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Circaea lutetiana – Enchanter's-nightshade
Species, Flowering plant, Freshwater
Common Enchanter's Nightshade, Enchanter's Nightshade, Llysiau Steffan, Llys Steffan Cyffredin, Gedor-Wrach, Llys Steffan, Mochlys Duon, Mochlys Swynyddlys, Swynyddlys, Llysiau'r Swynwr, Llysiau Ystyffan, Swynlys
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Cirsium arvense – Creeping Thistle
Species, Flowering plant, Freshwater
Llawegor, Ysgallen Llusg-Wraidd, Ysgallen y Maes, Ysgallen Gyffredin, Ysgallen Gwraidd Rhedegog, Ysgall y Maes, Ysgallen yr Ŷd, Ysgallen Gyffredin yr Âr
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Cirsium dissectum – Meadow Thistle
Species, Flowering plant, Freshwater
Ysgallen Mignwern, Ysgallen y Ddôl, Ysgallen Gorswaun, Ysgall y Ddôl
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Cirsium palustre – Marsh Thistle
Species, Flowering plant, Freshwater
Marchysgall y Gors, Ysgallen y Gors, Ysgallen Gweirglodd Wlyb, Ysgall y Gors
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Cirsium vulgare – Spear Thistle
Species, Flowering plant, Freshwater
March Ysgall, Ysgall Gwyllt, Ysgall Gwylltion, Marchysgallen, March Ysgallen, Marchysgall, Ysgallen Goronog, Ysgall y Blaidd, Marchysgall Berog, Ysgallen y Blaidd, Ysgall Wyllt, Ysgall y Tarw
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Cladium mariscus – Great Fen-sedge
Species, Flowering plant, Freshwater
Fen Sedge, Saw Sedge, Hesgen y Gors, Pibfrwynen, Llymdreiniog, Llemfrwynen, Corsfrwynen Lem, Corsfrwynen
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Corrigiola litoralis – Strapwort
Species, Flowering plant, Freshwater
Y Gorglymog, Corglymig, Canclymig
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Corylus avellana – Hazel
Species, Flowering plant, Freshwater
Hazelnut, calltainn, Collen, Pren Cnau, Collwyn, Cyll, Coll-Lwyn
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Crassula aquatica – Pigmyweed
Species, Flowering plant, Freshwater
Luibh Beag Bìodach, Corchwyn
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Crepis paludosa – Marsh Hawk's-beard
Species, Flowering plant, Freshwater
Heboglys y Gors, Gwalchlys y Gors
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Cuscuta epithymum – Dodder
Species, Flowering plant, Freshwater
Lesser Dodder, Common Dodder, Llinclwm, Cyfnydd, Llindro Lleiaf, Llindag Lleiaf, Llindag
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Cyperus fuscus – Brown Galingale
Species, Flowering plant, Freshwater
Black Cyperus, Brown Cyperus, Ysnoden Fair Lwytgoch, Ysnoden-Fair Lwytgoch
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Cyperus longus – Galingale
Species, Flowering plant, Freshwater
Sweet Galingale, Ysnoden Fair
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Cytisus scoparius – Broom
Species, Flowering plant, Freshwater
bealaidh, bealaidhean, Banadl Cyffredin, Banadl, Banadlen, Banhadlen, Manal, Ysgubell Fanal, Banhalen, Banhallen
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Dactylis glomerata – Cock's-foot
Species, Flowering plant, Freshwater
Cocksfoot, Troed y Ceiliog, Grugwellt, Dant y Ci, Byswellt Garwaidd, Byswellt
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Dactylorhiza fuchsii – Common Spotted-orchid
Species, Flowering plant, Freshwater
Tegeirian Brych Cyffredin, Tegeirian Mannog Byseddog, Tegeirian Mannog, Tegeirian Brych, Tegeiriau Brych
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Dactylorhiza incarnata – Early Marsh-orchid
Species, Flowering plant, Freshwater
Early marsh orchid, Tegeirian y Gors, Mogairlean Lèana, Tegeirian Rhuddgoch, Tegeirian-y-Gors Cynnar
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Dactylorhiza kerryensis – Western Marsh-orchid
Species, Flowering plant, Freshwater
Broad-Leaved Marsh Orchid, Tegeirian Llydanddail y Gors, Tegeirian-y-Gors Llydanddail
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Dactylorhiza maculata – Heath Spotted-orchid
Species, Flowering plant, Freshwater
Gwialen y Gŵr Ifanc, Tegeirian Mannog Byseddog, Tegeirian Brych, Tegeirian Brych y Rhos, Tegeirian Mannog y Grugdir
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Dactylorhiza praetermissa – Southern Marsh-orchid
Species, Flowering plant, Freshwater
Tegeirian y Gors Deheuol, Tegeirian y Gors, Tegeirian-y-Gors Deheuol