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How to interpret the results
Indicator taxa
Natural wetlands
Scroll to
Diatoms
Green algae
Diatoms
Achnanthidium
(Achnanthidiaceae)
Central raphe
Factsheet
Eunotia
and relatives (Eunotiaceae)
Rotational symmetry of cell face outline is 360 degrees; one end is a reflection of the other
Factsheet
Fragilaria
(Fragilariaceae)
Chloroplasts visible inside cells are brown
Factsheet
Gyrosigma
(Pleurosigmataceae)
Rotational symmetry of cell face outline 180 degrees, with the ends being opposite reflections of each other
Factsheet
Naviculoid diatoms (Naviculaceae)
Central raphe
Factsheet
Nitzschia
(Bacillariaceae)
Rotational symmetry of cell face outline 180 degrees, with the ends being opposite reflections of each other
Factsheet
Pinnularia
(Pinnulariaceae)
Central raphe
Factsheet
Ulnaria
(Fragilariaceae)
Raphe absent
Factsheet
Green algae
Chara
(Characeae)
Structured as a main axis with whorls of branches at nodes
Factsheet
Cladophora glomerata
(Cladophoraceae)
Filaments are one cell wide
Factsheet
Closterium
(Closteriaceae)
Cell outline crescent-shaped
Factsheet
Cosmarium
(Desmidiaceae)
Cell outline has a deep constriction
Factsheet
Desmidium
(Desmidiaceae)
Cells have constrictions between them
Factsheet
Euastrum
(Desmidiaceae)
Cell outline has a deep constriction
Factsheet
Hyalotheca
(Desmidiaceae)
Cells have constrictions between them
Factsheet
Micrasterias
(Desmidiaceae)
Cell outline has a deep constriction
Factsheet
Mougeotia
(Zygnemataceae)
Cell wall is smooth and featureless
Factsheet
Nitella
(Characeae)
Structured as a main axis with whorls of branches at nodes
Factsheet
Pleurotaenium
(Desmidiaceae)
Cell outline has a deep constriction
Factsheet
Spirogyra
(Zygnemataceae)
Cell wall is smooth and featureless
Factsheet
Spondylosium
(Desmidiaceae)
Cells have constrictions between them
Factsheet
Staurastrum
(Desmidiaceae)
Cell outline has a deep constriction
Factsheet
Staurodesmus
(Desmidiaceae)
Cell outline has a deep constriction
Factsheet
Xanthidium
(Desmidiaceae)
Cell outline has a deep constriction
Factsheet
Zygnema
(Zygnemataceae)
Cell wall is smooth and featureless
Factsheet
![[Achnanthidium], north Taranaki swamp, X400. Photo: Taranaki Regional Council & Manaaki Whenua](/assets/Tools-And-Resources/Identification/algae/achnanthidium400__FillMaxWzMwMCwyMDBd.jpg)
![[Eunotia sepentina], north Taranaki, X400. Photo: Taranaki Regional Council & Manaaki Whenua](/assets/Tools-And-Resources/Identification/algae/eunotia2__FillMaxWzMwMCwyMDBd.jpg)
![[Fragilaria], Waiorau tarn, X640 Photo: Otago Regional Council & Manaaki Whenua](/assets/Tools-And-Resources/Identification/algae/fragilaria640b__FillMaxWzMwMCwyMDBd.jpg)
![[Gyrosigma], Shag River, X400. Photo: Otago Regional Council & Manaaki Whenua](/assets/Tools-And-Resources/Identification/algae/gyrosigma640__FillMaxWzMwMCwyMDBd.jpg)
![[Nitzschia], Kaikorai tributary, X400. Photo: Otago Regional Council & Manaaki Whanua](/assets/Tools-And-Resources/Identification/algae/nitzschia2__FillMaxWzMwMCwyMDBd.jpg)
![[Pinnularia], Lake Tuakitoto, X640. Photo: Otago Regional Council & Manaaki Whenua](/assets/Tools-And-Resources/Identification/algae/pinnularia2__FillMaxWzMwMCwyMDBd.jpg)
![[Ulnaria], X320. Photo: Otago Regional Council & Manaaki Whenua](/assets/Tools-And-Resources/Identification/algae/ulnaria320b__FillMaxWzMwMCwyMDBd.jpg)
![[Chara] with oval oogonium, X6. Photo: Phil Novis, Manaaki Whenua](/assets/Tools-And-Resources/Identification/algae/chara_phil6__FillMaxWzMwMCwyMDBd.jpg)
![[Cladophora], Wairuna River, Otago. Photo: Otago Regional Council & Manaaki Whenua](/assets/Tools-And-Resources/Identification/algae/cladophora2__FillMaxWzMwMCwyMDBd.jpg)
![[Closterium], Lake Tuakitoto, X640 . Photo: Otago Regional Council & Manaaki Whenua](/assets/Tools-And-Resources/Identification/algae/closterium640__FillMaxWzMwMCwyMDBd.jpg)
![[Cosmarium], X400. Photo: Phil Novis, Manaaki Whenua](/assets/Tools-And-Resources/Identification/algae/cosmarium_phil400__FillMaxWzMwMCwyMDBd.jpg)
![[Desmidium], Duck Creek, Auckland, X50. Photo: Manaaki Whenua](/assets/Tools-And-Resources/Identification/algae/desmidium50b__FillMaxWzMwMCwyMDBd.jpg)
![[Euastrum], Ngaere wetland, X1000. Photo: Taranaki Regional Council & Manaaki Whenua](/assets/Tools-And-Resources/Identification/algae/euastrum1000__FillMaxWzMwMCwyMDBd.jpg)
![[Hyalotheca], Lake Tuakitoto, X640. Photo: Otago Regional Council & Manaaki Whenua](/assets/Tools-And-Resources/Identification/algae/hyalotheca640__FillMaxWzMwMCwyMDBd.jpg)
![[Micrasterias], north Taranaki swamp, X400. Photo: Taranaki Regional Council & Manaaki Whenua](/assets/Tools-And-Resources/Identification/freshwater-invertebrates/micrasterias400__FillMaxWzMwMCwyMDBd.jpg)
![[Mougeotia], Hayes Creek, X640. Photo: Otago Regional Council & Manaaki Whenua](/assets/Tools-And-Resources/Identification/algae/mougeotia640__FillMaxWzMwMCwyMDBd.jpg)
![[Nitella], X9. Photo: Otago Regional Council & Manaaki Whenua](/assets/Tools-And-Resources/Identification/algae/nitella9__FillMaxWzMwMCwyMDBd.jpg)
![[Pleurotaenium], north Taranaki swamp, X100. Photo: Taranaki Regional Council & Manaaki Whenua](/assets/Tools-And-Resources/Identification/algae/pleurotaenium100__FillMaxWzMwMCwyMDBd.jpg)
![[Spirogyra], X320. Photo: Otago Regional Council & Manaaki Whenua](/assets/Tools-And-Resources/Identification/algae/spirogyra320__FillMaxWzMwMCwyMDBd.jpg)
![[Spondylosium], X400. Photo: Taranaki Regional Council & Manaaki Whenua](/assets/Tools-And-Resources/Identification/algae/spondylosiumtrc__FillMaxWzMwMCwyMDBd.jpg)
![[Staurastrum], Lake Johnson, X640. Photo: Otago Regional Council & Manaaki Whenua](/assets/Tools-And-Resources/Identification/algae/staurastrum640__FillMaxWzMwMCwyMDBd.jpg)
![[Staurodesmus], Lake Rotoiti, X100. Photo: Thomas Wilding](/assets/Tools-And-Resources/Identification/algae/staurodesmus100__FillMaxWzMwMCwyMDBd.jpg)
![[Xanthidium], X400. Photo: Phil Novis, Manaaki Whenua](/assets/Tools-And-Resources/Identification/algae/xanthidium_phil__FillMaxWzMwMCwyMDBd.jpg)
![[Zygnema], X320. Photo: Otago Regional Council & Manaaki Whenua](/assets/Tools-And-Resources/Identification/algae/zygnema320__FillMaxWzMwMCwyMDBd.jpg)