Microlife: Stormwater ponds - Cyanobacteria around cattails

Jul 8-9, 2010
Video: wetland microlife 6 of 14 clips

This was from a stormwater pond with a rocky bottom and many submerged plants growing further out. In places along the shore there were stands of cattails, and at least the nearest were surrounded by thick floating mats, coloured greenish-black except some dry spots that were singed brown. The sample included a large piece and some plant fragments from underneath it.

Stormwater pond
Cyanobacteria mat

The walls of the container were shortly covered by countless tadpole snails. These were accompanied by some leeches, including one large snail leech, and many cyclopoids with or without eggs. There were also many roundworms and midge larvae with them and in the mat, where some of the latter were visible by rhythmic pulsing.

In both places there were also many large Stentor, apparently eaten by cyclopoids, and various spirotrichs such as Stylonychia. The mats themselves were mainly filamentous cyanobacteria, at least partly gliding or rotating types, and dropped innumerable small diatoms whenever disturbed.

A variety of rotifers were present including several bdelloids, Lepadella, Brachionus, and worm-like ploimids. Other notable animals included some flatworms, small annelids, and a sluggish Hydra. Finally, on the second day a silvery film had started to form on the mat, which contained several fast Paramecium and smaller ciliates.

↬ Thanks to zoologist Dr. Alexander Kostenko for confirming the identification of Stenostomum.

Kingdom Bacteria
…Phylum Cyanobacteria – blue-green algae

Cyanobacteria
Cyanobacteria - about 5 µm wide
Arthrospira
Arthrospira - about 5 µm wide
Cyanobacteria
Cyanobacteria - about 17, 6 µm wide

Kingdom Plantae
…Phylum Chlorophyta – green algae

Spirogyra
Spirogyra - about 50 µm wide
Closterium, euglenid
Closterium, Euglenida - about 570 µm, 90 µm
Closterium
Closterium - about 600 µm

Kingdom Chromista
…Phylum Ciliophora – ciliates

Spirostomum
Spirostomum - about 1.1 mm
Stentor
Stentor - front about 155 µm wide
Ciliate
Ciliophora - about 150 µm
Euplotes
Euplotes - about 45 µm
Spirotrich
Spirotrichea - about 170 µm
Spirotrich
Spirotrichea - about 120 µm
Spirotrich
Spirotrichea - about 100 µm
Spirotrich
Spirotrichea - about 120 µm
Stylonychia
Stylonychia - body about 105 µm
Ciliates
Ciliophora - about 65, 25 µm
Pleurostome
Pleurostomatida - about 130 µm
Phyllopharyngea
Phyllopharyngea - about 100 µm
Frontonia
Frontonia - about 105 µm
Paramecium
Paramecium - about 200 µm
Sessilid
Sessilida - about 45 µm
Vorticellid
Vorticellidae - body about 55 µm

…Phylum Ochrophyta – heterokont algae

Nitzschia
Nitzschia - about 275 µm
Gyrosigma
Gyrosigma - about 100 µm
Diatoms
Diatomeae - about 30-75 µm
Diatom
Diatomeae - about 100 µm
Diatom
Diatomeae - about 155 µm
Diatom
Diatomeae - about 100 µm
Diatom
Diatomeae - about 75 µm

Kingdom Protozoa
…Phylum Euglenozoa

Peranema
Peranema - about 65 µm
Euglenid
Euglenida - about 80 µm
Euglenid
Euglenida - about 95 µm

…Phylum Amoebozoa

Mayorella
Mayorella - about 70 µm
Tubulinea
Tubulinea - about 55 µm
Amoebid
Amoebidae - about 75 µm long and wide

Kingdom Animalia
…Phylum Cnidaria

Hydra
Hydra - body about 7.3 mm

…Phylum Gnathifera – rotifers & allies

Rotaria
Rotaria - about 490 µm
Bdelloid
Bdelloida - about 110 µm wide
Colurella
Colurella - about 110 µm
Lepadella
Lepadella - about 145 µm
Ploima
Ploima - about 370 µm
Ploima
Ploima - about 90 µm
Euchlanis
Euchlanis - body and foot about 400 µm
Lecane
Lecane - about 190 µm
Brachionus
Brachionus - body about 175 µm
Brachionus
Brachionus with egg - body about 220 µm

…Phylum Gastrotricha

Chaetonotid
Chaetonotidae - about 165 µm

…Phylum Platyhelminthes – flatworms

Stenostomum
Stenostomum - about 940 µm

…Phylum Annelida – segmented worms

Aeolosoma, Stylonychia
Aeolosoma, Stylonychia - about 1.8 mm, 150 µm
Chaetogaster
Chaetogaster - up to 90 µm wide
Oligochaete
Clitellata - about 210 µm wide
Ribbon leech
Erpobdellidae - about 8.8 mm
Snail leech
Glossiphoniidae - about 14.7 mm [composite]

…Phylum Mollusca

Tadpole snail
Physidae - shell about 1.4 mm
Tadpole snails
Physidae - shells about 3.1, 4.0 mm
Snail
Gastropoda - shell about 1.7 mm wide

…Phylum Nematoda – roundworms

Roundworm
Nematoda - about 530 µm

…Phylum Arthropoda – insects, crustaceans & allies

Podocopid
Podocopida - body about 160 µm
Cyclopoid with eggs
Cyclopoida with eggs - body about 870 µm
Cyclopoid devouring Stentor
Cyclopoida eating Stentor - about 330 µm wide
Copepod larva
Copepoda, larva - body about 125 µm
Copepod larva
Copepoda, larva - body about 275 µm
Amphipod
Amphipoda - about 2.3 mm
Amphipod
Amphipoda - about 7.3 mm
Daphnia ephippium
Daphnia, ephippium - main case about 600 µm
Midge larva
Chironomidae, larva - about 780 µm
Midge larva
Chironomidae, larva - about 6.8 mm