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Hydranthea
''Hydranthea'' is a genus of cnidarians belonging to the family Lovenellidae. Like other Hydrozoans they are colonial. They have hydrorhiza connected to tubular stolons attaching them to other objects, like algae, kelp, rocks and crabs. Description Hydranthea have small smooth hydrophores placed irregularly along their hydrorhiza, of variable length - though they tend to be shorter. They have elongated polyps along their stems. Their bodies are pale gold in color, with a thin white band below the hypostome, an appendage on their mouth. Their tentacles, of which they have 30 per whorl, are long and colorless and connected to each other at their bases by an intertentacular web. They have around two to three Nematocysts between each set of tentacles on this web. Hydranthea have oval gonophores, a reproductive structure, on their hydrorhiza. They are dieoecious, with usually only one sex, male or female, present within a single colony. Behavior Hydranthea are active and capa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydranthea Margarica
''Hydranthea'' is a genus of cnidarians belonging to the family Lovenellidae. Like other Hydrozoans they are colonial. They have hydrorhiza connected to tubular stolons attaching them to other objects, like algae, kelp, rocks and crabs. Description Hydranthea have small smooth hydrophores placed irregularly along their hydrorhiza, of variable length - though they tend to be shorter. They have elongated polyps along their stems. Their bodies are pale gold in color, with a thin white band below the hypostome, an appendage on their mouth. Their tentacles, of which they have 30 per whorl, are long and colorless and connected to each other at their bases by an intertentacular web. They have around two to three Nematocysts between each set of tentacles on this web. Hydranthea have oval gonophores, a reproductive structure, on their hydrorhiza. They are dieoecious, with usually only one sex, male or female, present within a single colony. Behavior Hydranthea are active and cap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydranthea Phialiformis
''Hydranthea'' is a genus of cnidarians belonging to the family Lovenellidae. Like other Hydrozoans they are colonial. They have hydrorhiza connected to tubular stolons attaching them to other objects, like algae, kelp, rocks and crabs. Description Hydranthea have small smooth hydrophores placed irregularly along their hydrorhiza, of variable length - though they tend to be shorter. They have elongated polyps along their stems. Their bodies are pale gold in color, with a thin white band below the hypostome, an appendage on their mouth. Their tentacles, of which they have 30 per whorl, are long and colorless and connected to each other at their bases by an intertentacular web. They have around two to three Nematocysts between each set of tentacles on this web. Hydranthea have oval gonophores, a reproductive structure, on their hydrorhiza. They are dieoecious, with usually only one sex, male or female, present within a single colony. Behavior Hydranthea are active and cap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydranthea Diaphana
''Hydranthea'' is a genus of cnidarians belonging to the family Lovenellidae. Like other Hydrozoans they are colonial. They have hydrorhiza connected to tubular stolons attaching them to other objects, like algae, kelp, rocks and crabs. Description Hydranthea have small smooth hydrophores placed irregularly along their hydrorhiza, of variable length - though they tend to be shorter. They have elongated polyps along their stems. Their bodies are pale gold in color, with a thin white band below the hypostome, an appendage on their mouth. Their tentacles, of which they have 30 per whorl, are long and colorless and connected to each other at their bases by an intertentacular web. They have around two to three Nematocysts between each set of tentacles on this web. Hydranthea have oval gonophores, a reproductive structure, on their hydrorhiza. They are dieoecious, with usually only one sex, male or female, present within a single colony. Behavior Hydranthea are active and cap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydranthea Aloysii
''Hydranthea'' is a genus of cnidarians belonging to the family Lovenellidae. Like other Hydrozoans they are colonial. They have hydrorhiza connected to tubular stolons attaching them to other objects, like algae, kelp, rocks and crabs. Description Hydranthea have small smooth hydrophores placed irregularly along their hydrorhiza, of variable length - though they tend to be shorter. They have elongated polyps along their stems. Their bodies are pale gold in color, with a thin white band below the hypostome, an appendage on their mouth. Their tentacles, of which they have 30 per whorl, are long and colorless and connected to each other at their bases by an intertentacular web. They have around two to three Nematocysts between each set of tentacles on this web. Hydranthea have oval gonophores, a reproductive structure, on their hydrorhiza. They are dieoecious, with usually only one sex, male or female, present within a single colony. Behavior Hydranthea are active and cap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lovenellidae
__NOTOC__ Lovenellidae is a family of hydrozoans. Their hydroids live together in upright stolonal or sympodial colonies, and their gonophores are pedunculate free-roaming medusae.Schuchert (2005) The relationships of this fairly small but distinctive radiation to other members of the order Leptothecata are not well understood at present. Description The elongated, everted- conical to bell-shaped hydrothecae are pedicellate. They have a diaphragm and a conical operculum apically to the hydrothecal wall, formed either by this wall or by separated embayments of the hydrothecal margin, with a lining of triangular plates. The tentacles of some but not all carry webbing between them. The hydrothecae wear down during the individual hydroids' life, and old ones often have just the collar-like bottom of the hydrotheca remaining. The manubrium of the medusae is short. They lack a gastric peduncle, ocelli (making them effectively blind) and excretory pores, and have 4 simpl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cnidaria
Cnidaria () is a phylum under kingdom Animalia containing over 11,000 species of aquatic animals found both in freshwater and marine environments, predominantly the latter. Their distinguishing feature is cnidocytes, specialized cells that they use mainly for capturing prey. Their bodies consist of mesoglea, a non-living jelly-like substance, sandwiched between two layers of epithelium that are mostly one cell thick. Cnidarians mostly have two basic body forms: swimming medusae and sessile polyps, both of which are radially symmetrical with mouths surrounded by tentacles that bear cnidocytes. Both forms have a single orifice and body cavity that are used for digestion and respiration. Many cnidarian species produce colonies that are single organisms composed of medusa-like or polyp-like zooids, or both (hence they are trimorphic). Cnidarians' activities are coordinated by a decentralized nerve net and simple receptors. Several free-swimming species of Cubozoa and Scyphozo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sanda Island
Sanda Island ( gd, Sandaigh) is a small island in Argyll and Bute, Scotland, off the southern tip of the Kintyre peninsula, near Southend and Dunaverty Castle. On clear days Sanda can be seen from the southern tip of the Kintyre peninsula, from the Isle of Arran and from northeast County Antrim. It is known locally on Arran and on the Antrim coast as "Spoon Island" because of its resemblance to an upturned spoon. Population In the 2001 census Sanda was one of four Scottish islands with a population of just one person. However, since then there has been some development, and in 2008 the island had a population of 3. In August 2008 the island was put up for sale by the husband and wife owners as a result of their separation at a price of £3.2 million, and in January 2009 they announced that a sole caretaker would be resident until spring viewings re-commenced. The island was eventually sold to Swiss businessman Michi Meier for the reduced price of £2.5 million. The island's gro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haleciidae
Haleciidae is a family of hydrozoans. Their hydroid colonies emerge from a creeping hydrorhiza and usually form upright branching colonies, although some species' colonies are stolonal. Their gonophores are typically sporosacs, growing singly or bunched into a glomulus. They remain attached to the hydroids or break off to be passively drifted away; in a few, the gonophores are naked.Schuchert (2005) Some enigmatic actively swimming medusae have been tentatively placed in this family as a kind of " wastebin taxon". Should their associated hydroids turn out to belong elsewhere, they are to be moved to that family and genus. The relationships of this fairly small but distinctive radiation to other families of Leptothecata are not well understood at present. However, the family Lovenellidae, often turn out to contain the hydroid stage of medusae formerly placed in the family Haleciidae. Description The shallow, usually even-rimmed hydrothecae are sessile or borne on a hydr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydractinia Phialiformis
''Hydractinia'' is a genus of commensal athecate hydroids which belong to the family Hydractiniidae. ''Hydractinia'' species mostly live on hermit-crabbed marine gastropod shells. One species, '' Hydractinia echinata'', is commonly known as snail fur. Another species, ''H. minoi'', is known to be commensal with stingfishes of the genus ''Minous ''Minous'', is a genus of marine ray-finned fishes, it is the only genus in the tribe Minoini, one of the three tribes which are classified within the subfamily Synanceiinae within the family Scorpaenidae, the scorpionfishes and their relatives. ...''. Species References ''Hydractinia''at World Register of Marine Species Hydractiniidae Hydrozoan genera {{anthoathecata-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gonophore
A gonophore is a reproductive organ in Hydrozoa that produces gametes. It is a sporosac, a medusa or any intermediate stage. The name is derived from the Greek words (, that which produces seed) and (, -bearing). Gonophores are borne on branching stalks that grow out as a ring from the hydranth (i.e. the hydroid polyp, bearing a mouth, digestive cavity and tentacles) wall. The germ cells are formed from the inner layer of the entocodon. The entocodon is the primordium (i.e. the first cells that give rise to the development of an organ) of the subumbrella (i.e. the concave oral surface of a medusa) in the development of medusae from the gonophore. The gonophores in the order Leptomedusae are borne on much reduced hydranths and are usually protected in a peridermal (i.e. belonging to a hydroid perisarc) gonotheca. Medusae forming on fully developed hydranths are extremely rare; usually the gonophores develop into medusae or into sessile sporosacs. The gonophores in the superfam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dieoecious
Plant reproductive morphology is the study of the physical form and structure (the morphology) of those parts of plants directly or indirectly concerned with sexual reproduction. Among all living organisms, flowers, which are the reproductive structures of angiosperms, are the most varied physically and show a correspondingly great diversity in methods of reproduction. Plants that are not flowering plants (green algae, mosses, liverworts, hornworts, ferns and gymnosperms such as conifers) also have complex interplays between morphological adaptation and environmental factors in their sexual reproduction. The breeding system, or how the sperm from one plant fertilizes the ovum of another, depends on the reproductive morphology, and is the single most important determinant of the genetic structure of nonclonal plant populations. Christian Konrad Sprengel (1793) studied the reproduction of flowering plants and for the first time it was understood that the pollination process ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nematocysts
A cnidocyte (also known as a cnidoblast or nematocyte) is an explosive cell containing one large secretory organelle called a cnidocyst (also known as a cnida () or nematocyst) that can deliver a sting to other organisms. The presence of this cell defines the phylum Cnidaria (corals, sea anemones, hydrae, jellyfish, etc.). 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. Structure and function Each cnidocyte contains an organelle called a cnida, cnidocyst, nematocyst, ptychocyst or spirocyst. This organelle consists of a bulb-shaped capsule containing a coiled hollow tubule structure attached to it. An immature cnidocyte is referred to as a cnidoblast or nematoblast. The externally oriented side of the cell has a hair-like trigger called a cnidocil, which is a mechano- and chemo-receptor. When the trigger is activated, th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
