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An order of cnidarian subclass Hexacorallia commonly known as mushroom anemones. These polyps are morphologically intermediate between members of the hexacorallian orders Scleractinia (corals), with which they share features of internal anatomy, weak musculature, and certain types of nematocysts (intracellular stinging capsules used in food capture and defense), and Actiniaria (anemones), which they resemble in lacking a calcareous skeleton. All three animals have paired, coupled mesenteries that are added around the entire periphery of the polyp. Like Actiniaria and Scleractinia, Corallimorpharia contains some members that are solitary and some that are clonal (reproduce asexually to produce genetically identical individuals that live physically separate from one another); however, by contrast with Scleractinia, Corallimorpharia has no colonial members (clonemates that remain attached to one another).
Industry:Science
An order of Copepoda that includes the larger and more abundant of the pelagic species. Some authorities consider the Calanoida an order of the subclass Copepoda. In the food cycles of the sea these copepods are the most important group of marine animals because of their overwhelming numbers, ubiquitous distribution, and position at the base of the animal food chain.
Industry:Science
An order of crepuscular (active during predawn or twilight hours) or mainly nocturnal birds collectively known as the goatsuckers. The group is apparently most closely related to the owls (Strigiformes) and is found worldwide, mainly in the tropics and warm temperate regions. Species breeding in the Arctic and cooler temperate regions are migratory.
Industry:Science
An order of crustaceans in the subclass Malacostraca, which lack a carapace, bear unstalked eyes, and respire by thoracic branchiae, or gills. The abdomen usually bears three pairs of biramous swimmerets (pleopods), three pairs of rather rigid uropods, and a telson which may be lobed or entire. The body is usually flattened laterally, and the pereiopods (walking legs), unlike those of the Isopoda, are elongated so that walking is difficult. In contrast to the Isopoda, the maxillipeds lack epipodites. The sexes are separate, but reproductive and copulatory organs are very simple. The eggs are extruded by the female into a ventral brood pouch composed of setose lamellae attached to the medial bases of the legs. The young hatch as miniature adults, growing usually to a length of 0.12–0.48 in. (3–12 mm), and in exceptional cases to 5.6 in. (140 mm).
Industry:Science
An order of Devonian plants considered by some to be related to the spenophytes. The small dichotomously forked leaves tend to be borne in whorls. Some leaves bear terminal sporangia, but these appendages are neither aggregated into a tight cone nor separated by bracts.
Industry:Science
An order of Diadematacea, making up those genera that possess solid spines and a rigid test. The ambulacra show typical diadematoid structure, and the tubercles are noncrenulate. The single known family, Pedinidae, includes 15 genera, ranging from the Late Triassic onward, although only one genus, <i>Caenopedina</i>, survives today; the latter inhabits the Indo-Pacific and Caribbean seas, ranging from the continental shelf down to 660 ft (2000 m).
Industry:Science
An order of dominant, hoofed herbivores of the Cenozoic of South America that are abundantly represented in Paleocene through Pleistocene nonmarine sedimentary rocks of that continent. There are also isolated occurrences in the Paleocene of Central Asia and early Eocene of North America. Diverging from a primitive condylarth ancestry at an early date, they radiated into a wide diversity of forms, some of which were convergent with Northern Hemisphere ungulates.
Industry:Science
An order of Echinacea with a camarodont lantern, smooth or sculptured test, tubercles imperforate or perforate (and usually crenulate), ambulacral plates of diademoid or echinoid type, and branchial slits which are usually shallow. The order includes a long phylogenetic series in which the original characters change considerably so that a concise but exact diagnosis is not possible. Following is an evolutionary summary of the three included families. (1) The Glyphocyphidae, known only from the Cretaceous and Eocene and probably ancestral to the other two families, were small forms with a sculptured test, perforate crenulate tubercles, and diademoid ambulacral plates. Their sculptured test links them with (2) the Temnopleuridae whose tubercles, however, are imperforate, though usually crenulate. This family arose in the Cretaceous and abounds today, especially in the tropics, on strandlines. Most of the order, so far, had shallow branchial slits, but transitional forms link them with (3) the Toxopneustidae, Tertiary and extant forms where the slits are deep and the sculpture tends to vanish. At the same time, the tubercles become imperforate and noncrenulate and the ambulacral plates change to the echinoid type.
Industry:Science
An order of Echinothuriacea with solid and hollow primary radioles, diademoid ambulacral plates, noncrenulate tubercles, and the anus within the apical system. The extant members of the family Echinothuriidae are all deep-water forms. The Echinothuriidae have a large flexible test which collapses into a disk at atmospheric pressure, and the middle element of the diademoid plates is much larger than the other two elements. Some species carry venomous spines. Echinothuriids range from the Late Jurassic to present day.
Industry:Science
An order of ectoproct bryozoans (in which the anus opens outside the ring of tentacles) in the class Gymnolaemata. Cheilostomes possess delicate colonies composed of loosely grouped, highly complex, short, uncurved, box- or vase-shaped zooecia (chamber in which the animal lives), with solid, porous, chitinous, or calcareous walls, and with apertures closed by lidlike opercula.
Industry:Science
