oceany: Mollusca

Evidence: 45 • authority: 72

Annelids (), also known as segmented worms, are animals that comprise the phylum Annelida (; from Latin anellus 'little ring'). The phylum contains over 22,000 extant species, including ragworms, earthworms, and leeches. The species exist in and have adapted to various ecologies – some in marine environments as distinct as tidal zones and hydrothermal vents, others in fresh water, and yet others in moist terrestrial environments. Annelids are bilaterally symmetrical, triploblastic, coelomate, invertebrate organisms. They also have parapodia for locomotion. Most textbooks still use the traditional division into Polychaetes (almost all marine), Oligochaetes (which include earthworms) and Hiru…

Evidence: 41 • authority: 88

Introduction to the Lophotrochozoa, and the Phylum Mollusca. This chapter provides an overview of the Lophotrochozoa and the phylum Mollusca. The Mollusca, Nemertea, Annelida, and the three lophophorate phyla comprise the clade Lophotrochozoa in the form of the so-called small shelly fossils. Molluscs comprise the second largest phylum of animals (after arthropods) and include some of the best-known invertebrates. The chapter then details the body plan and the very long and convoluted taxonomic history and classification of molluscs. Despite the enormous diversity, all molluscs share a suite of defining characteristics that include bilateral symmetry, reduced coelom, visceral mass, body cov…

Evidence: 41 • authority: 72

The Bryozoa (also known as the Polyzoa, Ectoprocta or commonly as moss animals) are a phylum of simple, aquatic invertebrate animals, nearly all living in sedentary colonies. Typically about 0.5 millimetres (1⁄64 in) long, they have a special feeding structure called a lophophore, a "crown" of tentacles used for filter feeding. The bryozoa are classified as the marine bryozoa (Stenolaemata), freshwater bryozoa (Phylactolaemata), and mostly-marine bryozoa (Gymnolaemata), a few members of which prefer brackish water. Most marine bryozoans live in tropical waters, but a few are found in oceanic trenches and polar waters. 5,869 living species of bryozoa are known. Originally all of the crown gr…

Evidence: 31 • authority: 72

Tunicates are marine invertebrates belonging to the subphylum Tunicata ( TEW-nih-KAY-tə). This grouping is part of the Chordata, a phylum which includes all animals with dorsal nerve cords and notochords (including vertebrates). The subphylum was at one time called Urochordata, and the term urochordates is still sometimes used for these animals. Despite their simple appearance and very different adult form, their close relationship to the vertebrates is certain. Both groups are chordates, as evidenced by the fact that during their mobile larval stage, tunicates possess a notochord, a hollow dorsal nerve cord, pharyngeal slits, post-anal tail, and an endostyle. They resemble a tadpole. Tunic…

Evidence: 31 • authority: 72

Marine life, which is also known as sea life or ocean life, refers to all the marine organisms that live in salt water habitats, or ecological communities that encompass all aquatic animals, plants, algae, fungi, protists, single-celled microorganisms and associated viruses living in the saline water of marine habitats, either the seawater of marginal seas and oceans, or the brackish water of coastal wetlands, lagoons, estuaries and inland seas. As of 2023, more than 242,000 marine species have been documented, and perhaps two million marine species are yet to be documented. On average, researchers describe about 2,300 new marine species each year. The study of marine life spans multiple fi…

Evidence: — • authority: 72

An echinoderm () is any animal of the phylum Echinodermata (), which includes starfish, brittle stars, sea urchins, sand dollars and sea cucumbers, as well as the sessile sea lilies or "stone lilies". While bilaterally symmetrical as larvae, as adults echinoderms are recognisable by their usually five-pointed radial symmetry (pentamerous symmetry), and are found on the sea bed at every ocean depth from the intertidal zone to the abyssal zone. The phylum contains about 7,600 living species, making it the second-largest group of deuterostomes after the chordates, as well as the largest marine-only phylum. The first definitive echinoderms appeared near the start of the Cambrian. Echinoderms ar…

Evidence: — • authority: 72

This article lists the largest organisms for various types of life and mostly considers extant species, which found on Earth can be determined according to various aspects of an organism's size, such as: mass, volume, area, length, height, or even genome size. Some organisms group together to form a superorganism (such as ants or bees), but such are not classed as single large organisms. The Great Barrier Reef is the world's largest structure composed of living entities, stretching 2,000 km (1,200 mi) but contains many organisms of many types of species. When considering singular entities, the largest organisms are clonal colonies which can spread over large areas. Pando, a clonal colony of…

Evidence: — • authority: 72

The list of marine molluscs of South Africa is a list of saltwater species that form a part of the molluscan fauna of South Africa. This list does not include the land or freshwater molluscs. Mollusca is a phylum of protostomic invertebrate animals, whose members are known as molluscs or mollusks (). 86,600 extant species of molluscs are recognized, making it the second-largest animal phylum after Arthropoda. The number of additional fossil species is estimated between 60,000 and 100,000, and the proportion of undescribed extant species is very high. Many taxa remain poorly studied. Molluscs are the largest marine phylum, comprising about 23% of all the named marine organisms. They are high…

Evidence: — • authority: 72

Marine invertebrates are invertebrate animals that live in marine habitats, and make up most of the macroscopic life in the oceans. It is a polyphyletic blanket term that contains all marine animals except the marine vertebrates, including the non-vertebrate members of the phylum Chordata such as lancelets, sea squirts and salps. As the name suggests, marine invertebrates lack any mineralized axial endoskeleton, i.e. the vertebral column, and some have evolved a rigid shell, test or exoskeleton for protection and/or locomotion, while others rely on internal fluid pressure to support their bodies. Marine invertebrates have a large variety of body plans, and have been categorized into over 30…

Evidence: — • authority: 92

Population-level transcriptomic datasets from two benthic invertebrates exposed to long-term experimental warming and acidification.. Ocean warming and acidification are major drivers of change in marine ecosystems, with particularly strong impacts on low-mobility benthic organisms. Despite their ecological importance, genomic and transcriptomic resources from sponges (Phylum, Porifera) and marine gastropods (Phylum, Mollusca) that capture responses to long-term, combined climate stressors and population-level variability remain limited. Herein, we present population-level RNA-seq datasets from the sponge Chondrilla nucula and the gastropod Hexaplex trunculus , collected from northern and s…

Evidence: — • authority: 72

Mollusca is a phylum of protostomic invertebrate animals, whose members are known as molluscs or mollusks (). 86,600 extant species of molluscs are recognized, making it the second-largest animal phylum after Arthropoda. The number of additional fossil species is estimated between 60,000 and 100,000, and the proportion of undescribed extant species is very high. Many taxa remain poorly studied. Molluscs are the largest marine phylum, comprising about 23% of all the named marine organisms. They are highly diverse, not just in size and anatomical structure, but also in behavior and habitat, as numerous groups are freshwater and even terrestrial species. The phylum is typically divided into 7…