A cnidocyte is an explosive cell containing one large secretory organelle called a cnidocyst that can deliver a sting to other organisms. The presence of this cell defines the phylum Cnidaria. Cnidae are used to capture prey and as a defense against predators. A cnidocyte fires a structure that contains a toxin within the cnidocyst; this is responsible for the stings delivered by a cnidarian.
Radiata or Radiates is a historical taxonomic rank that was used to classify animals with radially symmetric body plans. The term Radiata is no longer accepted, as it united several different groupings of animals that do not form a monophyletic group under current views of animal phylogeny. The similarities once offered in justification of the taxon, such as radial symmetry, are now taken to be the result of either incorrect evaluations by early researchers or convergent evolution, rather than an indication of a common ancestor. Because of this, the term is used mostly in a historical context.
The ParaHox gene cluster is an array of homeobox genes from the Gsx, Xlox (Pdx) and Cdx gene families.
Hox genes, a subset of homeobox genes, are a group of related genes that specify regions of the body plan of an embryo along the head-tail axis of animals. Hox proteins encode and specify the characteristics of 'position', ensuring that the correct structures form in the correct places of the body. For example, Hox genes in insects specify which appendages form on a segment, and Hox genes in vertebrates specify the types and shape of vertebrae that will form. In segmented animals, Hox proteins thus confer segmental or positional identity, but do not form the actual segments themselves.
Antennapedia is a Hox gene first discovered in Drosophila which controls the formation of legs during development. Loss-of-function mutations in the regulatory region of this gene result in the development of the second leg pair into ectopic antennae. By contrast gain-of-function alleles convert antennae into ectopic legs.
The starlet sea anemone is a species of small sea anemone in the family Edwardsiidae native to the east coast of the United States, with introduced populations along the coast of southeast England and the west coast of the United States. Populations have also been located in Nova Scotia, Canada. This sea anemone is found in the shallow brackish water of coastal lagoons and salt marshes where its slender column is usually buried in the mud and its tentacles exposed. Its genome has been sequenced and it is cultivated in the laboratory as a model organism, but the IUCN has listed it as being a "Vulnerable species" in the wild.
Thomas Alan Stephenson FRS was a British naturalist, and marine biologist, specialising in sea anemones.
The mir-10 microRNA precursor is a short non-coding RNA gene involved in gene regulation. It is part of an RNA gene family which contains mir-10, mir-51, mir-57, mir-99 and mir-100. mir-10, mir-99 and mir-100 have now been predicted or experimentally confirmed in a wide range of species. miR-51 and miR-57 have currently only been identified in the nematode Caenorhabditis elegans.
Aiptasia is a genus of a symbiotic cnidarian belonging to the class Anthozoa. Aiptasia is a widely distributed genus of temperate and tropical sea anemones of benthic lifestyle typically found living on mangrove roots and hard substrates. These anemones, as well as many other cnidarian species, often contain symbiotic dinoflagellate unicellular algae of the genus Symbiodinium living inside nutritive cells. The symbionts provide food mainly in the form of lipids and sugars produced from photosynthesis to the host while the hosts provides inorganic nutrients and a constant and protective environment to the algae. Species of Aiptasia are relatively weedy anemones able to withstand a relatively wide range of salinities and other water quality conditions. In the case of A. pallida and A. pulchella, their hardiness coupled with their ability to reproduce very quickly and out-compete other species in culture gives these anemones the status of pest from the perspective of coral reef aquarium hobbyists. These very characteristics make them easy to grow in the laboratory and thus they are extensively used as model organisms for scientific study. In this respect, Aiptasia have contributed a significant amount of knowledge regarding cnidarian biology, especially human understanding of cnidarian-algal symbioses, a biological phenomenon crucial to the survival of corals and coral reef ecosystems. The dependence of coral reefs on the health of the symbiosis is dramatically illustrated by the devastating effects experienced by corals due to the loss of algal symbionts in response to environmental stress, a phenomenon known as coral bleaching.
Marine invertebrates are the invertebrates that live in marine habitats. Invertebrate is a blanket term that includes all animals apart from the vertebrate members of the chordate phylum. Invertebrates lack a vertebral column, and some have evolved a shell or a hard exoskeleton. As on land and in the air, marine invertebrates have a large variety of body plans, and have been categorised into over 30 phyla. They make up most of the macroscopic life in the oceans.
Sea anemones are a group of predatory marine invertebrates constituting the order Actiniaria. Because of their colourful appearance, they are named after the Anemone, a terrestrial flowering plant. Sea anemones are classified in the phylum Cnidaria, class Anthozoa, subclass Hexacorallia. As cnidarians, sea anemones are related to corals, jellyfish, tube-dwelling anemones, and Hydra. Unlike jellyfish, sea anemones do not have a medusa stage in their life cycle.
Epiactis is a genus of sea anemones in the family Actiniidae. There are about nineteen recognised species and the type species is Epiactis prolifera.
Edwardsiidae is a family of sea anemones. Edwardsiids have long thin bodies and live buried in sediments or in holes or crevices in rock.
ParaHoxozoa is a clade of animals that consists of Bilateria, Placozoa, and Cnidaria. The relationship of this clade relative to the two other animal lineages Ctenophora and Porifera is debated. Some phylogenomic studies have presented evidence supporting Ctenophora as the sister to Parahoxozoa and Porifera as the sister group to the rest of animals. Some studies have presented evidence supporting Porifera as the sister to Parahoxozoa and Ctenophora as the sister group to the rest of animals.
Nematosomes are multicellular motile bodies found in the gastrovascular cavity of the model sea anemone Nematostella vectensis starlet sea anemone. First described by Stephenson in 1935, nematosomes are the defining apomorphy (synapomorphy) of the genus Nematostella but have received relatively little study. Nematosomes can be observed circulating through the body cavity and tentacle lumen of adult anemones, occasionally coming to rest on the gastrodermis. Nematosomes that are dislodged from rest return to circulation. The lifespan of a single nematosome has not been studied.
Anne Carla Ferguson-Smith is a mammalian developmental geneticist. She is the Arthur Balfour Professor of Genetics and Pro-Vice Chancellor for Research and International Partnerships at the University of Cambridge. Formerly head of the Department of Genetics at the University of Cambridge, she is a Fellow of Darwin College, Cambridge and serves as President of the Genetics Society.
Edwardsiella lineata, the lined anemone, is a species of sea anemone in the family Edwardsiidae. It is native to the northwestern Atlantic Ocean where it occurs in the subtidal zone.
Hurst Castle and Lymington River Estuary is a 1,077.3-hectare (2,662-acre) biological and geological Site of Special Scientific Interest near Lymington in Hampshire. It is a Nature Conservation Review site and two areas are Geological Conservation Review sites. Three areas are local nature reserves, Boldre Foreshore, Sturt Pond and Lymington and Keyhaven Marshes; the latter site is managed by the Hampshire and Isle of Wight Wildlife Trust. Part of it is North Solent National Nature Reserve. It is part of Solent and Southampton Water Ramsar site and Special Protection Area. Parts of it are in Solent Maritime and Solent and Isle of Wight Lagoons Special Areas of Conservation.
