Phylum: Cnidaria (Jellyfish, Corals, Sea Anemones etc.)

"The phylum Cnidaria (pronounced “nih DARE ee uh”) includes soft-bodied stinging animals such as corals, sea anemones, and jellyfish. The phylum’s name is derived from the Greek root word cnid- meaning nettle, a stinging plant. Cnidarians are found in many aquatic environments. Sea anemones are widely distributed, from cold arctic waters to the equator, from shallow tide pools to the bottom of the deep ocean. Jellyfish float near the surface of the open oceans and in some tropical freshwater lakes. Corals are found primarily in shallow tropical waters, but a few grow in deep cold ocean waters. Small anemone-like cnidarians like Hydra sp. are also found in freshwater lakes and streams. Cnidarians range in size from tiny animals no bigger than a pinhead to graceful giants with trailing tentacles several meters long... The body plans cnidarians generally have [includes] radial symmetry. Because the tentacles of corals, jellyfish, and sea anemones have this radial structure, they can sting and capture food coming from any direction...

Many cnidarians take two main structural forms during their life cycles, a polyp form and a medusa form. The polyp form has a body shaped like a hollow cylinder or a bag that opens and closes at the top (Fig. 3.25 A). Tentacles form a ring around a small mouth at the top of the bag. The mouth leads to a central body cavity, the gastrovascular cavity (Fig. 3.24 B). Polyps attach to hard surfaces with their mouths up. Because they are sessile organisms, they can only capture food that touches their tentacles. Their mesoglea layer is very thin. Corals and sea anemones are polyps. Most of these animals are small, but a few sea anemones can grow as large as 1 meter in diameter. The second structural form that cnidarians have is called the medusa form. Medusa bodies are shaped like an umbrella with the mouth and tentacles hanging down in the water. The mouth leads upward into the gastrovascular cavity. Medusae (plural; the singular form is medusa) are not sessile, but rather are motile, meaning that they swim freely in the ocean. Their mesoglea is thick and makes up most of their bulk. Jellyfish are medusae. Medusae come in many sizes ranging from small 2.5-centimeter-long box jellies to the lion’s mane jellyfish, which has an umbrella over 2 m across. In many ways polyps and medusae are really the same basic body plan, except each is upside down compared to the other. Some cnidarians go through both a polyp and medusa phase in their life cycle. However, one or the other is the dominant phase in different species."

Read more: https://manoa.hawaii.edu/exploringourfluidearth/biological/invertebrates/phylum-cnidaria

Class: Anthozoa

Subclass: Hexacorallia

Order: Actiniaria

Family: Edwardsiidae

Order: Scleractinia

Family: Dendrophylliidae

Family: Montastraeidae

Family: Mussidae

Family: Oculinidae

–No subordinate taxa

Family: Pocilloporidae

Family: Rhizangiidae

Order: Zoantharia

Family: Neozoanthidae

Subclass: Octocorallia

Order: Alcyonacea

Family: Nidaliidae

Class: Cubozoa

Order: Carybdeida

Family: Alatinidae

Class: Hydrozoa

Subclass: Hydroidolina

Order: Anthoathecata

Family: Acaulidae

Family: Cladonematidae

Family: Corymorphidae

Family: Corynidae

Family: Milleporidae

Family: Pandeidae

Family: Ptilocodiidae

Family: Rathkeidae

Family: Rosalindidae

Family: Tubulariidae

Order: Leptothecata

Family: Aglaopheniidae

Family: Laodiceidae

Family: Lovenellidae

Family: Melicertidae

Family: Plumulariidae

Family: Tiaropsidae

Subclass: Trachylinae

Order: Limnomedusae

Family: Olindiidae

Order: Narcomedusae

Family: Cuninidae

Class: Myxozoa

Subclass: Myxosporea

Order: Bivalvulida

Family: Sphaerosporidae

Class: Scyphozoa

Subclass: Discomedusae

Order: Rhizostomeae

Family: Catostylidae

Appendix 1: Rediscovery turned out to be a new species

Galaxea paucisepta:

Claereboudt, M. (1990). Galaxea paucisepta nom. nov. (for G. pauciradiata), rediscovery and redescription of a poorly known scleractinian species (Oculinidae). Galaxea 9: 1-8.

Hoeksema, B. W. (1993). Some misapplied nomina nova in reef coral taxonomy (Scleractinia). Zoologische Mededelingen 67(3): 41-47.

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