
- Ezo-tsunomata
- Ezo-wakame
- Fah tsai
- Fah tsoi
- Fairies butter
- Falkenbergiella
- Falklandiella
- Farlowia
- Farlowiella
- Fastigaria
- Fastigiaria
- Fat tsai
- Faucheocolax
- Faucheopsis
- Feam
- Feamainn bhoilgíneach
- Feamainn bhuí
- Feamainn bhuidhe bhoilgíneach
- Feamainn mhuirgha
- Feamnach bhuí
- Feamnach dhubh
- Feamuinn bharr chladaigh
- Feamuinn bhuilgíneach
- Feamuinn dearg
- Feather boa kelp
- Feather-boa kelp
- Feditia
- Feldmannodora
- Feldmannophycus
- Felsenmoos
- Fen tsai
- Fernandinella
- Fernandosiphonia
- Fibrocysta
- Fil de fur
- Filisphaera
- Filodinium
- Filoprotococcus
- Fimbriaria
- Fimbrifolium
- Fingered tangle
- Fingertang
- Fingertare
- Fir needle
- Fischera
- Fischerella
- Fischerellopsis
- Fitas
- Flabellochara
- Flahaultia
- Flat wrack
- Flosculosphaera
- Fluitomonas
- Fluted nori
- Folha-de-alface
- Folha-de-carriola
- Folhinha
- Folhuda
- Foliactiniscus
- Forest kelp
- Forma minor
- Forma tenuoir
- Fortiea
- Fosliella
- Fottea
- Fotterella
- Fouet de sorcier
- Fragilidium
- Franceia
- Fraoch freangach
- Fremyella
- Friedaea
- Frikkiella
- Fromea
- Fruill
- Fryeella
- Fucodium
- Fucus crispus
- Fucus vésiculeux
- Fukoro-funori
- Fukuro-funori
- Fukuronori
- Funicularius
- Funoran
- Funori
- Funorin
- Furcellaran
- Furcellaria
- Furcilla
- Furgin
- Fusa-iwazuta
- Fuscaria
- Futo-mozuku
- Futo-uikyômo
- Gaarderia
- Gaggara-kombu
- Gagome
- Gaillardotella
- Gaillona
- Gaillonella
- Gainia
- Galaxaura
- Galeidinium
- Galhdr-ka-palta
- Gambierdiscus
- Gamgamet
- Ganonema
- Gardneriella
- Gardnerula
- Gardodinium
- Gartnerago
- Garwoodia
- Gastrophycus
- Gattya
- Gayliella
- Geitleria
- Geitleribactron
- Geitleriella
- Geitlerinema
- Gelatia
- Gelatintang
- Gelídeos
- Gelidiocolax
- Gelidiopsis
- Gelinaria
- Gemeine gabelzunge
- Gemeine meersaite
- Gemeiner geisseltang
- Gemeiner horntang
- Gemellicystis
- Gemmichara
- Gemmiphora
- Geniculus
- Geochrysis
- Geonettia
- Georgiella
- Gessnerium
- Ghoshia
- Giant bladder kelp
- Giant bull kelp
- Giant pacific kelp
- Giant perennial kelp
- Gibsmithia
- Gigantochloris
- Gigartina
- Gimberi
- Gimberi-kombu
- Ginbaso
- Ginnania
- Ginnanso
- GinnansÔ
- Gladiolithus
- Glandothamnus
- Glaphyrocysta
- Glaphyrymenia
- Glasán
- Glaucocystopsis
- Glaucosphaera
- Glaucospira
- Glenobotrydion
- Glenodinium
- Globulaesphaeridium
- Glochiococcus
- Gloeoactinium
- Gloeocapsopsis
- Gloeochaete
- Gloeochlamys
- Gloeocystopsis
- Gloeomonas
- Gloeophycus
- Gloeoplax
- Gloeotaenium
- Gloeotrichia
- Gloiocladia
- Gloiocolax
- Gloioderma
- Gloiodictyon
- Gloiohymenia
- Gloiophloea
- Gloiophyllis
- Gloiosaccion
- Gloiosiphonia
- Gloiotrichia
- Gloiotrichus
- Glossophorella
- Glyphodinium
- Goat tang
- Gobei-kombu
- Gobichara
- Gochteodinia
- Gochtodinium
- Godlewskia
- Goéman à vache
- Goémon à vaches (dulse)
- Goemon blanc
- Gomontiella
- Gomphosphaeria
- Gonatoblaste
- Gonatogenia
- Gonatonema
- Gondisphaeridium
- Gongolaria
- Gonidium
- Gonimocolax
- Gonimophyllum
- Goniolithon
- Goniosphaeridium
- Goniotrichopsis
- Goniotrichum
- Gonokenori
- Gonyaulacysta
- Gordoniella
- Gorgonisphaeridium
- Gotoius
- Goumaocai
- Gracilariophila
- Gracilariopsis
- Graesiella
- Grallatoria
- Grambastichara
- Grammephora
- Grammitella
- Granomarginata
- Grantarhabdus
- Granulocystis
- Granulocystopsis
- Granuochloris
- Grapestone
- Grateloupiocolax
- Grayemma
- Great bullwrack
- Great kelp
- Green kombu
- Green sea-velvet
- Greuetodinium
- Griabhán
- Griffithsia
- Grinnellia
- Grisetang
- Gristle moss
- Griuán
- Grovesichara
- Guiryella
- Gulaman dagat
- Gulaman-dagat
- Gulf weed
- Gulsonia
- Gunflintia
- Guraman
- Gymnaster
- Gymnocystodinium
- Gymnogongrus
- Gymnophlaea
- Gymnophycus
- Gymnothamnion
- Gymnozyga
- Gynogonadinium
- Gyrodinium
- Gyrogona
- Gyropaigne
- Hababiro-kombu
- Haba-damashi
- Habano-himo
- Habonori
- Haematocelis
- Haematophloea
- Haematostagon
- Haemescharia
- Hae tae
- Hafgygia
- Hafniasphaera
- Hai-cai
- Haidadinium
- Hai dai
- Hai-houan
- Haiiro-shiwogusa
- Hailo
- Hai mien san
- Hair-shaped green algae
- Haisai kun-po
- Hai tai
- Hai-tai
- Hai-ten-gusa
- Hai-tengusa
- Hai ti tun
- Hai toe din
- Hai tsai
- Hai tsao
- Hai tso
- Hake-kashirazaki
- Halarachnion
- Halichrysis
- Halicnide
- Halicystis
- Haliptilon
- Halochlorella
- Halomicronema
- Halopappus
- Halophilodinium
- Halopithys
- Haloplegma
- Halosacciocolax
- Halosaccion
- Halosia
- Halostylodinium
- Halothamnion
- Halurus
- Halydictyon
- Halysium
- Hana-funori
- Hanaori
- Hanayana
- Hanayanagi
- Hane-kurogashira
- Hanovia
- Hanowia
- Hansgirgia
- Hapalosiphon
- Haplocladium
- Haplodasya
- Haplodinium
- Haplozoon
- Hapsocysta
- Hapterophycus
- Haraldia
- Harigane
- Harpoon weed
- Harrisichara
- Harveyella
- Hassallia
- Hayaster
- Hay tsay
- Heaven vegetable
- Hediniella
- Hedstroemia
- Helgolandinium
- Heliaktis
- Helicopedinella
- Helicopontosphaera
- Helicosphaera
- Helicothamnion
- Heliolithus
- Heliorthus
- Helladosphaera
- Helminthiopsis
- Helminthochorton
- Helminthocladia
- Helminthora
- Helmyton
- Hemichloris
- Hemicystodinium
- Hemineura
- Hemitoma
- Hemitrema
- Hennedya
- Henware
- Heribaudiella
- Heringia
- Hermesinella
- Hermesinum
- Herpochaeta
- Herpochondria
- Herpophyllon
- Herpopteros
- Herposiphonia
- Herpothamnion
- Herpyzonema
- Heteraulacus
- Heterobractum
- Heterochordaria
- Heterochromonas
- Heterochromulina
- Heterocladia
- Heterocyanococcus
- Heterocystis
- Heterodasya
- Heteroderma
- Heterodinium
- Heterodoxia
- Heteroglossum
- Heterohormogonium
- Heteronema
- Heteroptilon
- Heterorhabdus
- Heteroschisma
- Heterosiphonia
- Heterosphondylium
- Heterostroma
- Heterothamnion
- Heterothrichopsis
- Heterothrix
- Hibamata
- Hibatsunomata
- Hida-hitoe
- Hideophyllum
- Hiemalomonas
- Hildenbrandia
- Himandactylius
- Himantidium
- Hime-kayamo
- Hime-kombu
- Hime-murasaki
- Hime-nebarimo
- Hime-obakusa
- Hime tengusa
- Himo-nagamatsumo
- Hinanori
- Hindakochloris
- Hira-kotiji
- Hirakusa
- Histiophysis
- Hitoegusa
- Höckertang
- Hofmania
- Hoiro-kombu
- Hoi tsoi
- Hoi tsou
- Hokkai-moku
- Hollenbergia
- Holly limu
- Holmesia
- Holmsella
- Holococcolithophora
- Holopedium
- Holotrichia
- Hommersandia
- Hommersandiella
- Homoeoptyche
- Homozygosphaera
- Hondawara
- Honey ware
- Honeyware
- Hormathonema
- Hormidiella
- Hormidiopsis
- Hormidiospora
- Hormoceras
- Hormophora
- Hormoscilla
- Hormospora
- Hormothece
- Hormotrichum
- Horned wrack
- Hornibrookina
- Hornichara
- Horsetail kelp
- Horsetail tangle
- Hortobagyiella
- Hosame-kombu
- Hoshi-nori
- Hoshinori
- Hoso-hibimidoro
- Hoso kabanori
- Hoso-kagimotsuregusa
- Hosokenomimi
- Hosome-kombu
- Hoso-yezobukuro
- Huilte
- Hummbrella
- Hummertang
- Hung tsai
- Hung tsoi
- Hunsai
- Husseya
- Husseyella
- Huttoniella
- Hyaliella
- Hyalobrachion
- Hyalocardium
- Hyalochlorella
- Hyalogonium
- Hyalopoda
- Hyaloraphidium
- Hydraea
- Hydrococcus
- Hydrocoleum
- Hydrocoryne
- Hydrolapatha
- Hydrolithon
- Hydropuntia
- Hydrosolen
- Hyella
- Hymenena
- Hymenocladia
- Hymenocladiopsis
- Hymenoclonium
- Hypheothrix
- Hyphomorpha
- Hypnean
- Hypneocolax
- Hypnophycus
- Hypoglossum
- Hypophyllum
- Hystrichodinium
- Hystrichokolpoma
- Hystrichosphaera
- Hystrichosphaeridium
- Hystrichosphaeropsis
- Hystrichostrogylon
- Ichimatsu-nori
- Ichthyocercus
- Ichthyodinium
- Ichthyodontum
- Iers mos
- Igisu
- Igusu
- Ihekas atlebal
- Ihekesten
- Ihixlhewis
- Imantonia
- Imbatodinium
- Imleacán cloch
- Imose-miru
- Impagidinium
- Impluviculus
- Inactis
- Indodinium
- Indonesian irish moss
- Indosphaera
- Ineffigiata
- Inomeria
- Interfilum
- Interthamnion
- Intip-intip
- Invertocysta
- Involucrana
- Iridaea
- Iridea
- Irisches moos
- Irischmoos
- Irländisches moos
- Irtugovia
- Irvinea
- Isabelidinium
- Isabottia
- Ishi-mozuku
- Isingglass
- Islandinium
- Isocystis
- Isogawara
- Iso-hanabi
- Iso-iwatake
- Isophlis
- Isymenia
- Itanigusa
- Itanigusa saimi
- Ito-kayamo
- Ito-wakame
- Iwagesho
- Iwa-nori
- Iwanori
- Iyengariella
- Iyengariomonas
- Izziella
- Jaagia
- Jaagichlorella
- Jaaginema
- Jade nori
- Jadwigia
- Jafna moss
- Janczewskia
- Janetosphaera
- Jantinella
- Jaosaccion
- Japanese moss
- Japan sargassum
- Japansche scheleiachtige mos
- Java agar
- Jeannerettia
- Jelly bags
- Jelly moss
- Joculator
- Johnsonicodium
- Jomonlithus
- Juranyiella
- Kaau tsoi
- Kab kab
- Kabonori
- Kagikenori
- Kaijinso
- Kai-wan
- Kajime
- Kajimi
- Kakabekia
- Kala-lauli`i
- Kala-launui
- Kallonema
- Kallosphaeridium
- Kallymenia
- Kallymeniopsis
- Kalyptea
- Kammtang
- Kan-hoa
- Kansodinium
- Kanten weed
- Kappaphycus
- Karafuto-kanten
- Karafuto kombu
- Karafuto-kombu
- Karafuto-marimo
- Karafuto-mozuku
- Karafuto tororo kombu
- Karafuto-tororo-kombu
- Karafuto-wakame
- Karegna
- Karragener
- Katagnymene
- Kata-nori
- Kata-obakusa
- Katemen-kirinsai
- Katodinium
- Kauat-kauat
- Kawanori
- Kayamonori
- Keikansai
- Kelp flag
- Kelp meal
- Kelp ware
- Kenashi-shiwomidoro
- Kentrosiga
- Kentrosphaera
- Kephyriopsis
- Keppenodinium
- Keratococcus
- Keriochlamys
- Ke-sien-mi
- Ke-urushigusa
- Kildinella
- Kimberi
- Kimberi-kombu
- Kintarosiphonia
- Kintokiocolax
- Kinukusa
- Kinu-shiwogusa
- Kirchneria
- Kirchneriellosaccus
- Kirinsai
- Kiru-miru
- Kisselovia
- Kito-hitoegusa
- Kizami-kombu
- Kizami-wakami
- Kjellmania
- Klebsormidium
- Kleithriasphaeridium
- Klop-tsai-yup
- Knobbed wrack
- Knorpeltang
- Knotentang
- Knuppetang
- Kobayasiella
- Kofoidinium
- Kohu
- Kohu koko
- Kohu lipeche
- Kohu lipehe
- Koiro-kombu
- Kolkwitziella
- Komarekia
- Kome-nori
- Komvophoron
- Korean nori
- Korschpalmella
- Kosuji-nori
- Koteshio
- Kotoji-tsunomata
- Kotojitsunomata
- Kotsubu-nebarimo
- Kouanpon
- Koxianmi
- Kraftia
- Krkia
- Krybolopteris
- Kryptoperidinium
- Kuetzingia
- Kumade-kombu
- Kumado-kombu
- Kunashiri-wakame
- Kunpu
- Kurogia
- Kuroha-ginnanso
- Kuro-hitoegusa
- Kuro-kombu
- Kuro-nori
- Kuro-tororo kombu
- Kusa-mozuku
- Kuschutschitsch
- Kutare
- Kuvashi-kombu
- Kvaleya
- Kwanpo
- Kwanpu
- Kyauk pewint
- Kylindrocysta
- Kylinia
- Kyrtuthrix
- Lacrymasphaera
- Lacrymorphus
- Lacy sea lettuce
- Lady wrack
- Lagenella
- Lagenula
- Láin
- Laingia
- Láir
- Láir bhán
- Laitue de mer
- Laitue rouge
- Laminaire sucrée
- Laminolithus
- Lamourouxia
- Lamprothamnium
- Lamprothamnus
- Landlady's wig
- Lanternosphaeridium
- Lapideacassis
- Láracha
- Lásaí fruill
- Lasiothalia
- Latifascia
- Latochara
- Laurenciophila
- Lauterbornia
- Laver-bread
- Laver slack
- Laver sloke
- Leaba phortáin
- Leaba portáin
- Leachiella
- Leathach
- Leathach dearg
- Leather tube
- Leathrach
- Leberidocysta
- Lebessphaera
- Lebouraia
- Lechuga de samba
- Lecithites
- Leiofusa
- Leioplanktona
- Leiosphaeridia
- Lejeunecysta
- Lejeunia
- Lejolisia
- Lelato
- Lelatu
- Lembergia
- Lemmermannia
- Lemmermanniella
- Lenormandia
- Lenormandiopsis
- Leonardosia
- Lepidochromonas
- Lepidodinium
- Lepidoton
- Lepocinclis
- Lepraria
- Leptochaete
- Leptocystinema
- Leptodiscus
- Leptofauchea
- Leptoklonion
- Leptolyngbya
- Leptomonas
- Leptophyllis
- Leptophyllus
- Leptorima
- Leptosarca
- Leptosiphonia
- Leptosomia
- Leptothamnion
- Lessardia
- Lesueuria
- Letestuinema
- Letterstedtia
- Lettuce laver
- Leukopyxis
- Leuvenia
- Leveillea
- Levringiella
- Liagora
- Liagorophila
- Liagoropsis
- Liagorothamnion
- Lichen belt
- Lichen carrageenin
- Lichen irlandicus
- Limbo-bexiga
- Limnothrix
- Limo-folha
- Limu aalaula
- Limu-aalaulaa
- Limu aki`aki
- Limu aki aki
- Limu eka
- Limu fuafua
- Limu honu
- Limu ho`onunu
- Limu hula hula waena
- Limu huluhu-iuwaena
- Limu huna
- Limu kala
- Limu-kala
- Limu ko'ele'ele
- Limu koeleele
- Limu kohu
- Limu lepe-o-hina
- Limu lepe `ula`ula
- Limu lipaakai
- Limu lipe`epe`e
- Limu lipe'epe'e
- Limu lipoa
- Limu-lipoa
- Limu lko'ele'ele
- Limu lo-loa
- Limu luan
- Limu manauea
- Limu-manauea
- Limu mane`one`o
- Limu nipaakai
- Limu ogo
- Limu pahapaha
- Limu pahe`e
- Limu palahalaha
- Limu papahapapa
- Limu wawae'iole
- Lissodinium
- Litharthron
- Lithocapsa
- Lithococcus
- Litholepis
- Lithomyxa
- Lithonema
- Lithophyllum
- Lithoporella
- Lithothamnion
- Lithothamnium
- Lithothrix
- Lithraphidites
- Lithymenia
- Litosphaeridium
- Lobocystis
- Lobster horns
- Lochmium
- Loefgrenia
- Lohmannia
- Lomathamnion
- Lomentaria
- Long bladder kelp
- Lophocladia
- Lophodiacrodium
- Lophodinium
- Lophopodium
- Lophosiphonia
- Lophosphaeridium
- Lophurella
- Loranthophycus
- Loriella
- Luche
- Lucianorhabdus
- Luciella
- Lukinia
- Lu kio tsai
- Lundiella
- Lychaete
- Lygistes
- Lyngbyopsis
- Lynkiella
- Lysigonium
- Mac con iomaire
- Macromastix
- Macropogon
- Macrothamnion
- Madraí
- Madraí rua
- Maedleriella
- Maedlerisphaera
- Maërl
- Maesaengi
- Ma-funori
- Ma kombu
- Makombu
- Makuri
- Makuri-nori
- Makusa
- Malaconema
- Malleochloris
- Mambiama
- Mammaria
- Manchudinium
- Mantellum
- Maranhites
- Marchesettia
- Marinkjarni
- Marionella
- Maripelta
- Markalius
- Marrocanium
- Marssoniella
- Marsupiogaster
- Martensia
- Maruba-amanori
- Maruba-nori
- Masakia
- Masakiella
- Maschalosporium
- Maschalostroma
- Masloviporidium
- Massartia
- Mastigocladopsis
- Mastigocladus
- Mastigocoleopsis
- Mastigosphaera
- Mastodia
- Mastophoropsis
- Masudaphycus
- Matanomadhia
- Matazaki-kurogashira
- Mateola
- Máthair an duillise
- Matsumo
- Matsunori
- Matteia
- Mayoi-iwanokawa
- May weed
- May-weed
- Mazoyerella
- Mazzaella
- Medeiothamnion
- Meereiche
- Meerespalme
- Meersalat
- Meiodiscus
- Meiourogonyaulax
- Melanamansia
- Melanema
- Melanodinium
- Melanoseris
- Melanothamnus
- Melanthalia
- Melobesia
- Melodinium
- Membranella
- Membranifolia
- Membranilarnacia
- Membranoptera
- Menashi-komou
- Mendicodinium
- Menoidiomonas
- Menoidium
- Meredithia
- Merenia
- Meridiocolax
- Meristiella
- Mermaid's fishing line
- Mermaid’s hair
- Mermaids line
- Mermaid's tresses
- Mermaid's tressses
- Mermaid's wine glass
- Merodinium
- Merrifieldia
- Mesochara
- Mesoporos
- Mesothamnion
- Mesotrema
- Metadoga
- Metagoniolithon
- Metamastophora
- Metamorphe
- Metanema
- Metaphalacroma
- Metapolytoma
- Meyerella
- Michaelsarsia
- Micracanthodinium
- Micraloa
- Micramansia
- Micrhystridium
- Microchara
- Microcladia
- Microcolax
- Microcoleus
- Microcrocis
- Microcystiopsis
- Micropeuce
- Microphyllum
- Microrhabdulinus
- Microrhinus
- Microsporium
- Microstaurus
- Microthoe
- Midori-uzumimo
- Mikamiella
- Mileara
- Millreacha
- Minmaya-kombu
- Minuscula
- Míobhán
- Míoránach
- Misceomarginatus
- Misuishi-kombu
- Mitcheldeania
- Mitsuishi-kombu
- Mitsumata-kurogashira
- Miyeouk
- Mizu-kombu
- Mojaban
- Monasella
- Moniliformia
- Monocercomonas
- Monocercomonoides
- Monocrodium
- Monomarginatus
- Monomorphina
- Monosporus
- Montanoa
- Montemaria
- Mortensenia
- Moto-kombu
- Motozoroi-kombu
- Motsuki-chasômen
- Motsuki-hitoe
- Motsure-gusa
- Motsure-miru
- Mougeotia
- Mougeotiopsis
- Mouse plant
- Mousse d’irelande
- Mousse d'irlande
- Mousse d’irlande
- Mozuka
- Mucus corallinus
- Muderongia
- Mugiwara-nori
- Múirín na muc
- Mukade-nori
- Multipartis
- Multiplicisphaeridium
- Multisiphonia
- Multispirochara
- Munarinus
- Munieria
- Múrach bhealtaine
- Múrach dhubh
- Múrach fómhair
- Muriellopsis
- Murlins
- Murone-amanori
- Murracysits
- Murraycystis
- Murrayella
- Murrayellopsis
- Muschio irlandese
- Musgo
- Musgo gordo
- Musgo-gordo
- Musgos
- Mustard limu
- Mycacanthococcus
- Mychodea
- Mychodeophyllum
- Mycinema
- Mycoidea
- Mycotetraedron
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- Nancythalia
- Nannoceratopsis
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- Nanopera
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- Narrowleaf sargassum weed
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- Natsu-nori
- Nautocapsa
- Nautococcus
- Navisolenia
- Nebarimo
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- Neevea
- Neglectella
- Neglectellopsis
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- Nematodinium
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- Neoabbottiella
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- Nereidea
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- Nesophila
- Net wing
- Neurocaulon
- Neurophyllis
- Neurymenia
- Nexosispinum
- Nienburgella
- Nienburgia
- Nimotsu-kombu
- Nise-futomozuku
- Nise-mozuku
- Nise-tsurumo
- Nitellopsis
- Niu mau tsai
- Nizymenia
- Nodosochara
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- Norrissia
- Nostochopsis
- Nothocladus
- Nothogenia
- Notophycus
- Notosolenus
- Nucellosphaeridium
- Nullipora
- Nuoc-mam
- Nuru
- Nwynea
- Nylandera
- Oar weed
- Oarweed
- Obakusa
- Obana-hanemo
- Ôba-yezobukuro
- Oblea
- Oboro kombu
- Oboro-kombu
- Obtusochara
- Obusa
- Occisucysta
- Ochromallomonas
- Ochrosphaera
- Ochtodes
- Octacanthium
- Octaedryxium
- Octocyclus
- Octopodorhabdus
- Octosporiella
- Odonthalia
- Oginori
- Ogo nori
- Ogo-nori
- O-hitoegusa
- Oicomonas
- Okamurina
- Oka-nori
- Oki-kombu
- Okitsu-nori
- Okkolithus
- Olann dhearg
- Oligochaetophora
- Oligocladella
- Oligosphaeridium
- Oltmannsiella
- Olus marinus
- Oncobyrsa
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- Oneillia
- Oni-amanori
- Oni-amonari
- Onigusa
- Oni-kombu
- Onikusa
- Oni-wakame
- Onkonema
- Ono-nori
- Oocardium
- Oocystaenium
- Oocystella
- Oocystidium
- Oocystopsis
- Oodesmus
- Oolithotus
- Oonephris
- Open sea nori
- Opephyllum
- Operculodinium
- Ophiaster
- Ophidocladus
- Opuntiella
- Orastrum
- Orculifilum
- Orimanthis
- Ortonella
- Oscillaria
- Oscillatoriopsis
- Oseille de mer
- O-shiriomidoro
- Osmundaria
- Osmundea
- Ossiella
- Ostiophyllum
- Ostreopsis
- Ostsee-agar
- Ottavianus
- Oval leaf seagrass
- Ovillaria
- Ovoidinium
- Ovoidites
- Oxytoxum
- Oyakusa
- Oyster thief
- Ozophora
- Ozotobrachion
- Pachyarthron
- Pachychaeta
- Pachycladon
- Pachydasya
- Pachymenia
- Pachymeniopsis
- Pachysphaera
- Paddle weed
- Paddy tang
- Pahapaha
- Pakaiea
- Pakeleaw`a
- Palaeoanacystis
- Palaeocystodinium
- Palaeohydrococcus
- Palaeolyngbya
- Palaeomicrocystis
- Palaeoperidinium
- Palaeophalacroma
- Palaeopontosphaera
- Palaeoscytonema
- Palaeostomocystis
- Palaeowestiellopsis
- Palaiosphaeridium
- Palikiella
- Palisada
- Palmellococcus
- Palmellocystis
- Palmellosphaerium
- Palmentang
- Palmnickia
- Palusphaera
- Pandorella
- Pantoneura
- Papahapaha
- Papenfussia
- Papenfussiomonas
- Pappomonas
- Papposphaera
- Papyracea
- Paracapsa
- Parachaetetes
- Parachrysidalis
- Paracolonnella
- Paraconophyton
- Paracuneatochara
- Paragoniolithon
- Parahistioneis
- Para-kompo
- Paralemanea
- Parallela
- Paramastix
- Paraortonella
- Paraphysomonas
- Paraplectonema
- Parapolytoma
- Paraspora
- Parebriopsis
- Parenchymorpha
- Pareodinia
- Parhabdolithus
- Parmidium
- Parrocelia
- Parthasarathiella
- Parvicorbicula
- Parviphycus
- Parvocavatus
- Parvocysta
- Pascheriella
- Pascherina
- Pascherinema
- Patenocarpus
- Paulsenella
- Paulsilvella
- Pavillardia
- Pavillardinium
- Peacock's tail
- Pearl moss
- Peckichara
- Peckisphaera
- Pectinella
- Pedinomonadopsis
- Pelagothrix
- Peltasta
- Pentapharsodinium
- Pepper dulse
- Percivalia
- Pericystis
- Peridiniella
- Peridiniopsis
- Perikladosporon
- Periphykon
- Periphyllophora
- Peripteropsis
- Perispermon
- Perisseiasphaeridium
- Perithamnion
- Perlmoos
- Permocalculus
- Petalodinium
- Petalomonas
- Petalonema
- Peterfiella
- Petrarhabdus
- Petrocelis
- Petroglossum
- Petrosiphon
- Petrovanella
- Pexisperma
- Peyssonneliopsis
- Phacelocarpus
- Phacochorda
- Phacomyxa
- Phacus
- Phaeocapsa
- Phaeocladia
- Phaeococcus
- Phaeocystis
- Phaeoglossum
- Phaeosiphonia
- Phaeosphaerium
- Phalacroma
- Phanulithus
- Phaxantha
- Pheopolykrikos
- Phialonema
- Philippiella
- Phillipsiella
- Phitycolax
- Phitymophora
- Phloeospora
- Phoracis
- Phormidiochaete
- Phormidium
- Phycastrum
- Phycodrina
- Phycodrys
- Phycolapathum
- Phycophila
- Phycopteris
- Phycoseris
- Phyllacantha
- Phyllactidium
- Phyllaria
- Phyllariochloris
- Phyllocardium
- Phyllona
- Phyllophora
- Phyllophoran
- Phyllotylus
- Phyllymenia
- Physematoplea
- Physidrum
- Physocytium
- Physomonas
- Physotris
- Phytelis
- Phythelios
- Phytodinedria
- Phytodinium
- Picarola
- Pihiella
- Pikea
- Pileidinium
- Pilgeria
- Pilidiocystis
- Piliferosphaera
- Pilinia
- Pingarelhos
- Pinnatifida
- Pinnatiphycus
- Pioca
- Piriformachara
- Pithiscus
- Placentophora
- Placochrysis
- Placoma
- Placorhombus
- Placosphaera
- Plagiodinium
- Plagiorhiza
- Plagiospora
- Planctococcus
- Planktocyanocapsa
- Planktolyngbya
- Planktosphaerella
- Planktothrichoides
- Planktothrix
- Planodinium
- Platoma
- Platychara
- Platychrysis
- Platyclinia
- Platymenia
- Platysiphonia
- Platythamnion
- Playaensis
- Plectoderma
- Plectodinium
- Plectonema
- Plectrophora
- Pleonosporium
- Pleromonas
- Pleurasiga
- Pleurastrosarcina
- Pleuroblepharidella
- Pleuroblepharis
- Pleurocapsa
- Pleuromastix
- Pleuromonas
- Pleurostichidium
- Pleurotaeniopsis
- Pleurothamnion
- Plocamiocolax
- Plocamium
- Plocaria
- Ploeotia
- Ploeotila
- Plumaria
- Plumariella
- Plumariopsis
- Pneophyllum
- Pocillomonas
- Pocockiella
- Podamphoropsis
- Podocapsa
- Podohedra
- Podolampas
- Podorhabdus
- Pod-weed
- Pogonophorella
- Poikilofusa
- Pollexfenia
- Polonosphaeridium
- Polyasterias
- Polyblepharides
- Polycavernosa
- Polychaetophora
- Polychlamydum
- Polychroma
- Polycoelia
- Polycoryne
- Polycrater
- Polycystis
- Polygonifera
- Polygonium
- Polyides
- Polykrikos
- Polyneura
- Polyneurella
- Polyneuropsis
- Polyopes
- Polyostea
- Polyphacum
- Polyphysa
- Polyporolithon
- Polysperma
- Polysphaera
- Polysphaeridium
- Polystrata
- Polythrix
- Polytretus
- Polyzonia
- Pomatodinium
- Pompom kelp
- Pontosphaera
- Popping wrack
- Popweed
- Poricalyptra
- Poritectolithus
- Porochara
- Porolithon
- Porotheca
- Porphyran
- Porphyridium
- Porphyrodiscus
- Porphyroglossum
- Porphyropsis
- Porphyrostromium
- Portphillipia
- Postprorocentrum
- Poteriodendron
- Pouchetia
- Powdered kombu
- Pratjetella
- Precious sea grass
- Predaea
- Preperidinium
- Prescottiella
- Prickly tang
- Primorivularia
- Pringsheimia
- Prinsius
- Prionitis
- Priscogalea
- Prochlorothrix
- Prodinophysis
- Prolifera
- Prolixosphaeridium
- Promallomonas
- Pronoctiluca
- Properidinium
- Prosoaulax
- Proterendothrix
- Proterythropsis
- Protoaceromonas
- Protoceratium
- Protococcus
- Protodinifera
- Protodinium
- Protogonyaulax
- Protokuetzingia
- Protoleiosphaeridium
- Protoochromonas
- Protoodinium
- Protoperidinium
- Protopsis
- Protosphaeridium
- Provasoliella
- Psammococconeis
- Pseliodinium
- Psephotaxus
- Pseudanabaena
- Pseudoanemonia
- Pseudobangia
- Pseudobranchioglossum
- Pseudocapsa
- Pseudoceratium
- Pseudochantransia
- Pseudochlorangium
- Pseudochlorococcum
- Pseudochromulina
- Pseudococcomyxa
- Pseudodictyon
- Pseudogirvanella
- Pseudogymnosolen
- Pseudoholopedia
- Pseudolaingia
- Pseudolatochara
- Pseudolessonia
- Pseudolithophyllum
- Pseudomallomonas
- Pseudomicromarsupium
- Pseudomoellerina
- Pseudonostoc
- Pseudopedinomonas
- Pseudoperanema
- Pseudopfiesteria
- Pseudophalacroma
- Pseudophormidium
- Pseudophycodrys
- Pseudoprostratum
- Pseudoquadrigula
- Pseudorhododiscus
- Pseudoschizomeris
- Pseudoscinaia
- Pseudoscytonema
- Pseudostruvea
- Pseudotetraspora
- Pseudotetrastrum
- Pseudothecadinium
- Psilosiphon
- Psilothallia
- Pterigospermum
- Pterocaulon
- Pterocladia
- Pterocladiella
- Pterocladiophila
- Pterocladiopsis
- Pterodictyon
- Pterosiphonia
- Pterospermopsis
- Pterothamnion
- Ptilocladia
- Ptilocladiopsis
- Ptilonia
- Ptilophora
- Ptilota
- Ptilothamnion
- Ptilothamnionopsis
- Ptychodiscus
- Pugetia
- Pulchrasphaera
- Pulvinaster
- Pulvinia
- Pulvinularia
- Punalevä-laji
- Punalevä-suku
- Purdoy
- Purple funori
- Purple nori
- Purple vegetable
- Pycnophycus
- Pyramichlamys
- Pyramidodinium
- Pyramidomonas
- Pyrgidium
- Pyrocystis
- Pyrodinium
- Pyrophacus
- Pyrophyllon
- Quadrichloris
- Quadricoccus
- Quaternariella
- Qunbar al-ma
- Qun dai cai
- Raa-ts
- Rabeiro
- Rabo-negro
- Raciborskia
- Radaisia
- Radaisiella
- Radiathamnion
- Radicilingua
- Radiocystis
- Radioramus
- Raif
- Rainbow bladderweed
- Ramicrusta
- Ramsaya
- Raphidiopsis
- Raphidium
- Raphidonema
- Raphidonemopsis
- Raskyaechara
- Ratanho
- Rau-cau
- Rau cÂu
- Rayssiella
- Réaban
- Red call
- Red eyelet silk
- Red fringe
- Red fucus
- Red jabot laver
- Red kale
- Red kall
- Red laver
- Red limu
- Red nori
- Red rust
- Red ware
- Reed falling stars
- Reimerothrix
- Reinboldia
- Reinboldiella
- Reingardia
- Reinhardtites
- Reinschiella
- Renouxia
- Reptataxis
- Retecapsa
- Reticulobotrys
- Reticulocaulis
- Reticulofenestra
- Reticulosphaera
- Retisphaeridium
- Retusochara
- Rexia
- Rhabdogloea
- Rhabdolekiskus
- Rhabdolithina
- Rhabdolithus
- Rhabdomonas
- Rhabdonia
- Rhabdosphaera
- Rhaphidium
- Rhinodinium
- Rhipidodesmis
- Rhipidothamnion
- Rhizaspis
- Rhizenteron
- Rhizochrysidopsis
- Rhizoglossum
- Rhizolamiella
- Rhizomonas
- Rhizophydium
- Rhizophyllis
- Rhizophyllum
- Rhizopogonia
- Rhizothallus
- Rhodachlya
- Rhodaphanes
- Rhodocallis
- Rhodochaete
- Rhodocladia
- Rhododactylis
- Rhododermis
- Rhododictyon
- Rhododiscus
- Rhododraparnaldia
- Rhodoglossum
- Rhodogorgon
- Rhodolachne
- Rhodolophia
- Rhodomela
- Rhodomelopsis
- Rhodomenia
- Rhodopeltis
- Rhodophyllis
- Rhodophysema
- Rhodophysemopsis
- Rhodoplax
- Rhodoplexia
- Rhodoptilum
- Rhodosaccion
- Rhodosorus
- Rhodospora
- Rhodostichus
- Rhodothamniella
- Rhodymenia
- Rhodytapium
- Rhombocystis
- Rhynchococcus
- Rhynchopus
- Ribbon kelp
- Ribbon-kelp
- Ribíní
- Ricardia
- Richelia
- Richteriella
- Riementang
- Rimuroa
- Riquetophycus
- Ririppus
- Ríseach
- Rishiri-kombu
- Rissoella
- Rivularia
- Rivulariopsis
- Roasted kombu
- Roccálach
- Rock moss
- Rock weed
- Rockweeds
- Rødalge-slaegt
- Røde klude
- Rodriguezella
- Roschera
- Roscoffia
- Rose nori
- Rothella
- Royal kombu
- Ruabhánach
- Ruadhálach
- Ruadhánach
- Ruálach
- Ruánach
- Rucinolithus
- Rufa
- Rufaí
- Rufusiella
- Rugulopteryx
- Rumoi-iwanokawa
- Rupán
- Ruprechtiella
- Russellia
- Ruttnera
- Ruwe agar
- Rytiphlaea
- Ryukyu-mirumodoki
- Ryukyu-tsunomata
- Sabulodinium
- Saccha
- Sacconema
- Sacheria
- Sacol green
- Sagarame
- Sägetang
- Saharifusa
- Sahlingia
- Saimatsu-kombu
- Saimi
- Sajur laut
- Sakhalin agar
- Salpingoeca
- Sangirellum
- Sarcinochlamys
- Sarcocladia
- Sarcodia
- Sarcodiotheca
- Sarcomenia
- Sarconema
- Sarcophycus
- Sarcophyllis
- Sarcothalia
- Sarcotrichia
- Sarfatiella
- Sargassum weed
- Sarumen
- Saturnella
- Saw wrack
- Scagelia
- Scageliopsis
- Scagelonema
- Scagelothamnion
- Scampanella
- Scaphodinium
- Scaphospora
- Schimmelmannia
- Schizochlaenion
- Schizochytriodinium
- Schizocystia
- Schizodictyon
- Schizoglossum
- Schizogonium
- Schizoneura
- Schizosiphon
- Schizothrix
- Schizymenia
- Schmidleinema
- Schmitziella
- Schotentang
- Schottera
- Schuettiella
- Schulziella
- Schweinetang
- Sciadium
- Sciadophycus
- Scinaia
- Sciurothamnion
- Sclernax
- Sclerococcus
- Sclerodinium
- Scopulonema
- Scorpiura
- Scothach
- Scotiella
- Scotiellocystis
- Scotinosphaera
- Scotlandella
- Screadhbhuidhe
- Scriniodinium
- Scrippsiella
- Scutarius
- Scyphosphaera
- Scytochloria
- Scytomonas
- Scytonematopsis
- Sea bamboo
- Sea banner
- Sea belt
- Sea cauliflower
- Sea club
- Sea fir
- Sea fir needle
- Sea girdle
- Sea girdles
- Sea-grass
- Seagriefia
- Sea haricots
- Sea ivy
- Sea-ivy
- Sea lace
- Sea laces
- Sea-lettuce.
- Seamuisin
- Sea mustard
- Sea noodles
- Sea onion
- Sea otter's cabbage
- Sea pearl moss
- Sea petals
- Searlesia
- Sea rods
- Sea rose
- Sea sac
- Sea sorrel
- Sea spaghetti
- Sea spatula
- Sea string
- Sea tail
- Sea thong
- Seatwine
- Sea wand
- Sea ware
- Seaweed meal
- Sea whistle
- Sebdenia
- Sedoidea
- Seguenzaea
- Seirospora
- Seiyohabanori
- SeiyÔ-hahanori
- Selenochloris
- Selenoderma
- Selenodictyon
- Selenosphaerium
- Seletonella
- Semnocarpa
- Sentusidinium
- Septorella
- Seribiscutum
- Serpenomonas
- Serpent kelp
- Serrated wrack
- Serraticardia
- Sestosoma
- Sewing thread
- Shamani kombu
- Sheep dulse
- Sheep's weed
- Shelldulse
- Shepleya
- Shih shun
- Shihua
- Shikin-nori
- Shima-kombu
- Shinori-kombu
- Shiohoshi-kombu
- Shio-kombu
- Shirago-kombu
- Shirio-midoro
- Shiro-tororo
- Shreaded kombu
- Siderocelis
- Siderocystis
- Siderocystopsis
- Signiosphaera
- Silketare
- Sinaiella
- Sinamonas
- Singapore weed
- Sinkoraena
- Sinodinium
- Sinophysis
- Sinosiphonia
- Sinotubimorpha
- Siphonoclathrus
- Siphononema
- Siphorus
- Siphytus
- Sirocladium
- Sirocoleum
- Sirodotia
- Sirogonium
- Sirophysalis
- Sirosiphon
- Skadovskiella
- Skeletonella
- Skeletonemopsis
- Skiagia
- Skujaella
- Skvortzoviella
- Slack marrow
- Slat mara
- Slat mhara
- Sleabhac dearg
- Sleabhach
- Sleabhán
- Sleadaí
- Slender sea lettuce
- Sloak
- Slobán
- Sloke
- Slook
- Small perennial kelp
- Smelltang
- Smithora
- Snowella
- Soesoe lopek
- Sokolovia
- Söl
- Søl
- Solenia
- Solenicola
- Solenodinium
- Solentia
- Solieria
- Solisphaera
- Somewake-gusa
- Sommierella
- Sonderia
- Sonderopelta
- Sopaushi
- Sorella
- Sorocarpus
- Soropediastrum
- Sou sol
- Sou-söll
- Spaghetti de mer
- Spatulodinium
- Spelaeopogon
- Spermipole
- Sphaenosiphon
- Sphaerastrum
- Sphaeripara
- Sphaerobotrys
- Sphaerocalyptra
- Sphaerocarpus
- Sphaerocavum
- Sphaerochara
- Sphaerochrysella
- Sphaerodictyon
- Sphaerodictyton
- Sphaerodinium
- Sphaerogonium
- Sphaerophycus
- Sphaeroplethia
- Sphaerospermum
- Sphaerozyga
- Sphenolithus
- Sphenomonas
- Sphondylothamnion
- Spinasphaera
- Spiniferites
- Spiniferodinium
- Spinocosmarium
- Spinosum
- Spinularius
- Spirillopsis
- Spirirestris
- Spirochrysis
- Spirocladia
- Spirodinium
- Spirogonium
- Spiromonas
- Spirophycus
- Split whip wrack
- Spondylomorum
- Sponge seaweed
- Sponge tang
- Sponge weed
- Spongioplastidium
- Spongites
- Spongocladia
- Spongodendron
- Spongodium
- Spongomorpha
- Spongopsis
- Sporodinium
- Sporoglossum
- Sporolithon
- Sporotetras
- Spúinse
- Spyridia
- Spyridiocolax
- Squamaria
- Squamolithon
- Sraith bhuí
- Sraoilleach
- Sreanga
- Stacheltang
- Starria
- Staurocarpus
- Staurogenia
- Staurolithites
- Stauromatonema
- Staurophanum
- Staurospermum
- Steen-or klipbloem
- Stegengaea
- Steiniella
- Stellatochara
- Stelliferidium
- Stenhinna
- Stenocladia
- Stenogramme
- Stephanochara
- Stephanocodon
- Stephanocoelium
- Stephanocomium
- Stephanocystis
- Stephanoeca
- Stephanoon
- Stephanoporos
- Stephanoptera
- Stereococcus
- Sterrocladia
- Sterrocolax
- Stichocarpus
- Stichophora
- Stichosiphon
- Stichothamnion
- Stictophyllum
- Stictosiphonia
- Stigonema
- Stilocapsa
- Stiphrosphaeridium
- Stipites laminariae
- Stir fry seaweed
- Stokktare
- Stomatochroon
- Stomochara
- Stradnerlithus
- Strap wrack
- Strapwrack
- Streblocladia
- Streptonema
- Striatomarginis
- Striatotheca
- Stringy kelp
- Stromatocarpus
- Strombomonas
- Stumpa
- Stylodinium
- Stylonema
- Stylopyxis
- Stylosphaeridiella
- Stylotheca
- Sugara
- Sugar sea belt
- Sugar tang
- Sugar wrack
- Sugarwrack
- Suhria
- Sui song
- Sujime
- Sukkertare
- Sullivania
- Summer seaweed
- Supreme limu
- Surculosphaeridium
- Surikogidzuta
- Susabi-nori
- Susab-nori
- Sushi nori
- Swarchewskiella
- Sweet tangle
- Sweet wrack
- Swine tang
- Sycamina
- Sycidium
- Syltodinium
- Symbiococcum
- Symphoricoccus
- Symphyocladia
- Symphyonemopsis
- Symphyosiphon
- Symplassosphaeridium
- Symploca
- Symplocastrum
- Sympodothamnion
- Synarthrophyton
- Synchroma
- Synochromonas
- Syracosphaera
- Syringocolax
- Systematophora
- Taborrão
- Taenioma
- Tahalib
- Tahmuck
- Tai tso
- Tai tyau
- Taiwan-ogonori
- Talaroneis
- Tama-juzumo
- Tama-no-ito
- Tambalang
- Tambalang green
- Tambalang milo
- Tambalang putan
- Tamba-nori
- Tanakaella
- Tanmae
- Tanyosphaeridium
- Tapeinodasya
- Tapinothrix
- Tariccrodium
- Tarugata-juzumo
- Tasima
- Tasmanites
- Tayloriella
- Taylorophycus
- Tectatodinium
- Tectochara
- Tecuitlatl
- Teichorhabdus
- Teilingia
- Tellesk
- Temnogametum
- Temnogyra
- Tenaciphyllum
- Tenarea
- Tender kelp
- Tender kombu
- Tengusa
- Tengusa-agar
- Tertiariopsis
- Teshio-kombu
- Tethysicodium
- Tetrablepharis
- Tetrachloris
- Tetradinium
- Tetragonium
- Tetralithoides
- Tetralithus
- Tetramerosphaera
- Tetranema
- Tetranephris
- Tetrapodorhabdus
- Tetrarcus
- Tetrasporella
- Tetrathamnion
- Tetratoma
- Tetratomococcus
- Tetreutreptia
- Thack hoa
- Thalassiphora
- Thalassodendron
- Thalpophila
- Thamnocarpus
- Thamnoclonium
- Thamnophora
- Thamnophyllis
- Thaumatodinium
- Thaurilens
- Thecadiniopsis
- Thecadinium
- Thelesphaera
- The maura
- Thermosynechococcus
- Thiersteinia
- Thin dragon beard plant
- Thin snow kombu
- Thiochaete
- Thompsodinium
- Thonged
- Thongweed
- Thoracomonas
- Thoracosphaera
- Thorakochloris
- Thorosphaera
- Threadweed
- Thuretella
- Thuretellopsis
- Thuretia
- Thysanocladia
- Tichocarpus
- Tielingella
- Tiffaniella
- Tikvahiella
- Titanoderma
- Titanophycus
- Tocoroten
- Toge-tsunomata
- Toge-urushigusa
- Togula
- Tokachi-kombu
- Tokidadendron
- Tokidaea
- Tokoroten
- Tokoro-tengusa
- Tolypella
- Tolypellopsis
- Tolypiocladia
- Tolypothrix
- Tomaculum
- Tomoe-nori
- Toriashi
- Toriashi-agar
- Torodinium
- Tororo kombu
- Tororo-kombu
- Tortitaenia
- Tou fah tsai
- Tou mau tsai
- Tovellia
- Trailliella
- Trambolho
- Trapezopentus
- Trematocarpus
- Trematosphaeridium
- Treptacantha
- Triadinium
- Trichidium
- Trichloridella
- Trichoceras
- Trichocladia
- Trichocoleus
- Trichodinium
- Trichogloea
- Trichogloeopsis
- Trichothamnion
- Trichothyra
- Tricleocarpa
- Trigenea
- Trigonaspis
- Trigonidiella
- Trilobatum
- Trinitaria
- Trinovantedinium
- Triplastrum
- Tripodiscus
- Triposolenia
- Triquetrorhabdulus
- Trithamnion
- Trochiliscus
- Trochodinium
- Tropidoneis
- Tropidoscyphus
- Truncatulus
- Tryponema
- Tschintschau
- Tschoo-hoae
- Tsengia
- Tsu choj
- Tsukomo nori
- Tsukomo-nori
- Tsukushi-amanori
- Tsunomata
- Tsuruarame
- Tsurumo
- Tsu tsai
- Tsu tsoi
- Tsz tsai
- Tuberculodinium
- Tubiella
- Tuomeya
- Turbochara
- Turkish towel
- Turkish twel
- Turnerella
- Turrilithus
- Turrisphaera
- Tussetia
- Tychonema
- Tyleiophora
- Tylochrysis
- Tylotopalla
- Uchi kombu
- Ufer-borstenhaar
- Uikyô-mo
- Ulopteryx
- Ulotrichella
- Ulotrichopsis
- Ulte
- Ululania
- Ulvella
- Umbellosphaera
- Umezakia
- Umi-somen
- Umisomen
- UmisÔmen
- Umiyama-kombu
- Uncinisphaera
- Uniplanarius
- Uppurui-nori
- Urakawa-kombu
- Urceolus
- Uredo
- Urnella
- Uruppui-nori
- Urushi-gusa
- Ushi-ke-nori
- Uvella
- Vagalapilla
- Vaginaria
- Valensiella
- Vanguard giant
- Vanvoorstia
- Varech vésiculeux
- Vaughaniella
- Vekshinella
- Veleroa
- Verdigellas
- Verrucaria
- Veryhachium
- Vesicophycus
- Vesillarius
- Vickersia
- Virgatasporites
- Voleuse d'huitres
- Volubilaria
- Vortetang
- Voukiella
- Vulcanisphaera
- Waernia
- Wakamé
- Wakaoi
- Waldoia
- Wangichara
- Warakuzumo
- Warnowia
- Warrenia
- Watamo
- Water silk
- Watznaueria
- Wawae`iole
- Weberella
- Webervanbossea
- Wedgeshaped chainweed
- Weeksia
- Westellopsis
- Westiella
- Westiellopsis
- Wetherbeella
- Wetzeliella
- Whidbeyella
- White kombu
- White-pulpy kombu
- White wrack
- Wigwamma
- Wildemania
- Willea
- Willeella
- Wing kelp
- Wiseorhabdus
- Woelkerlingia
- Wollastoniella
- Wollea
- Wolliger seequirl
- Wolskyella
- Womersleyella
- Woody chain bladder
- Wormskioldia
- Woronichinia
- Wrangelia
- Wrightiella
- Wurdemannia
- Xainzanella
- Xandarodinium
- Xanthophycomonas
- Xenicodinium
- Xenococcus
- Xenotholos
- Xoa xoa
- Yadori-midoro
- Yalisphaeridium
- Yamadaella
- Yamadaia
- Yamadaphycus
- Yanagi-funori
- Yanagi-moku
- Yan tsai
- Yatabella
- Yayan-kombu
- Yego nori
- Yendonia
- Yezo-bukuro
- Yezo-hitoegusa
- Yezo-ishige
- Yezo-iwahige
- Yezo-kashirazaki
- Yezo-miru
- Yezo-mozuku
- Yimaocai
- Yonagunia
- Yonedaella
- Yore-kayamo
- Yoremoku-modoki
- Yotsuba-gusa
- Yuikiri
- Yuyucho
- Zanardinula
- Zanzibar weed
- Zarame
- Zellera
- Zeugrhabdotus
- Zi-cai
- Zicai
- Zierliche seefederf
- Zignoa
- Zonariophila
- Zonotrichites
- Zottige meersaite
- Zuckertang
- Zygabikodinium
- Zygnema
- Zygnemopsis
- Zygodiscus
- Zygogonium
- Zygolithus
- Zygoselmis
- Zygosphaera
