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An order of the class Ascolichenes, also known as the Pyrenolichenes. As now circumscribed, the Pyrenulales includes only those lichens with perithecia that contain true paraphyses and unitunicate asci. Other pyrenolichens with pseudoparaphyses and bitunicate asci have been transferred to the Pseudosphaeriales. The flask-shaped perithecia are uniformly immersed in the medulla of the thalli with a small ostiole opening at the surface. The asci and paraphyses arise from a blackened hypothecium and line the walls of the perithecium. The spores eventually burst the ascal walls and ooze out through the ostiole in a jelly matrix. Details of ascal development have been described rather fully for <i>Dermatocarpon aquaticum</i>. The Pyrenulales are almost all crustose in growth form, with very simple internal structure. The exception is Dermatocarpaceae, large umbilicate species often confused with the typical rock tripe, <i>Umbilicaria</i>, in the Lecanorales.
Industry:Science
An order of the class Ascolichenes, shared by the class Ascomycetes. The order is also called the Pleosporales. The genera now assigned to this order were formerly classified in the Pyrenulales. They resemble the typical pyrenomycetous lichens except for the structure of the ascocarp, which is not a true perithecium. It is flask-shaped and lined with a layer of interwoven, branched pseudoparaphyses. The asci, with bitunicate walls, are located in scattered locules. Little is known about the structure and development of these ascocarps.
Industry:Science
An order of the class Bryopsida in the subclass Bryidae. The order consists of a single genus and species, <i>Bryoxiphium norvegicum,</i> the sword moss. This order is characterized by a swordlike appearance owing to leaves overlapping in two rows. The shiny, rigid leaves are keeled and conduplicate-folded. The apex is long-awned at the stem tip and progressively shorter-pointed downward. The midrib bears at back a low ridge of one to four rows of cells. The leaf cells are smooth and subquadrate within, longer and narrower toward the margins. The plants are dioecious with terminal archegonia. The capsules are immersed and have an operculum but no peristome. The calyptra is cucullate, and the haploid chromosome number 14.
Industry:Science
An order of the class Cephalopoda (subclass Coleoidea) commonly known as squids. They are characterized by 10 appendages (eight arms and two longer tentacles) around the mouth; an elongate, tapered, usually streamlined body; an internal, rod- or bladelike chitinous shell (gladius); and fins on the body. The two tentacles are strongly elastic, contractile, but not retractile into pockets as in cuttlefishes (Sepioidea). Two rows of suckers (infrequently four or six rows) occur on the arms on muscular stalks, with sucker rings that are chitinous, smooth, toothed, or modified as clawlike hooks. The muscular tentacles have terminal clubs with two rows, usually four, ranging up to many rows of suckers (and/or hooks in some families). Adults of the family Octopoteuthidae and genera <i>Gonatopsis</i> and <i>Lepidoteuthis</i> characteristically lose their tentacles.
Industry:Science
An order of the class Cycadopsida having one species, <i>Welwitschia mirabilis</i>. This plant is native to the very arid deserts of southwestern Africa. Its appearance is bizarre—it has a very short, unbranched, woody stem (sometimes to 3 ft or 1 m in diameter), which is cushion- or saucer-shaped and tapers quickly to a long taproot. There are only two leaves, and these persist throughout the life of the plant. The leaf is broadly strap-shaped, as wide as the stem, firm, and leathery, and gradually splits lengthwise between the veins. The leaf (of indefinite growth) develops from a meristem at its point of connection to the stem. The species is dioecious; the cones are borne on branched axes originating between the crown of the stem and the base of the leaf. The order is known only from the one living species and not from any fossils.
Industry:Science
An order of the class Cycadopsida of the division Pinophyta (gymnosperms) consisting of four families, Cycadaceae, Stangeriaceae, Zamiaceae, and Boweniaceae, with perhaps 100 species. The order dates from the upper Carboniferous and has few living representatives. The cycads were distributed worldwide in the Mesozoic, but today are restricted to subtropical and tropical regions, with the plants occurring in small colonies; few have broad distributions.
Industry:Science
An order of the class Enopla in the phylum Rhynchocoela. The proboscis is unarmed. The alimentary system comprises the mouth, papillate foregut, sinuous intestine without diverticula, and anus. Members are characterized by the presence of a posterior adhesive disk and dorsoventral flattening of the body, which lacks eyes, cephalic slits, and cerebral organs. The order contains the single genus <i>Malacobdella</i>, with three species ectocommensal in the mantle cavity of marine bivalves and one in the pulmonary sac of a fresh-water gastropod. <i>Malacobdella grossa</i>, in the bivalve <i>Zirfaea crispata</i>, abstracts particulate food such as planktonic organisms from the host's feeding current, collects these by a unique filtration system, and digests them in the intestine by a combination of extracellular and intracellular processes. Carbohydrases predominate in the digestive physiology, in contrast to other, carnivorous rhynchocoelans, where proteases are dominant.
Industry:Science
An order of the class Enopola of the phylum Rhynchocoela, characterized by possession of an elaborate armed proboscis consisting of an anterior thick-walled tube, a median portion armed with stylets, and a posterior blind tube. The alimentary system possesses a cecum, and in some species (such as <i>Amphiporus lactifloreus</i>) the foregut (stomach) can be everted into the prey to achieve extracorporeal digestion prior to ingestion. There are two suborders, the Monostylifera and Polystylifera, separated on the number of stylets in the proboscis. Monostylifera include fresh-water, terrestrial, and symbiotic species, as well as the more common marine littoral forms.
Industry:Science
An order of the class Ginkgoopsida having about 35 species in the genus <i>Ephedra</i>. These plants are mostly of arid regions. They include freely branched, low shrubs with reduced, scalelike leaves and green photosynthetic twigs. The species are dioecious (seldom gynodioecious). The genus is known from Asia to Europe, in northern Africa, in the United States and Mexico, and from Bolivia to Patagonia. It is not known in the fossil record.
Industry:Science
An order of the class Hirudinea (leeches) which do not have an eversible proboscis, but frequently have three jaws armed with sharp teeth. The blood of these annelids contains hemoglobin. They may be divided into the Gnathobdellae, with jaws, and the Pharyngobdellae, without jaws.
Industry:Science
