Alphabetical list of algal images (no thumbnails, for fast loading), with brief descriptions.
[NB. IDs have been checked against "The Freshwater Algal Flora of the British Isles":
however some older IDs using "How to Know the Freshwater Algae" (Prescott) do not appear in FAFBI, and are marked "Prescott".]

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  Scenedesmus  1  2   3   4   5 6   7
coenobial Chlorophyte: up to 4 spindle-shaped cells clustered together Kindrogan
R. Yarrow
R. Ettrick
  Scenedesmus abundans 1   Loch Conailbhe
  Scenedesmus aculeolatus 1  2 3   Kilchiaran lochan
  Scenedesmus ?armatus v. bicaudatus  1   L. Gearach
  Scenedesmus communis  1  2 3  4   Kilchiaran lochan
Loch Conailbhe
  Scenedesmus dimorphus  1   2 3  4   culture
  Scenedesmus hystrix 1    Lismore
  Scenedesmus obliquus 1   R. Ettrick
   Scenedesmus obtusus 1   R. Ettrick
  Scenedesmus opoliensis 1   Lismore
  Scenedesmus ?opoliensis v. carinatus  1   L. Gearach
  Schizochlamydella  1   2   3   4   5  6   7 colonial Chlorophyte: spherical cells in a structureless mucilage sheath surrounded by semicircular mother cell-wall fragments. Kindrogan pond
Lochan an daimh
Lily Loch
  Scytonema  1   2 filamentous Cyanobacterium: sheathed, false branching not at heterocyst, sometimes two branches emerging at the same point
  Selenastrum capricornutum 1  2 Crescent-shaped unicellular chlorophyte: the capricornutum means 'like a goat's horns '. This is its old name -it is now Pseudokirchneriella subcapitata. It is widely used in toxicity testing. Culture
  ?Sellaphora laevissima  1  2  3 unicellular Diatom: Bemersyde
  Sirogonium   1  2  3  4 filamentous Chlorophyte, related to and similar to Spirogyra, but parallel, ribbon-like chloroplasts form less than half a complete twist round the circumference. Ard catchment
  Snowella  1   2  3  4 colonial Cyanobacterium: oval cells in spherical mucilage forming a layer some distance from outside, at the end of branched stalks. Loch Gorm
  Sorastrum   1   2   3
colonial chlorophyte (coenobium): cells linked by mucilage stalks to centre of spherical colony; cells with short spines. Loch Tallant
  Sphaerobotrys fluviatilis 1   2     colonial Chlorophyte: grows attached; cells somewhat pear-shaped, arranged in rows. Shewington
  Sphaerocystis sp.
1   2  3  4  5  6  7  8  9  10  11

colonial Chlorophyte (coenobium): spherical cells regularly arranged in a colonial mucilage sheath, without pseudocilia; reproduce by autospores which may remain in mother cell wall for a time. See also Coenochloris.
Images 7,8 & 9 show the effect of increasing exposure to Lugol's Iodine.

Millport Resr.
  ?Sphaerocystis planctonica   1   2   3 Showing spherical clusters of (?)autospores (approx. 3µm diameter) within a mucilage sheath. greenhouse
  Sphaerozosma  1 filamentous Desmid: each cell with a deep median incision and semicells a flattened ellipse; linked by terminal extensions to form long filaments, sometimes with a mucilage sheath. (There are similar related genera, eg, , eg, Spondylosium). Loch an Eilein
  The genus Spirogyra , with descriptive notes filamentous Chlorophyte: non-branching, long-cylindric cells with spiral band chloroplasts. Feels very smooth, hence common name 'Pond Silk'.  
  Spirogyra 11Ám.  1   Ardnave Loch
  Spirogyra 15 Ám.  1 Single cell: contrast shape with Spirotaenia Camphill Resr.
  Spirogyra 17Ám.  1   SCO067
  Spirogyra 20Ám. 1   2   Islay
  Spirogyra 22µm. 1   R. Yarrow
  Spirogyra 28Ám.  1   SCO067
Loch an Eilein
  Spirogyra 38Ám  1   Shewington
  Spirotaenia  1   2  3  4 unicellular Chlorophyte (Placoderm desmid) : cylindrical cell with rounded ends and spiral band chloroplast Lochan an daimh
Loch Trool
  Spondylosium sp.  1 filamentous Desmid: each cell with a deep median incision and semicells a flattened ellipse (similar to some Cosmarium); linked to form long filaments, sometimes with a mucilage sheath. (There are similar related genera eg. Sphaerozosma). L. Skeen

Spondylosium planum
1  2   3

L. Gorm
L. Chon
Loch an Eilein
  Staurastrum unicellular Desmid: semicells without marginal incisions or spines, but have many small processes and arms tipped with spines (2 or more arms per semicell)  
  Staurastrum anatinum  1 2 3   Green Lochan
L. Skeen
L. Chon
  Staurastrum arctiscon  1 2 3 4   SCO366
L. Chon
  Staurastrum armigerum fo. furcigerum
1 2  3   4 5  6  7
  L. Tallant
L. Kinnabus
L. Chon
Loch an Eilein
R. Yarrow
  Staurastrum asperum 1   L. Conailbhe
  Staurastrum avicula   1 2  3  ?4 5   L. Gorm
Loch an Eilein
R. Yarrow
  Staurastrum bieneanum 1 2 3   L. Chon
  Staurastrum ?cerastes   1 2 3 4 5 6   L. Chon
  Staurastrum chaetoceras 1  2   Millport 
  Staurastrum cingulum 1 2  3  4   L. Chon
Loch an Eilein
  Staurastrum ?cingulum v. obesum  1  2   R. Creran
  Staurastrum crenulatum  1   R. Yarrow
  Staurastrum ?cyrtocerum  1  2   R. Yarrow
  Staurastrum ?dilatatum  1   R. Creran
  Staurastrum ?furcatum 1  2   L. Gearach
  Staurastrum gracile 1  2  3     L. Gorm
L. Dhomhnuill
  Staurastrum ?hirsutum   1   2  3   L. Skeen
Camphill Resr.
  Staurastrum ?hirsutum v. muricatum 1    Camphill Resr
  Staurastrum inflexum   1    L. Conailbhe
  Staurastrum johnsonii   1 2   SCO140
  Staurastum longispinum   1 2   L. Chon
  Staurastrum lunatum 1 2  3  4   5  6   7   8  9   Green Lochan
L. Skeen
Ardnave Loch
lower L. Glenastle
Camphill Resr.
L. Gearach
  Staurastrum manfeldtii 1   Ardnave Loch
  Staurastrum ophiura  1 2 3 4 5     L. Chon
  Staurastrum pingue  ?1   R. Yarrow
  Staurastrum planctonicum 1 2   Millport
Ardnave Loch
  Staurastrum polytrichum   1  2  3   L. Chon
  Staurastrum proboscideum 1 2   L. Conailbhe
  Staurastrum pseudopelagicum  1 2   Ardnave Loch
lower L. Glenastle
  Staurastrum punctatulum  1   Ettrick Water
  Staurastrum sexangulare 1   Loch an Eilein
  Staurastrum teliferum  1 ?2 3 4 
L. Tallant
L. Conailbhe
Lochan an Daimh
  Staurodesmus unicellular Desmid: semicells have a smooth appearance, with spines marginal, or at the angles.  
  Staurodesmus aversus  1   Loch Dhomhnuill
  Staurodesmus convergens 1 2  3   Loch Dhomhnuill
L. Gearach
  Staurodesmus cuspidatus  1  2  3   L. Gorm
L. Conailbhe
L. Gearach
  Staurodesmus dejectus  1  2    L. Gorm
L. Tallant
  S. dejectus fo. apiculatus   1  2   3   Ardnave L.
Loch Dhomhnuill
  Staurodesmus ?extensus  1  2   L. Chon
R. Creran
  Staurodesmus ?indentatus  1   L. Gearach
  Staurodesmus mamillatus  1   2   3     L. Gorm
Ardnave L.
  Staurodesmus ?megacanthus 1  2   R. Creran 
  Staurodesmus subtriangularis   1   2   3 4  5     L. Chon
Loch an Eilein
R. Creran
  Staurodesmus triangularis  1   2   3   Green Lochan
L. Uigedail
  Stauroneis legumen  1 unicellular Diatom: cell longer than broad, 2 chloroplasts against the girdles. S.legumen is 'bean-shaped' Shewington
  ?Staurosirella 1 unicellular Diatom: Bemersyde
  Stenopterobia sigmatella  1  2   3  4 unicellular Diatom: sigmoid, narrow Lower L. Glenastle
Loch an Eilein
Loch Trool
R. Creran
  Stephanodiscus minutulus 1 unicellular centric Diatom Bemersyde

The genus Stigeoclonium, with descriptive notes


filamentous Chlorophyte: branched, ends of branches pointed or drawn out into long hairs; grows attached by a prostrate basal system of filaments (usually not collected when sampling) which is important in identifying species. Chloroplast a parietal plate; no colonial mucilage. Cf. Draparnaldia and Chaetophora  
  Group of Stigeoclonium  species   Shewington
  Stigeoclonium sp. 1   2   3   4   5   6  7   8  9  10 11  12  13  14  15  16   Ard catchment
Hidden Lochan
  Stigeoclonium ?amoenum   1  2  3   R. Yarrow
  Stigeoclonium farctum  1   2   3   Shewington
  Stigeoclonium helveticum  1 2  3  4  5   Shewington
  Stigeoclonium tenue 1 2   Shewington
  Stigonema 1 2 3 branched filamentous Cyanobacterium: cells spheroidal in a dense mucilaginous sheath, uniseriate in younger branches becoming multiseriate with branches starting as small protuberances growing out at right angles, plant a dark brown or green colour. Islay
  Stylosphaeridium  1   2  3 unicellular chlorophyte: epiphytic on other algae esp. cyanobacteria, attached by means of a stalk Millport
  Surirella angusta  1 unicellular Diatom: fairly large cells with prominent marginal costae SCO379
  Surirella capronii  1  2  3  4  5  Bemersyde
  Surirella elegans  1  2 SCO067
R. Creran
  Synechococcus 1 2  
Cyanophyte: solitary, or a pair of cells following cell division, blue-green colour without a mucilage sheath L. Tallant
  Synechococcus aeruginosus ?  1   L. Gorm
  Synechocystis   1   Cyanophyte: solitary or a pair of cells followiing cell division, blue-green colour with a mucilage sheath. L. Tallant
  Synedra acus 1   2 (both in valve view) unicellular Diatom: long, narrow cells with 2 chloroplasts against the girdles L. Ruime
Douglas Water
  Synedra berolinensis  1  2   2   Millport
R. Yarrow
  Synedra ulna  1 (girdle view)   2   Douglas Water
R. Yarrow
  Synura sp.  1   colonial Chrysophyte: oval cells with 2 brown chloroplasts and 2 flagella. Shewington



John Kinross