Q:Information: - Bacteria (common noun bacteria, singular bacterium) constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a number of shapes, ranging from spheres to rods and spirals. Bacteria were among the first life forms to appear on Earth, and are present in most of its habitats. Bacteria inhabit soil, water, acidic hot springs, radioactive waste, and the deep portions of Earth's crust. Bacteria also live in symbiotic and parasitic relationships with plants and animals. - Tetrodotoxin (TTX) is a potent neurotoxin. Its name derives from Tetraodontiformes, an order that includes pufferfish, porcupinefish, ocean sunfish, and triggerfish; several species that carry the toxin. Although tetrodotoxin was discovered in these fish and found in several other aquatic animals (e.g., in blue-ringed octopuses, rough-skinned newts, and moon snails), it is actually produced by certain infecting or symbiotic bacteria like "Pseudoalteromonas", "Pseudomonas," and "Vibrio" as well as other species found in the animals. - Carpilioidea is a superfamily of crabs containing a single extant family, Carpiliidae and three extinct families. The modern range of the family includes the Indo-Pacific, Western Atlantic and Caribbean Sea. The fossil record of the group extends back at least as far as the Paleocene. - Crabs are decapod crustaceans of the infraorder Brachyura, which typically have a very short projecting "tail" (abdomen) (= short, = tail), usually entirely hidden under the thorax. They live in all the world's oceans, in fresh water, and on land, are generally covered with a thick exoskeleton and have a single pair of claws. Many other animals with similar names such as hermit crabs, king crabs, porcelain crabs, horseshoe crabs, and crab lice are not true crabs. - Xanthidae is a family of crabs known as mud crabs, pebble crabs or rubble crabs. Xanthid crabs are often brightly coloured and are poisonous, containing toxins which are not destroyed by cooking and for which no antidote is known. The toxins are similar to the tetrodotoxin and saxitoxin produced by puffer fish, and may be produced by bacteria in the genus "Vibrio" living in symbiosis with the crabs, mostly "V. alginolyticus" and "V. parahaemolyticus". - The Indo-Pacific, sometimes known as the Indo-West Pacific, is a biogeographic region of the Earth's seas, comprising the tropical waters of the Indian Ocean, the western and central Pacific Ocean, and the seas connecting the two in the general area of Indonesia. It does not include the temperate and polar regions of the Indian and Pacific oceans, and the Tropical Eastern Pacific, along the Pacific coast of the Americas, is also a distinct marine realm. - Xanthoidea is a superfamily of crabs , comprising the three families Xanthidae , Panopeidae and Pseudorhombilidae . Formerly , a number of other families were included in Xanthoidea , but many of these have since been removed to other superfamilies . These include Carpilioidea , Eriphioidea , Hexapodoidea , Pilumnoidea and Trapezioidea . Even in this reduced state , Xanthoidea remains one of the most species - rich superfamilies of crabs . - Vibrio is a genus of Gram-negative bacteria, possessing a curved-rod shape (comma shape), several species of which can cause foodborne infection, usually associated with eating undercooked seafood. Typically found in salt water, "Vibrio" species are facultative anaerobes that test positive for oxidase and do not form spores. All members of the genus are motile and have polar flagella with sheaths. " Vibrio" species typically possess two chromosomes, which is unusual for bacteria. Each chromosome has a distinct and independent origin of replication, and are conserved together over time in the genus. Recent phylogenies have been constructed based on a suite of genes (multilocus sequence analysis). - Saxitoxin (STX) is a potent neurotoxin and the best-known paralytic shellfish toxin (PST). Ingestion of saxitoxin, usually by consumption of shellfish contaminated by toxic algal blooms, is responsible for the human illness known as paralytic shellfish poisoning (PSP). What is the relationship between 'xanthoidea' and 'brachyura'?
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parent taxon