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Pycnogonum Stearnsi
''Pycnogonum stearnsi'', commonly known as Stearns' sea spider, is a marine arthropod in the family Pycnogonidae. It is found on the western seaboard of North America. Description ''Pycnogonum stearnsi'' grows to about 2.5 cm (1 in) in length. It has a head with a large proboscis and a segmented body. It does not have the chelicerae or pedipalps typical of sea spiders but uses its barrel-shaped proboscis for feeding. It has no eyes or spiny processes. It has four pairs of stout walking legs tipped by claws and the male has a short additional pair of legs at the front for carrying the eggs. Its colour is plain white or cream, sometimes tinged pinkish or buff.''Pycnogonum stearnsi'' - Ives, 1883 WallaWalla. Retrieved 2011- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arthropod
Arthropods (, (gen. ποδός)) are invertebrate animals with an exoskeleton, a Segmentation (biology), segmented body, and paired jointed appendages. Arthropods form the phylum Arthropoda. They are distinguished by their jointed limbs and Arthropod cuticle, cuticle made of chitin, often Mineralization (biology), mineralised with calcium carbonate. The arthropod body plan consists of segments, each with a pair of appendages. Arthropods are bilaterally symmetrical and their body possesses an exoskeleton, external skeleton. In order to keep growing, they must go through stages of moulting, a process by which they shed their exoskeleton to reveal a new one. Some species have wings. They are an extremely diverse group, with up to 10 million species. The haemocoel, an arthropod's internal cavity, through which its haemolymph – analogue of blood – circulates, accommodates its interior Organ (anatomy), organs; it has an open circulatory system. Like their exteriors, the internal or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anthopleura Xanthogrammica
''Anthopleura xanthogrammica'', or the giant green anemone, is a species of intertidal sea anemone of the family Actiniidae. Other common names for this anemone include green surf anemone, giant green sea anemone, green anemone, giant tidepool anemone, anemone, and rough anemone. Description The column width and height can reach a maximum of 17.5 and 30 cm, respectively. The crown of tentacles can be as wide as 25 cm in diameter, while the column, itself, tends to be widest at the base in order to offer a more stable connection to the rocks. It has a broad, flat oral disk surface and no striping, banding, or other markings. Coloration If ''A. xanthogrammica'' is exposed to proper amounts of sunlight, it can appear bright green when submerged under water. When not submerged, it appears dark green or brown. This is because the anemone tends to close up and "droop" and its now exposed column is actually dark green and slightly brown, but the hidden tentacles and ora ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Larva
A larva (; plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle. The larva's appearance is generally very different from the adult form (''e.g.'' caterpillars and butterflies) including different unique structures and organs that do not occur in the adult form. Their diet may also be considerably different. Larvae are frequently adapted to different environments than adults. For example, some larvae such as tadpoles live almost exclusively in aquatic environments, but can live outside water as adult frogs. By living in a distinct environment, larvae may be given shelter from predators and reduce competition for resources with the adult population. Animals in the larval stage will consume food to fuel their transition into the adult form. In some organisms like polychaetes and barnacles, adults are immobil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gonopore
A gonopore, sometimes called a gonadopore, is a genital pore in many invertebrates. Hexapods, including insects have a single common gonopore, except mayflies, which have a pair of gonopores. More specifically, in the unmodified female it is the opening of the common oviduct, and in the male, it is the opening of the ejaculatory duct. The position of the gonopore varies considerably between groups, but is generally constant within groups, allowing its position to be used as a "segmental marker". In Malacostraca, it is on the sixth thoracic segment; in Symphyla it is on the fourth trunk segment; in arachnids, it is on the second segment of the opisthosoma. In insects and centipedes, the gonopores are close to the animal's tail, while in millipedes they are on the third body segment behind the head, near the second pair of legs. See also * Gonopod * Gonopodium Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Egg (biology)
An egg is an organic vessel grown by an animal to carry a possibly fertilized egg cell (a zygote) and to incubate from it an embryo within the egg until the embryo has become an animal fetus that can survive on its own, at which point the animal hatches. Most arthropods such as insects, vertebrates (excluding live-bearing mammals), and mollusks lay eggs, although some, such as scorpions, do not. Reptile eggs, bird eggs, and monotreme eggs are laid out of water and are surrounded by a protective shell, either flexible or inflexible. Eggs laid on land or in nests are usually kept within a warm and favorable temperature range while the embryo grows. When the embryo is adequately developed it hatches, i.e., breaks out of the egg's shell. Some embryos have a temporary egg tooth they use to crack, pip, or break the eggshell or covering. The largest recorded egg is from a whale shark and was in size. Whale shark eggs typically hatch within the mother. At and up to , the o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clavelina
''Clavelina'' ("little bottle") is genus of sea squirts (the Ascidiacea), containing the following species: *'' Clavelina amplexa'' Kott, 2002 *'' Clavelina arafurensis'' Tokioka, 1952 *'' Clavelina auracea'' Monniot, 1997 *'' Clavelina australis'' (Herdman, 1899) *'' Clavelina baudinensis'' Kott, 1957 *'' Clavelina borealis'' Savigny, 1816 *'' Clavelina brasiliensis'' (Millar, 1977) *'' Clavelina breve'' Monniot, 1997 *''Clavelina coerulea'' Oka, 1934 *'' Clavelina concrescens'' Hartmeyer, 1924 *'' Clavelina cyclus'' Tokioka & Nishikawa, 1975 *'' Clavelina cylindrica'' (Quoy & Gaimard, 1834) *''Clavelina dagysa'' (Kott, 1957) *''Clavelina dellavallei'' (Zirpolo, 1825) *''Clavelina detorta'' (Sluiter, 1904) *''Clavelina elegans'' (Oka, 1927) *''Clavelina enormis'' Herdman, 1880 *''Clavelina fasciculata'' Van Name, 1945 *''Clavelina fecunda'' (Sluiter, 1904) *''Clavelina gemmae'' Turon, 2005 *''Clavelina huntsmani'' Van Name, 1931 *''Clavelina kottae'' (Millar, 1960) *'' Clavelina ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ascidian
Ascidiacea, commonly known as the ascidians, tunicates (in part), and sea squirts (in part), is a polyphyletic class in the subphylum Tunicata of sac-like marine invertebrate filter feeders. Ascidians are characterized by a tough outer "tunic" made of a polysaccharide. Ascidians are found all over the world, usually in shallow water with salinities over 2.5%. While members of the Thaliacea and Larvacea (Appendicularia) swim freely like plankton, sea squirts are sessile animals after their larval phase: they then remain firmly attached to their substratum, such as rocks and shells. There are 2,300 species of ascidians and three main types: solitary ascidians, social ascidians that form clumped communities by attaching at their bases, and compound ascidians that consist of many small individuals (each individual is called a zooid) forming colonies up to several meters in diameter. Sea squirts feed by taking in water through a tube, the oral siphon. The water enters the mouth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aglaophenia
''Aglaophenia'' is a genus of hydrozoans in the family Aglaopheniidae. Species The following species are classed in this genus: * '' Aglaophenia acacia'' Allman, 1883 * '' Aglaophenia acanthocarpa'' Allman, 1876 * '' Aglaophenia amoyensis'' Hargitt, 1927 * '' Aglaophenia baggins'' Soto Àngel & Peña Cantero, 2017 * '' Aglaophenia bakeri'' Bale, 1919 * '' Aglaophenia bicornuta'' Nutting, 1900 * '' Aglaophenia billardi'' Bale, 1914 * '' Aglaophenia bilobidentata'' Stechow, 1908 * '' Aglaophenia brachiata'' (Lamarck, 1816) * '' Aglaophenia calamus'' Allman, 1883 * '' Aglaophenia carinifera'' Bale, 1914 * '' Aglaophenia coarctata'' Allman, 1883 * '' Aglaophenia constricta'' Allman, 1877 * '' Aglaophenia ctenata'' (Totton, 1930) * ''Aglaophenia cupressina'' Lamouroux, 1816 * '' Aglaophenia curvidens'' Fraser, 1937 * '' Aglaophenia dannevigi'' Bale, 1914 * '' Aglaophenia decumbens'' Bale, 1914 * '' Aglaophenia diegensis'' Torrey, 1904 * '' Aglaophenia difficilis'' Vervoort & Watson, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Obelia
''Obelia'' is a genus of hydrozoans, a class of mainly marine and some freshwater animal species that have both polyp and medusa stages in their life cycle. Hydrozoa belongs to the phylum Cnidaria, which are aquatic (mainly marine) organisms that are relatively simple in structure with a diameter around 1mm. There are currently 120 known species, with more to be discovered. These species are grouped into three broad categories: ''O. bidentada'', ''O. dichotoma'', and ''O. geniculata''. ''O. longissima'' was later accepted as a legitimate species, but taxonomy regarding the entire genus is debated over. ''Obelia'' is also called sea fur. ''Obelia'' has a worldwide distribution except the high-Arctic and Antarctic seas. and a stage of ''Obelia'' species are common in coastal and offshore plankton around the world.Cornelius, P.F.S., 1995b. North-West European thecate hydroids and their Medusae. Part 2. Synopses of the British Fauna (New Series), No 50. ''Obelia'' are usually fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrozoa
Hydrozoa (hydrozoans; ) are a taxonomic class of individually very small, predatory animals, some solitary and some colonial, most of which inhabit saline water. The colonies of the colonial species can be large, and in some cases the specialized individual animals cannot survive outside the colony. A few genera within this class live in freshwater habitats. Hydrozoans are related to jellyfish and corals and belong to the phylum Cnidaria. Some examples of hydrozoans are the freshwater jelly (''Craspedacusta sowerbyi''), freshwater polyps ('' Hydra''), ''Obelia'', Portuguese man o' war (''Physalia physalis''), chondrophores (Porpitidae), "air fern" (''Sertularia argentea''), and pink-hearted hydroids (''Tubularia''). Anatomy Most hydrozoan species include both a polyp (zoology), polypoid and a medusa (biology), medusoid stage in their lifecycles, although a number of them have only one or the other. For example, ''Hydra'' has no medusoid stage, while ''Liriope tetraphylla, Lir ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metridium Senile
''Metridium senile'', or frilled anemone, is a species of sea anemone in the family Metridiidae. As a member of the genus ''Metridium'', it is a type of plumose anemone and is found in the seas off north-western Europe and both the east and west coasts of North America. Description The base of ''Metridium senile'' is considerably wider than the column and is attached to rock or another substrate. The column is long, smooth and cylindrical, of a fleshy consistency with a slimy surface lubricated with mucus. There are no warts or suckers and the column is topped by a parapet and deep groove. The oral disc is broad and deeply lobed into several curving sections that overhang the column. The slender, pointed tentacles are very numerous in larger specimens though fewer and relatively longer in smaller ones. Those near the margin are crowded and short whereas further into the disc they are longer and more dispersed. The colour range of this sea anemone is large but for any one spec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aggregating Anemone
The aggregating anemone (''Anthopleura elegantissima''), or clonal anemone, is the most abundant species of sea anemone found on rocky, tide swept shores along the Pacific coast of North America. This cnidarian hosts endosymbiotic algae called zooxanthellae that contribute substantially to primary productivity in the intertidal zone. The aggregating anemone has become a model organism for the study of temperate cnidarian-algal symbioses. Description The polyps of the aggregating anemone reach up to eight cm across the oral disk with approximately 100 tentacles in three or four rows around the margins of the oral disk. Most are olive to bright green (depending on the species of algal symbionts present) with tentacles tipped in pink. Individuals that live in microhabitats that are deficient in photosynthetically active radiation (PAR), such as under docks or in caves, lack symbionts and are pale yellow to white in color. Range Pacific coast of North America from Alaska, Uni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
