CYSTOIDEA Meaning and
Definition
-
Cystoidea is a term used in paleontology to refer to a now extinct class of marine invertebrates that lived during the Paleozoic era, specifically from the Ordovician to the Silurian periods. These organisms were echinoderms, a group that includes modern sea urchins and starfish. Cystoidea, however, had a distinct morphology that differentiated them from other echinoderms.
Cystoidea were characterized by their spherical or oval-shaped bodies, which were covered in a rigid exoskeleton composed of small plates or ossicles. They possessed a unique feature called a theca, which was a protective casing that encased their body and was made up of these ossicles. The theca was divided into two symmetrical halves, allowing the animal to partially withdraw itself inside for protection. They also had a mouth and anus located on the upper surface of their body.
These ancient creatures were sessile, meaning they were attached to the ocean floor via a long stem or stalk called a column. The column held the cystoid body above the seabed, allowing them to filter feed on small particles suspended in the water. It is believed that Cystoidea had a simple water vascular system and possessed numerous branched appendages for capturing food.
Cystoidea, along with other primitive echinoderms, are considered important in understanding the early evolution and diversification of this phylum. Their fossil record provides significant insights into early marine ecosystems and evolutionary processes during the Paleozoic era. Today, Cystoidea are only known from their fossilized remains, found in various locations around the world.
Common Misspellings for CYSTOIDEA
Etymology of CYSTOIDEA
The word "Cystoidea" is derived from the Greek words "kystis", meaning "bladder", and "oida", meaning "resembling" or "like". The term was coined in the mid-19th century by the renowned British paleontologist Thomas Austin. It was used to describe a class of extinct echinoderms characterized by their sac-like or bladder-like bodies. These ancient marine creatures, commonly known as "cystoids", lived during the Paleozoic era and are considered distant relatives of modern-day starfish and sea urchins. The term "Cystoidea" was chosen due to the resemblance of their body structure to a bladder or sac-like shape.
Infographic
Add the infographic to your website:
