Classification of Cnidarians

These flashcards cover the classification, characteristics, and reproduction methods of different classes of cnidarians including Hydrozoa, Scyphozoa, and Anthozoa.

Class Hydrozoa

Contains smaller jellyfish, including freshwater species like Hydra.

Hydra

Atypical freshwater polyp characterized by its polyp stage only.

Polymorphism

The occurrence of different forms, particularly in colonial hydrozoans.

Gastrozooid

Specialized polyp in colonial forms used for feeding.

Gonozoid

Specialized polyp for gamete production in colonial hydrozoans.

Dactylozoid

Defensive specialized polyp found in colonial hydrozoans.

Skeletozoid

Supportive specialized polyp in colonial forms.

Acellular Mesoglea

A gelatinous substance between the epidermis and gastrodermis in cnidarians.

Class Scyphozoa

Comprises large jellyfish, with medusoid forms being dominant.

Cubomedusae

Also known as 'Box Jellyfish', known for venom that can cause serious harm.

Cassiopeia

Commonly referred to as 'Upside-down jellyfish', known for its mutualistic relationship with green algae.

Scyphistoma

A stage in the life cycle of Scyphozoa, typically representing the polyp form.

Ephyra

Young medusa form in Scyphozoan life cycles.

Class Anthozoa

Includes only polypoid forms, such as corals and sea anemones.

Septa

Mesenteries in the gut of Anthozoans that partition the gastrovascular cavity.

Ahermatypic Corals

Soft corals such as octocorals, which do not build reefs.

Hermatypic Corals

Coral-forming species that have a symbiotic relationship with zooxanthellae.

Coral Bleaching

Occurs when corals expel their symbiotic algae, often due to stress.

Artificial Reefs

Constructed structures that promote marine life and serve as nurseries.

Planula

The free-swimming larval stage of cnidarians, resulting from fertilization.

Budding

A form of asexual reproduction where new individuals develop from polyps.