Sertularella crassicaulis

Sertularella crassicaulis is a species of colonial hydroid belonging to the family Sertularellidae. These hydroids are characterized by their intricate, branching structures that form colonies. These colonies are composed of individual polyps, each specialized for a specific function, such as feeding, defense, or reproduction.

Description & Characteristics

Sertularella crassicaulis is a small, delicate hydroid with a distinctive branching pattern. The colonies typically reach a maximum size of a few centimeters. Each branch of the colony is composed of a series of interconnected polyps. The polyps are small and have a distinct, cup-shaped structure known as a hydrotheca. These hydrothecae are used to house the feeding polyps, known as hydranths, which have tentacles used for capturing prey.

Habitat and Occurrence

Sertularella crassicaulis is a marine hydroid that is widely distributed in the northern hemisphere. It is typically found in shallow waters, from the intertidal zone to depths of around 50 meters. It is commonly found in areas with moderate wave action and relatively high salinity. These hydroids are primarily associated with rocky shores and seaweeds, where they attach themselves using a specialized structure known as a hydrorhiza.

Taxonomy

Sertularella crassicaulis belongs to the Class: Hydrozoa, Order: Leptothecata, and Family: Sertularellidae. The Hydrozoa class encompasses a wide range of marine invertebrates, including hydroids, jellyfish, and siphonophores. Within the Hydrozoa, the Leptothecata order consists of colonial hydroids, such as Sertularella crassicaulis, that are characterized by their distinctive, branching structures. The Sertularellidae family is a diverse group of hydroids that includes many species found in a variety of marine habitats.

Feeding

Sertularella crassicaulis is a carnivorous hydroid that feeds on small planktonic organisms, such as copepods and larvae. The feeding polyps, or hydranths, extend their tentacles into the water column to capture prey. These tentacles are covered in stinging cells, known as nematocysts, that paralyze the prey. Once captured, the prey is transported to the mouth of the hydranth, where it is consumed.