IDs have been checked against "The Freshwater Algal Flora of the British Isles" (FAFBI). Some older IDs done using "How to Know the Freshwater Algae" (Prescott).
Question marks (?) added where ID is uncertain.
| Name | Image Links | Description |
|---|---|---|
| Tabellaria fenestrata var. asterionelloides | 1 2 3 4 | Diatom: colonial/filamentous, attached to each other by mucilage pads at the corners to give stellate or zig-zag colonies; valves linear, sometimes inflated in the centre, but cell usually seen in girdle view, square or rectangular with obvious septa (long ribs extending up to half way across the cell) |
| Tabellaria fenestrata var. fenestrata | 1 | |
| Tabellaria flocculosa | 1 2 3 | |
| Tabellaria quadriseptata | 1 2 | |
| Teilingia granulata | 1 2 3 4 5 | Filamentous "Saccoderm" desmid, consisting of small, cosmarium-like cells linked by 2 button-like protrusions |
| Tetmemorus brebissonii | 1 | Desmid |
| Tetmemorus granulatus | 1 | |
| Tetracyclus lacustris | 1 | chain-forming Diatom |
| Tetraedriella polychloris | 1 | Xanthophyte |
| Tetraedron caudatum | 1 | unicellular Chlorophyte, 5-sided, deeply indented; with marginal processes armed with spines |
| Tetraedron incus | 1 2 3 | unicellular Chlorophyte, 4-sided, corners drawn out and ending in spines |
| Tetraedron minimum | 1 2 3 | unicellular Chlorophyte, 4-sided, marginal processes armed with 1-5 teeth |
| Tetraspora | 1 2 | colonial Chlorophyte: spherical cells in a gelatinous sac, with pseudocilia extending through the sac |
| Tetraspora gelatinosa | 1 2 3 4 | cells in 4's or 2's. Pseudocilia not visible in these images |
| Tolypothrix | 1 2 3 | filamentous Cyanobacterium: trichome not tapering, cells in a thich sheath (often brown), showing false branching with a heterocyst at the base of the branch |
| Tolypothrix distorta | 1 | |
| Tolypothrix distorta v. penicillata | 1 2 | |
| Tortitaenia luetkemuelleri | 1 2 | "Saccoderm" desmid, cylindrical tapering at both ends (spindle-shaped). Chloroplast with spiral ridges (cf. Spirotaenia which has a spiral chloroplast) |
| Trachelomonas | 1 | unicellular flagellate with a flask-shaped lorica |
| Tribonema | 1 2 3 4 5 | filamentous Xanthophyte: cells usually slightly swollen in the centre, with walls consisting of H-pieces (cf. Microspora), multiple disc chloroplasts. |
| Name | Image Links | Description |
|---|---|---|
| Ulothrix | Descriptive notes | filamentous Chlorophyte: unbranched, attached by holdfast cell (cells near holdfast usually narrower than those further along), single parietal band chloroplast complete or incomplete, occupying 80% or more of the cell surface; no mucilage |
| Ulothrix 11µm. | 1 2 | |
| Ulothrix 14µm. | 1 | |
| Ulothrix 14µm. sporulating | 1 | |
| Ulothrix 32µm. | 1 2 3 | |
| Ulothrix 48µm. | 1 | |
| Ulothrix 70µm. | 1 2 3 | |
| Uronema | 1 2 3 | filamentous Chlorophyte: unbranched, attached by holdfast disc, terminal cell swollen / pointed; chloroplast Ulotrichoid. |
| Name | Image Links | Description |
|---|---|---|
| Vaucheria | 1 2 3 4 5 | Branched filamentous Xanthophyte, filament a coenocytic tube (no individual cells), with numerous small chloroplasts, and specialised structures for sexual reproduction. Grows subaerially forming a felty mass on damp surfaces (river banks, etc.) |
| Volvox | 1 2 3 4 5 6 | Colonial Chlorophyte; flagellate cells forming a hollow spherical colony with cells spaced out from each other |
| Name | Image Links | Description |
|---|---|---|
| Wolozynskia tylota | 1 2 | flagellate Pyrrophyte |
| Woronichinia | 1 2 3 4 5 6 7 8 9 10 11 12 | colonial Cyanobacterium: oval cells in spherical mucilage; concentrated in outer layer, each with a stalk (just visible in images 2 and 3). Hard to distinguish from Coelosphaerium if stalks can't be seen. (10: showing stalks; 11: cells squeezed out under pressure) |
| Name | Image Links | Description |
|---|---|---|
| Xanthidium | 1 2 | unicellular Desmid: semicells dorsoventrally flattened without lateral incisions, with marginal spines and a central process |
| Xanthidium antilopaeum | 1 2 | |
| Xanthidium antilopaeum v. depauperatum | 1 2 3 4 | |
| Xanthidium antilopaeum v. hebridarum | 1 2 3 4 | |
| Xanthidium armatum | 1 | |
| Xanthidium cristatum | 1 2 3 4 | |
| Xanthidium octocorne | 1 | |
| Xanthidium subhastiferum | 1 |
| Name | Image Links | Description |
|---|---|---|
| Zygnema | 1 2 3 4 | filamentous Chlorophyte: unbranched; cylindrical cells with 2 stellate chloroplasts; undergoes conjugation - without finding zygospores it is not possible to distinguish species, also possibility of confusion with Zygnemopsis (and Zygogonium). |
| Zygnema 20µm. | 1 2 3 4 | |
| Zygnemopsis desmidioides | 1 2 | filamentous Chlorophyte: unbranched, cells long-cylindric with rounded ends, axile plate chloroplast, 2 pyrenoids. Other species of Zygnemopsis are indistinguishable from Zygnema except for their zygospores |
| Zygogonium | Description | filamentous Chlorophyte: unbranched. At first glance it may appear like Microspora, as the cells can look bulbous or barrel-shaped, and the ends of filaments appear H-shaped but the filament does not break up to release H-pieces and there are 1 or 2 stellate chloroplasts; the cell wall can be thick and chloroplast shape hard to see |
| Z. ericetorum | 1 2 3 4 5 6 7 8 9 10 11 12 13 |