A group of wildflowers native to Ireland but mainly absent from Britain form what is known as the 
Lusitanian Flora.  
This unique collection of mediterranean plants came originally from the Iberian Peninsula (North Spain and Portugal), 
and in Ireland most are found in the South and West. 
It is unlikely that they have survived from before the last Ice Age but there is no conclusive explanation for their presence here.
 Maidenhair Fern, Adiantum capillus-veneris, Duchosach: Co. Clare, Galway, Mayo
  
Maidenhair Fern, Adiantum capillus-veneris, Duchosach: Co. Clare, Galway, Mayo 
 Fringed/Irish Sandwort, Arenaria ciliata, Gaineamhlus gaelach: Co. Sligo
  
Fringed/Irish Sandwort, Arenaria ciliata, Gaineamhlus gaelach: Co. Sligo
 Strawberry Tree, Arbutus unedo, Caithne: Co. Kerry, Sligo, W Cork
  
Strawberry Tree, Arbutus unedo, Caithne: Co. Kerry, Sligo, W Cork	
 St Dabeoc's Heath, Daboecia cantabrica, Fraoch na haon choise: West Galway, Mayo
  
St Dabeoc's Heath, Daboecia cantabrica, Fraoch na haon choise: West Galway, Mayo 
 Irish Heath, Erica erigena, Fraoch camógach: Co. Galway, Mayo
  
Irish Heath, Erica erigena, Fraoch camógach: Co. Galway, Mayo
 Mackay's Heath, Erica mackaiana, Fraoch mhic aoidh: Co. Donegal, Connemara
  
Mackay's Heath, Erica mackaiana, Fraoch mhic aoidh: Co. Donegal, Connemara
 Irish Eyebright, Euphrasia salisburgensis, Glanrosc gaelach: Western Ireland
  
Irish Eyebright, Euphrasia salisburgensis, Glanrosc gaelach: Western Ireland
 Irish Spurge, Euphorbia hyberna, Bainne caoin: Western Ireland
  
Irish Spurge, Euphorbia hyberna, Bainne caoin: Western Ireland
 Irish Fleabane, Inula salicina, Lus gréine gaelach: Lough Derg, N Tipperary
  
Irish Fleabane, Inula salicina, Lus gréine gaelach: Lough Derg, N Tipperary
 Recurved Sandwort, Minuartia recurva, Gaineamhlus cuar: Co. Kerry, W Cork and Waterford
  
Recurved Sandwort, Minuartia recurva, Gaineamhlus cuar: Co. Kerry, W Cork and Waterford
 Dense-flowered Orchid, Neotinea maculata, Magairlín glas: Western Ireland and E Cork
  
Dense-flowered Orchid, Neotinea maculata, Magairlín glas: Western Ireland and E Cork 
 Large-flowered Butterwort, Pinguicula grandiflora, Leith uisce: SW Cork, Limerick, Clare, Aran Islands
  
Large-flowered Butterwort, Pinguicula grandiflora, Leith uisce: SW Cork, Limerick, Clare, Aran Islands
 Kidney Saxifrage, Saxifraga hirsuta, Morán giobach: Co. Kerry, W Cork
  
Kidney Saxifrage, Saxifraga hirsuta, Morán giobach: Co. Kerry, W Cork
 St Patricks Cabbage, Saxifraga spathularis, Cabáiste an mhadra rua: W Ireland, also Co. Waterford
  
St Patricks Cabbage, Saxifraga spathularis, Cabáiste an mhadra rua: W Ireland, also Co. Waterford 
 Kerry Lily, Simethis mattiazzii, Lile fhíonáin: Co. Kerry
  
Kerry Lily, Simethis mattiazzii, Lile fhíonáin: Co. Kerry
 
North American species: 
There is one North American species that is native to Ireland but not found in Britain or Europe, and three which are found in Ireland and Britain but not elsewhere in Europe.
 Irish St Johnswort, Hypericum canadense, Beathnua gaelach: Co. Cork, W Galway, W Mayo
  	
Irish St Johnswort, Hypericum canadense, Beathnua gaelach: Co. Cork, W Galway, W Mayo	
 Blue-eyed Grass, Sisyrinchium bermudiana, Feilistrín gorm: SW, NW Ireland. Scattered UK distribution
  	
Blue-eyed Grass, Sisyrinchium bermudiana, Feilistrín gorm: SW, NW Ireland. Scattered UK distribution	
 Pipewort, Eriocaulon aquaticum, Pípín uisce: Western Ireland, also Inner Hebrides, 
W Scottish mainland
  	
Pipewort, Eriocaulon aquaticum, Pípín uisce: Western Ireland, also Inner Hebrides, 
W Scottish mainland
 Irish Ladys-tresses, Spiranthes romanzoffiana, Cuílín gaelach: SW, W, NE Ireland, also Inner Hebrides, Western Scotland
  	
Irish Ladys-tresses, Spiranthes romanzoffiana, Cuílín gaelach: SW, W, NE Ireland, also Inner Hebrides, Western Scotland