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An order of neoteleost fishes which is probably the sister group to all other neoteleosts (that is, Ateleopodomorpha, Cyclosquamata, Scopelomorpha, Lampriomorpha, Polymixiomorpha, Paracanthopterygii, and Acanthopterygii). The following characters serve to distinguish the Stomiiformes: body form long and slender to very deep, and moderately to extremely compressed; luminescent organs (photophores) present below axis of body; chin barbel present in some; premaxilla and maxilla toothed and in gape of mouth; gape extending well past eye in most species; scales, if present, cycloid and easily lost; pectoral, dorsal, or adipose fins absent in some; ventral adipose fin (in front of anal fin) present in some; 4 to 9 pelvic fin rays; 5 to 24 branchiostegal rays; and color usually dark brown or black, silvery in some.
Industry:Science
An order of oceanic, mostly deep-water fishes that are structurally diverse and rare; most of the 41 species are known from one or a few specimens. Thus, their scientific study has been hindered, the anatomy is imperfectly known, and the relationships are in dispute. Five of the 10 families and 11 of the 21 genera currently placed in the order have been described since World War II. There is no fossil record.
Industry:Science
An order of Paleozoic tetrapods that arose Carboniferous (Mississippian) (345 million years ago) and lasted until the Early Triassic (about 245 mya). The term anthracosaurs (meaning “coal reptiles”) encompasses a range of genera that may not all be close relatives; rather, they form a stem group (members of the lineage leading to amniotes, but not amniotes themselves) possibly related to amniotes (reptiles, birds, and mammals). They share a number of features, such as the pattern of skull roof bones and vertebral construction, that distinguish them from temnospondyls, a larger group of Paleozoic tetrapods that are more closely related to modern amphibians. Anthracosaurs also share a number of features that may be primitive for tetrapods, including a “skull table” unit that is only loosely attached to the cheek, and a palate in which bones almost meet along the midline.
Industry:Science
An order of parasitic flagellate protozoa belonging to the class Zoomastigophorea. P. P. Grassé suggested that there should be eight orders of these parasitic (and symbiotic) zooflagellates, all in a superorder Metamonadina, but this may be an oversimplification. All retortamonads are medium to large in size and have a complicated blepharoplast-centrosome-axo-style apparatus. Retortamonadida have two or four flagella, one turned ventrally into a cytostomal depression. The nucleus, containing a distinct endosome, is located at the anterior tip. The body is twisted. These organisms are actually symbionts, ingesting bacteria in the digestive tracts of their hosts.
Industry:Science
An order of placental mammals containing the largest and most powerful living terrestrial mammals—the elephants. Proboscideans once had a wide distribution, reaching every continent except Australia and Antarctica. Although early forms lacked both significant tusks and a proboscis, they are still formally considered proboscideans.
Industry:Science
An order of placental mammals including shrews, moles, and hedgehogs. The tree shrews (Tupaiidae) and elephant shrews (Macroscelididae) are now recognized as unrelated, and they are placed in separate orders (Scandentia and Macroscelidea). Formerly thought to be the basal placental order, from which other orders were derived, the Insectivora is now restricted to members of the former suborder Lipotyphla. It evolved side by side with the other placental orders, with a fossil record going back to the Paleocene. A number of fossil families from the Cretaceous and early Tertiary, formerly included in the Insectivora, are classified as Proteutheria.
Industry:Science
An order of Pogonophora, a group of elongate, tentaculated, tube-dwelling, sedentary, nonparasitic marine worms lacking a digestive system. In this order the “coelomic” space in the anterior tentacular region is horseshoe-shaped, and the excretory (osmoregulatory) portion of its ducts come close together medially near the median, adneural blood vessel. The spermatophores are generally broad and leaf-shaped. The tube is often rigid anteriorly. The species in this order are usually large (0.04–0.12 in. or 1–3 mm in diameter) and multitentaculate.
Industry:Science
An order of predominantly long-legged, long-necked wading birds including herons, ibises, spoonbills, storks, and their allies, and also the hawklike New World vultures which were previously placed in the Falconiformes. The flamingos have traditionally been placed in this order; however, they show a number of unique features and differences and so are placed in a separate order, Phoenicopteriformes. Some workers have suggested that the ibises are members of the Charadriiformes and that the herons should be placed in a separate order; however, these suggestions are controversial.
Industry:Science
An order of primitive copepod crustaceans first discovered in 1911 in shallow waters off the coast of Norway and now known in the North Pacific as well as the North Atlantic. Copepods, along with insects and nematode worms, are one of the three mega-abundant groups of multicelled animals on Earth. Members of the Platycopioida (platycopioids) are tiny copepods. None has a body length greater than 1.0 mm (0.04 in.) and little is known of the biology of the 11 described species. Their scientific significance stems from their position as the first offshoot at the base of the copepod evolutionary tree. They retain a suite of exceptionally primitive characters that generate insight into the features presumed present in the ancestors of all copepods. These primitive characters relate to the segmentation pattern of the antennules and to the arrangement of spines on the five pairs of swimming legs.
Industry:Science
An order of protozoa in the class Myxosporidea (subphylum Cnidospora). It is characterized by production of spores with a relatively thick, single intrasporal filament and three uninucleate sporoplasms. The spore membrane occurs as a single piece. <i>Helicosporidium parasiticum</i> is the only species in the order. The parasite infests the body cavity, fat bodies, and ganglia of mites (<i>Hericia hericia</i>) and the body cavity of fly larvae (<i>Dasyhelea obscura</i> and <i>Mycetobia pallipes</i>) found in the sap of horse chestnut and elm trees.
Industry:Science
