- Latin Name: Zygnematales
- Latin Family Name: Zygnemataceae and Spirogyra
- Common Name: Filamentous Green Algae
- Other Names: Conjugatales, conjugating green algae, water silk
Origin:
Likely originates from North America.
Biology:
Most members of both families live in freshwater, and form an important component of the algal scum that grows on or near plants and rocks. Almost all species of Zygnematales live in freshwater environments, where they are important as primary producers. They are commonly called "pondscum", and make up the filamentous periphyton in ponds, growing on and around the larger aquatic plants.
Identification:
Zygospore shape and wall structure are important features used in identifying species in the Zygnematales. Spirogyra is a common green algae found in shallow warm water where it can form extensive floating mats in both standing and flowing water. Lift the algae from the water to determine its silky quality; the filament mats feel very slimy to the touch, noticeably so when swimming or wading through them. The mats are capable of blocking stream channels and are visible as cloudy filaments just below the water’s surface. Colour is usually a vibrant green while the algae is in its spring growth stage. Once it reaches a reproductive stage, the colour can shift to a yellowish-brown.
Characteristics Important to Control:
Abundant growth in spring can result in clogged filters, seepage areas, drainage canals, and coves. Dense mats can deplete oxygen, interfere with fishing, or provide breeding sites for mosquitoes. The algae cannot maintain positive photosynthesis in high temperatures or low light. Herbicides may be used to suppress Spirogyra, but an algaecide will be necessary to control it.
