Dynamena
Dynamena is a genus of hydrozoans in the family Sertulariidae. They are colonial animals that form branching, feathery structures called hydroids. These hydroids are typically found attached to solid surfaces in marine environments, such as rocks, seaweed, and shells.
Common Names
Dynamena species are commonly known as "sea firs" due to their resemblance to the terrestrial tree.
Characteristics
Dynamena hydroids are characterized by their distinctive branching pattern and the presence of polyps, which are small, specialized structures responsible for feeding, defense, and reproduction. Each polyp is enclosed within a protective, cup-like structure called a theca. The polyps are arranged in a spiral pattern along the branches of the hydroid colony.
The polyps in Dynamena colonies are of two main types:
- Hydranths: These polyps are responsible for feeding. They have tentacles that capture small prey, such as plankton.
- Gonangia: These polyps are specialized for reproduction. They produce medusae, which are free-swimming, jellyfish-like forms.
Environments
Dynamena species are found in a variety of marine environments, including coastal waters, estuaries, and deeper ocean habitats. They are typically found in areas with moderate water currents and moderate salinity.
References
For more information on Dynamena, please refer to the following resources: