ENTRIES START
Below you can find links to the various (natural & artificial) groups of Icelandic plant species. From there you can identify single species and find the information on that species.

  Ferns: Club mosses, Horsetails and True Ferns


The ferns consists of three basic groups:
1) the  clubmosses: more or less creeping stems with small dense foliage.
2) the  horsetails: typically plants with a leafless stems or a stems from which spread needle like side branches. Spore forming organs are conically placed on the top of the stems.
3) the  true ferns (leafy plants, leaves (fronds) are usually divided in leaflets. Stems very short usually not visible. The spore forming organs are normally on the bottom side of the leaves.


Below are the links to information on specific clubmoss species

Alpine Clubmosses
Lycopodium alpinum
Interrupted Clubmoss
Lycopodium annotinum
Fir Clubmoss
Huperzia selago
Lesser Clubmoss
Selaginella selaginoides

Next the links to information on specific horsetail species

(1) Horsetail species with branched stems. These branches are placed in whorls around the main stem

Field Horsetail
Equisetum arvense
Shady Horsetail
Equisetum pratense
Marsh Horsetail
Equisetum palustre
Wood Horsetail
Equisetum sylvaticum

(2) Horsetail species lacking side branches from the main stem

Marsh Horsetail
Equisetum palustre
Water Horsetail
Equisetum fluviatile
Variegated Horsetail
Equisetum variegatum
Rough Horsetail
Equisetum hyemale

Note that E. palustre (marsh horsetail) is in both series; that is because at first it may seem to be without lateral branches but later on during the season it clearly does have lateral branches.


And now the links to information on specific true fern species
1): Single leaves not disected in leaflets or compound leaves having only first order leaflets (meaning the leaves are disected only once in a row - these first order leaflets are not disected any further)

Common Moonwort
Botrichium lunaria
Common Polypody
Polypodium vulgare
Holly Fern
Polystichum lonchitis
Oblong Woodsia Fern
Woodsia ilvensis

2): leaves disected at least twice in a row

Brittle Bladder-fern
Cystopteris fragilis
Oak Fern
Gymnocarpium dryopteris
Lady Fern
Athyrium filix-femina
Alpine Lady Fern
Athyrium distentifolia
Beech Fern
Phegopteris connectilis


  Birches, Willows, Juniper & Poplar.


Woody species excluding willows:

Juniper
Juniperus communis
Downy Birch
Betula pubescens
Dwarf Birch
Betula nana
Rowan tree
Sorbus aucuparia
Aspen
Populus tremula

Willow species:

Dwarf Willow
Salix herbacea
Wooly Willow
Salix lanata
Arctic Willow
Salix arctica
Tea-leaved Willow
Salix phylicifolia


  Heather family: heathers, related berry species and wintergreen species


Heath species (1): Crowberry (Empetrum), Common heather (Calluna) and other heather species species:

Crowberry
Empetrum nigrum
Common Heather
Calluna vulgaris
Blue Heath
Phyllodoce coerulea
Trailing azalea
Loiseleuria procumbens
Mossy Mountain-heather
Harrimanella hypnoides
= Cassiope hypnoides

Heather species (2): Arctostaphylos (bearberry) and Vaccinium species:

Bearberry
Arctostaphylos uva-ursi
Northern/Bog Bilberry
Vaccinium uliginosum
Bilberry
Vaccinium myrtillus
Small Cranberry
Vaccinium microcarpum

Wintergreen species: (Note: the Pyrola and Orthillia species {wintergreen's} have been regarded as members of their own family - Pyrolaceae. Recent genetic studies lead specialists to conclude that they have to be included in the Ericaceae = heather family).

Common Wintergreen
Pyrola minor
Arctic Wintergreen
Pyrola grandiflora
Serrated Wintergreen
Orthilia secunda



  Herbs, flowers have free petals (1): Dock, Goosefoot Purslane and Nettle family species


The choripetalae are large group of herbs. In this section three related families are treated: the dock/sorrel, the goosefoot and the purslane family.

Dock / Sorrel family:(Polygonaceae): Rather small reddish or white flowers clustered in dense inflorescenses.

Mountain sorrel
Oxyria digyna
Common sorrel
Rumex acetosa
Sheep's Sorrel
Rumex acetosella
Northern Sorrel
Rumex longifolius
Knotgrass
Polygonum aviculare
Iceland-purslane
Koenigia islandica
Alpine bistort
Bistorta vivipara
Rhubarb
Rheum sp.

Goosefoot, Purslane aned Nettle families:

Babingtons's Orache
Atriplex glabriuscula
Blinks
Montia fontana
Common Nettle
Urtica dioica

  Goosefoot family (Chenopodiaceae): On Iceland there is just one common species. It is a coastal plant often growing on sandy beach soils over flood deposits. Small inconspicuous green or reddish flowers grouped together.
  Purslane family (Portulacaceae): Also one common species on Iceland: Montia fontana (Blinks). Note there is also a plant called Iceland-purslane. Contrary to what the name suggests, this is not a member of the purslane family but it belongs to the dock family (see above).
 Nettle family (Urticaceae): The nettle family is represented by two introduced weedy species. They are regarded as "aliens".



  Herbs, flowers with free petals (2): Saxifrage & Stonecrop family


Saxifrage family (Saxifragaceae): Starry flowers usually (creamy-)white but two species are yellow and one purple. The calyx is often fused at the bottom. For identification the family is split in three series: being the non-white flowering members of the Saxifraga genus plus the white flowering "Grass of Parnassus" (Parnassia palustris). The latter is member of the Saxifraga family but not a true Saxifraga, The second and third list present the white flowering Saxifraga's. It is easy to change the lists within any page though.

Grass of Parnassus
Parnassia palustris
Marsh Saxifrage
Saxifraga hirculus
Yellow Saxifrage
Saxifraga aizoides
Purple Saxifrage
Saxifraga oppositifolia
Pyramidal Saxifrage
Saxifraga cotyledon
Tufted Saxifrage
Saxifraga caespitosa
Irish Saxifrage
Saxifraga rosacea
Starry Saxifrage
Saxifraga stellaris
Mossy Saxifrage
Saxifraga hypnoides
Alpine Snow Saxifrage
Saxifraga nivalis
Slender Snow Saxifrage
Saxifraga tenuis
Drooping Saxifrage
Saxifraga cernua
Alpine Brook Saxifrage
Saxifraga rivularis

Now we explore the Stonecrop family (Crassulaceae) in this section. On Iceland only a few stonecrop species are common in the wild. Typically the members of this family have fleshy leaves. It includes three stonecrops (Sedum) species and the rose root (Rhodiola rosea)
These are:

Roseroot
Rhodiola rosea
Biting Stonecropt
Sedum acre
Annual Stonecrop
Sedum an nuum
Hairy Stonecrop
Sedum-villosum


  Herbs, flowers with free petals (3): Rose, Buttercup & Poppy family


Now let's go to the Rose family (Rosaceae).
It is very difficult - if not impossible - to name a single feature for identifying a plant as a member of the rose family. Common species on Iceland are lady's-mantle's, Cinquefoils and Mountain&Water Avens. In order to keep some order I heve split them in three groups being:
1) the Alchemilla species (Lady's mantles)
2) the Potentils and relatives (Comarum and Sibaldia)
3) the remaining species
Whithin a specific species data page one can switch these lists

Common Lady's-mantle
Alchemilla vulgaris
Clustered Lady's-mantle
Alchemilla glomerulans
Hairy Lady's-mantle
Alchemilla filicaulis
Rock Lady's-mantle
Alchemilla wichurae
Faeroeic Lady's-mantle
Alchemilla faroensis
Alpine Lady's-mantle
Alchemilla alpina
Silver Weed
Potentilla anserina
Sea-sideSilverweed
Potentilla egedii
Alpine Cinquefoil
Potentilla crantzii
Marsh Cinquefoil
Comarum palustre
Creeping Sibbaldia
Sibbaldia procumbens
Mountain Avens
Dryas octopetala
Water Avens
Geum rivale
Stone Bramble
Rubus saxatilis
Wild Strawberry
Fragaria vesca
Meadowsweet
Filipendula ulmaria

The next family listed below is the Buttercup and Poppy family. Most of them have yellow flowers, some though have white flowers. Some are (semi-)aquatic plants. Buttercups on Iceland are usually yellow-flowered or white (be aware of cinquefoils of the Rose family with superficially similar flowers). A common but rather strange little plant is the alpine meadow-rue which has one row of small purple flower leaves. The link start with the alpine meadow-rue from where one can easily find and identify other buttercups. The poppy family is also included here.
In order to keep it apprehensible I have split this group into two differen lists, being:
1) The Yellow-flowered Buttercups
2) The White-flowering Buttercups and Poppies

Marsh-marigold
Caltha palustris
Meadow Buttercup
Ranunculus-acris
Creeping Spearwort
Ranunculus reptans
Pygmy Buttercup
Ranunculus pygmaeus
Arctic Buttercup
Ranunculus hyperboreus
Glacier Buttercup
Ranunculus glacialis
Thread-leaved
Water-crowfoot
Ranunculus trichophyllus
Alpine meadow-rue
Thalictrum alpinum
Arctic Poppy
Papaver radicatum
Iceland Poppy
Papaver croceum


  Herbs, flowers have free petals (4): the Willowherb family, the Carrot/Parsley & Ivy families and the Pea family


This section introduces the Willowherb family, the Umbel (Carrot/Parsley) & Ivy families and the Pea family. They are grouped in the following links:
Arctic riverbeauty
Chamerion latifolium
Rosebay Willowherb
Chamerion angustifolium
Chickweed Willowherb
Epilobium alsinifolium
Marsh Willowherb
Epilobium palustre
Alpine Willowherb
Epilobium anagallidifolium
Milky Willowherb
Epilobium lactiflorum
American Willowherb
Epilobium ciliatum
 Willowherb family (Onagraceae): a family of mainly bluish/purplish flowers. Typically willowherbs have flowers placed on top of a long stretched immature fruit. The fruits generally have more or less the same colour as the flowers (purplish). All more or less common species of this family consist of members of the Chamerion genus and the Epilobium species.
Garden Angelica
Angelica archangelica
Wild Angelica
Angelica sylvestris
Caraway
Carum carvi
Sweet Cicely
Myrrhis odoratum
Cow Parsley
Cow Parsley
Giant Hogweed
Heracleum mantegazzianum
 Carrot family (Apiaceae formerly known as Umbelliferae): Typically for this family is the combination of compound leaves and umbel shaped inflorescense's, hence the family name Umbelliferae.
Marsh Pennywort
Hydrocotyle vulgaris
 The Marsh Pennywort was until recently regarded as a member of the parsley family (Apiaceae) but is now a member of the Ivy family (Araliaceae).
Nootka lupin
Lupinus nootkatensis
Tufted vetch
Vicia cracca
White Clover
Trifolium repens
Red Clover
Trifolium pratense
Sea Pea
Lathyrus japonicus
Kidney Vetch
Anthyllis vulneraria
 Pea family (Fabaceae also known as Papillionaceae): The members of the Pea family have a unique flower structure and fruits (pod fruits). The flower petals consists of a usually large top petal two side petals and a boat shaped bottom petal in which lies a column of the stamens and pistil with the early pod fruit.

  Herbs, flowers have free petals (5): Mustard family


Members of the mustard family - known both as Cruciferae and Brassicaceae - are pure herbaceas plants. Many vegetables belong to this group: cabbages, radish, etc. On Iceland many species of the wild are small and white flowering plants. Because there are also many white-flowering members of the pink family on Iceland - here is the simple way to distinguish them: pink family species always have opposite leaves along their stems, members of the mustard family never have opposite leaves along their stems.
The Draba genus with white flowers is common with a few species. Next to other white-flowering species there are also a few non-white flowering species.

Examples of mustard family species 1&2: Non-white flowering species & White/yellow flowering species belonging to the Draba genus

Lady Smock
Cardamine nymanii
Hawkweed-leaved
Treaclemustard
Erysimum hieracifolium
Snow Whitlowgrass
Draba incana
Hoary Whitlowgrass
Draba nivalis
Rock Whitlowgrass
Draba norvegica
Alpine Whitlowgrass
Draba oxycarpa

aka Draba alpina

Examples of mustard family species 3: All other white flowering species

Alpine Rock-cress
Arabis alpina
Northern Rock-cress
Arabidopsis petraea
Common Whitlowgrass
Erophila verna
Common Scurvygrass
Cochlearia officinalis
Arctic Sea Rocket
Cakile arctica
Awlwort
Subularia aquatica

The mustard family has many representatives on Iceland. In order to simplify matters I have chosen to subdivide them in one list of non-white flowering species and two lists of white flowering species.

 Mustard family (Cruciferae) 1: non-white flowering species: The link opens with the Lady Smock from where you can cruise to other mustard family-members.

 Mustard family (Cruciferae) 2: white flowering species belonging to the Draba genus: The link opens with the Snow Whitlowgrass from where you can cruise to other Draba's as well as all other mustard family-members.

 Mustard family (Cruciferae) 3: white flowering species other than Draba species: The link opens with the Alpine Rock-cress from where you can cruise to other mustard family-members.



  Herbs, flowers have free petals (6): Pink family


Because the number of Pink species on Iceland is rather large, I have split the group in four series.

The first series includes the Chickweeds/Stitchwort group and Spurrey

Common Chickweed
Stellaria media
Lesser Stitchwort
Stellaria graminea
Fleshy Stitchwort
Stellaria crassifolia
Saltmarsh Stitchwort
Stellaria humifusa
Corn Spurrey
Spergula arvensis

The second series includes the Cerastium and Arenaria species (Mouse-ear and Sandworts):

Alpine Mouse-ear
Cerastium alpinum
Arctic Mouse-ear
Cerastium nigrescens
Starwort Mouse-ear
Cerastium cerastioides
Common Mouse-ear
Cerastium fontanum
Arctic Sandwort
Arenaria norvegica

The third series includes the Sagina species (Pearlwort species) and Minuartia(sandwort):

Knotted Pearlwort
Sagina nodosa
Alpine Pearlwort
Sagina saginoides
Procumbent Pearlwort
Sagina procumbens
Snow Pearlwort
Sagina nivalis
Heath Pearlwort
Sagina subulata
Northern Sandwort
Minuartia biflora

The fourth series includes the Lychnis (catchfly), Silene (campions) and Honckenya (Sea sandwort) species:

Alpine-catchfly
Lychnis alpina
Ragged Robin
Lychnis flos-cuculi
Moss Campion
Silene acaulis
Sea Campion
Silene uniflora
Red Campion
Silene dioica
Sea Sandwort
Honckenya peploides


  Herbs, flowers have free petals (7): Plantain family & related families (mare's tail, water-starworts and speedwell's)


First the three Plantain species

Sea Plantain
Plantago maritima
Greater Plantain
Plantago major
Ribwort Plantain
Plantago lanceolata

Second: related species (Hippuris and Callitriche species)

Mare's-tail
Hippuris vulgaris
Intermediate
Water-starwort
Callitriche hamulata
Vernal
Water-starwort
Callitriche palustris
Common
Water-starwort
Callitriche stagnalis

Third: related species (Veronica species)

Rock Speedwell
Veronica fructans
Alpine Speedwell
Veronica alpina
Heath Speedwell
Veronica officinalis
Marsh Speedwell
Veronica scutellata
Thyme-leaved Speedwell
Veronica serpyllifolia


  Herbs, flowers have free petals (8): Violets and miscellaneous other species with free petals


Wild Pansy
Viola tricolor
Alpine Marsh Violet
Viola palustris
introducing all viola's
Northern Marsh Violet
Viola epipsila
Heath Dog Violet
Viola canina

On Iceland four violet species are common. On the page of the Alpine Marsh Violet (V. palustris) the differences between the species are described. The link to this species is here.

Wood Crane's-bill
Geranium sylvaticum
Dwarf Cornel
Cornus suecica
Chickweed Wintergreen
Trientalis europaea
Fairy Flax
Linum catharticum

In this section we wrap up the remaining species with flowers having free petals. The species here are only distantly related.



  Flowers with fused petals 1: Gentian family


Gentians (family: Gentianaceae) are typically summer-flowering plants.

Alpine Gentian
Gentiana nivalis
Serrate Gentian
Gentianopsis dentosa
Marsh Felwort
Lomatogonium rotatum
Field gentian
Gentianella campestris
Northern Gentian
Gentianella aurea
Autumn Gentian
Gentianella amarella
Slender Gentian
Comastoma tenellum


  Flowers with fused petals 2: Broomrape and Mint family


The thumbnails below link to species of the broomrape family (Orobranchaceae) on Iceland.
Alpine Bartsia
Bartsia alpina
Cold Eyebright
Euphrasia frigida
Drug Eyebright
Euphrasia stricta
Red-tipped Lousewort
Pedicularis flammea
Yellow-rattle
Rhinanthus minor

These species are semi-parasites: they tap their own root system into the roots of other plants in order to acquire (steal) nutrients from these other plants (often grasses). They have flowers with a left/right symmetry.


The thumbnails below link to mint species (Lamiaceae) of Iceland
Wild Thyme
Thymus praecox
Selfheal
Prunella vulgaris
White Dead-nettle
Lamium album
Common Hemp-nettle
Galeopsis tetrahit
Water Mint
Mentha aquatica

The number of mint species growing in the wild on Iceland is small. Actually only thyme and selfheal are considered indigenous. The two "nettles" are introduced weeds and the water mint is rare introduced species only growing only on a few thermal soils. The low number of species reflects the fact that the members of the mint family are generally warmth-loving species. Having said this though it should be noted that the arctic thyme (a subspecies of the wild thyme) is very common all over Iceland where plant-growth conditions are not extremely tough. Members of this family also have flowers with a left/right symmetry.



  Flowers with fused petals 3: Daisy family


The daisy family (Asteraceae) is a very large family. Characteristic for this family is that (very) many single flowers are grouped together in a flowerhead which in turn resembles one single flower. This is accentuated by the fact that often the outer ring of the flowers on the head have one long petiole (ligulate or ray flowers). The ring of these single ray flowers on the outer edge of the flowerhead make the head appear to be just one flower (think of the sunflower). This is not always the case! There are daisies with only ray flowers (like dandelion) and there are those without ray flowers at all (example: Pineaple weed / Tansy).

The thumbnails below link to daisy (Asteraceae) species with yellow flowers (or at least with a yellow heart).
Hawkweed
Hieracium spp
Alpine Hawkweed
Hieracium alpinum
Icelandic Hawkweed
Pilosella islandica
Autumn Hawkbit
Leontodon autumnalis
Dandelion
Taraxacum spp
Sea Mayweed
Tripleurospermum
maritimum
Also known as
Matricaria maritima
Pineappleweed
Matricaria discoidea
Colt's-Foot
Tussilago farfara
Tansy
Tanacetum vulgare
Groundsel
Senecio vulgaris

The thumbnails below link to daisy (Asteraceae) species of the Achilea and Erigeron genera.
Yarrow
Achillea millefolium
Sneezewort
Achillea ptarmica
Alpine Fleabane
Erigeron borealis
Dwarf Fleabane
Erigeron uniflorus
Arctic Alpine Fleabane
Erigeron humilis

The thumbnails below link to cudweed/everlasting species of the daisy (Asteraceae) family.
Dwarf Cudweed
Omalotheca supina
Highland Cudweed
Omalotheca norvegica
Marsh Cudweed
Gnaphalium uliginosum

The thumbnails below link to thistle-like species and mugwort (Asteraceae) = daisy family.
Perennial Cornflower
Centaurea montana
Squarrose Knapweed
Centaurea triumfetti
Creeping Thistle
Cirsium arvense
Mugwort
Artemisia vulgaris


  Flowers with fused petals 4: All others


Bellflowers, Forget-me-not's and Oysterplant (Campanulaceae and Boraginaceae families):

Harebell
Campanula rotundifolia

also info on C. uniflora
Clustered Harebell
Campanula glomerata
Field Forget-me-not
Myosotis arvensis
Water Forget-me-not
Myosotis scorpioides
Oyster plant
Mertensia maritima

Bedstraw (Galium) species (Rubiaceae family).

For other
bedstraws
see:
Northern bedstraw
Northern bedstraw
Galium boreale
Slender bedstraw
Galium normanii
Lady's Bedstraw
Galium verum

Follows the remaining herbs with fused petals: Thrift, Common Butterwort, Valerian and Devil's-bit Scabious species.
Sealavender family (Plumbaginaceae), Bladderwort family (Lentibulariaceae) and Honeysuckle family (Caprifoliaceae)

Thrift
Armeria maritima
Common Butterwort
Pinguicula vulgaris
Hill Valerian
Valeriana officinalis
ssp sambucifolia
Devil's-bit Scabious
Succisa pratensis


  Monocotyledons: Lily groups including rushes
  Monocotyledons: Orchids
  Monocotyledons: Sedges
  Monocotyledons: Grasses
  Water plants


Lily family and closely related to the lily family members.

Herb Paris
Paris quadrifolia
Scottish asphodel
Tofieldia pusilla
Marsh Arrowgrass
Triglochin palustris

The number of species belonging to the Lily family or any closely related family growing in the wild on Iceland is very limited. Very common though is the Scottish asphodel (Tofieldia pusilla). Quite common too are Arrowgrasses (Marsh and Sea arrowgrasses). The Herb Paris (Paris quadrifolia) is more rare. It can be found in lava crevasses.


Rushes
Due to their leaf-forms, rushes appear at first glance to be something like grasses or sedges. Close inspection on flowers show they have - be it small - neat 6 floral leaves like lily flowers - very different to the complex spike(lets) inflorescences of sedges and grasses.


First: the Luzula rushes (known as Wood-rushes)
These rushes have grass blade-like leaves

Heath Wood-rush
Luzula multiflora
Sudetan Wood-rush
Luzula sudetica
Spiked Wood-rush
Luzula spicata
Curved Wood-rush
Luzula arcuata

Second: the Juncus rushes The Juncus rushes have hollow-pointed leaves (more or less like chives)
For conveniance I have split them in three groups: the taller species (20cm+), the middel-sized species (10 à 15 cm) and the smaller (low) species (rarely taller than 5 cm. be aware there are more of these than depicted below: just open any of them to get a lead to the others).

Taller species: over 20cm (usually 40cm+).

Arctic Rush
Juncus arcticus
subspecies: arcticus
>Arctic Rush
Juncus arcticus
subspecies: intermedius
Baltic Rush
Juncus balticus
Thread Rush
Juncus filiformis

Middle-sized species: 10 to 20 cm tall - (rarely up to 30cm)

Jointed Rush
Juncus articulatus
Alpine Rush
Juncus alpinoarticulatus
Chestnut Rush
Juncus castaneus

Smaller (low) species (rarely over 5cm. tall ; occasionally up to 25cm.)

Three-leaved Rush
Juncus trifidus
Three-flowered Rush
Juncus triglumis
Two-flowered Rush
Juncus biglumis
Frog Rush
Juncus ranarius =
Juncus ambiguus
Bulbous Rush
Juncus bulbosus

Note: there are more smaller rush species. To find them just link to any of the above and they appear in the left menu-list

Orchids:
Although the number of common species is relatively low, orchids are common throughout the better vegetated regions of Iceland. Below are listed all more or less common orchid species of Iceland (just open any species and this list will appear).

Frog Orchid
Dactylorhiza viride
Heath Spotted Orchid
Dactylorhiza maculata
ssp. intermedius
Northern Green Orchid
Platanthera hyperborea
Small-white orchid
Pseudorchis albida
Coralroot orchid
Corallorhiza trifida
Common Tayblade
Listera ovata
Lesser Tayblade
Listera cordata

On Iceland many sedge-species can be found. I have split them - quite arbitrarely - in three "Carex"groups (tall/middle-sized an small)and two non-Carex species: Eleocharis / Spike-Rush species and other/remaining species (including Eriophorum species).

Below the two tall "Carex" sedge species:

Bottle Sedge
Carex rostrata
Lyngbye's sedge
Carex lyngbyei

Next the middle-sized "Carex" sedge species:
first middle-sized "Carex" sedge species series

Common Sedge
Carex nigra
Stiff Sedge
Carex bigelowii
Krause's sedge
Carex krausei
White sedge
Carex curta

second middle-sized "Carex" sedge species series

Black Alpine-sedge
Carex atrata
Hare's-foot sedge
Carex lachenalii
Green Yellow-sedge
Carex demissa

Also introducing Carex flava
Large Yellow-sedge

third middle-sized "Carex" sedge species series

Sheathed Sedge
Carex vaginata
Mountain Bog-sedge
Carex rariflora
Tall Bog-sedge
Carex paupercula

Also introducing: Carex limosa
Common Bog-sedge

And now the low "Carex" sedge species:

Curved Sedge
Carex maritima
Close-headed Alpine-sedge
Carex norvegica
Dioecious Sedge
Carex dioica

And here some Spike-rush species (Eleocharis sp.)

Common Spike-rush
Eleocharis palustris
Slender Spike-rush
Eleocharis uniglumis
Few-flowered Spike-rush
Eleocharis quinqueflora

Finally the remaining sedges (including cottongrass species: Eriophorum sp.)

Common Cottongrass
Eriophorum angustifolium
Scheuchzer's cottongrass
Eriophorum scheuchzeri
Bellard's Kobresia
Kobresia myosuroides

Just like sedges there are so many grass species that I have split them in seperate groups for conveniance. The basic element of grass flowers is the spikelet. They can be either arranged in spikes or panicles. Having said this though, some grass inflorescences are technically panicles but resembles spikes.

First, a few Poa (Meadow-grass) species which are more or less common on Iceland. Meadow-grasses have loose panicles.

Smooth Meadow-grass
Poa pratensis
Glaucous Meadow-grass
Poa glauca
Wavy Meadow-grass
Poa flexuosa
Alpine Meadow-grass
Poa flexuosa
Rough Meadow-grass
Poa trivialis

Second, a few Agrostis (Bent) and Deschampsia (Hair-grass) species. These too are grasses producing loose panicles.

Creeping Bent
Agrostis stolonifera
Brown Bent
Agrostis vinealis
Tufted Hair-grass
Deschampsia cespitosa
Waivy Hair-grass
Deschampsia flexuosa

Third, the remaining common species with loose panicles (fort the time being just one species).

Whorl grass
Catabrosa aquatica

Fourth, grasses with panicles which are contracted to the main stem and/or lateral stems, sometimes resembling a spike.

Lyme-grass
Leymus-arenarius
Holy-grass
Hierochloe odorata
Reflexed Saltmarsh-grass
Puccinellia capillaris
Viviparous Sheep's-Fescue
Festuca vivipara
Arctic Fescue
Festuca richardsonii
Mat-grass
Nardus stricta

Fifth (and last), grasses with spikes or spike-like inflorescences.

Timothy
Phleum pratense
Alpine Cat's-tail
Phleum alpinum
Sweet Vernal-grass
Anthoxanthum odoratum
Three-flowered False Oat
Trisetum triflorum

The thumbnails below link to some water plants of Iceland. This section of the flora of Iceland is all but complete. Watch for updates in 2014 and 2015

Alternate Water-milfoil
Myriophyllum alterniflorum
Red Pondweed
Potamogeton alpinus
Various-leaved Pondweed
Potamogeton gramineus
Bur-reeds
Sparganium sp
Bogbean
Menyanthes trifoliata

Water plants can be from very different taxonomic groups.