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An order of the true mosses (subclass Bryidae) found in Australia and New Zealand. The order consists of a single species, <i>Mittenia plumula</i>, which is adapted for growth in caves or cavelike places. Branches of the persistent protonema consist of spherical cells which reflect light from a backing of chloroplasts, thus providing a glow. The stems are simple and erect, and the leaves are 2–4-ranked and oblong-lingulate and blunt or apiculate. The midrib ends above the midleaf, and the cells are short and smooth. The sporophytes are terminal, the setae elongate, and the capsules erect and oblong-cylindric. The opercula are conic-subulate. The peristome consists of 16 filiform teeth, inrolled when moist and recurved when dry, and 32 smooth, hyaline, nodulose segments attached to a short membrane. The calyptrae are mitrate and smooth.
Industry:Science
An order of the true mosses (subclass Bryidae) that grow in dull, dark tufts on soil or soil-covered rock, generally in calcareous areas. The Encalyptales consist of a single family and two genera, the better known being <i>Encalypta</i>, the extinguisher moss, so called because of its long calyptra of candle-snuffer form. The leaves resemble some of the Pottiales in shape and papillosity, but the ladderlike thickenings of the basal cells and the peristome characters indicate a fairly distant relationship.
Industry:Science
An order of the true mosses (subclass Bryidae), consisting of a single species, <i>Schistostega pennata</i>, the cave moss, which is especially characterized by its leaf arrangement and the form of its protonema. The plants grow in dimly lit, cavelike places, such as the undersides of upturned tree roots. The cave moss is widely distributed in north temperate regions. An unrelated moss in Australia and New Zealand, <i>Mittenia plumula</i>, has an identical protonema and habitat.
Industry:Science
An order of the true mosses (subclass Bryidae), whose members are remarkable perennial plants that grow mainly on nitrogenous substrates, such as dung, and show considerable differentiation of neck tissue below the spore-bearing part of the capsule. Many of the species show adaptations that encourage insect dispersal of spores. The order consists of two families with about eight genera.
Industry:Science
An order of the true mosses (subclass Bryidae). Also known as the Hypnobryales, this order consists of 14 families and some 135 genera, primarily put together because they share a hypnoid peristome (as described below). The families show considerable sporophytic unity; it is gametophyte structure that determines family membership.
Industry:Science
An order of the Turbellaria (of the phylum Platyhelminthes) known commonly as planaria, which are several millimeters to 20 in. (50 cm) or more in length. They have a diverticulated intestine with a single anterior branch and two posterior branches separated by a plicate pharynx or pharynges. Rhabdites are numerous and, except in cave planarians, two to many eyes are present. The much branched protonephridial tubules form a network with numerous nephridiopores on each side of the body. The female reproductive system includes a single pair of small anteriorly located ovaries, numerous minute yolk glands arranged in clusters along either side of the body, the common ducts, the female antrum, and usually one or more bursae. The male system has several to many testes, which are lateral in position and connected with a single sperm duct on each side. These ducts empty either directly or after fusion into the copulatory organ which lies in the male antrum. Following copulation and mutual insemination, capsules containing several fertilized eggs are attached to objects in the water and hatch in 2 or more weeks into young worms. Asexual reproduction by fission is common in forms such as the cosmopolitan <i>Dugesia tigrina</i> which has been much used in studies on regeneration. Fragmentation and regeneration is the usual method of reproduction in some land planarians such as <i>Bipalium kewense</i>, an exotic species which has become established through much of the southern United States. The marine planarian <i>Bdelloura candida</i> is a commensal on the horseshore crab.
Industry:Science
An order of very specialized deep-bodied fishes near the holostean level of organization that are known only from the fossil record. They were a widespread group that first appeared in the Upper Triassic of Europe with the genus <i>Eomesodon</i>, flourished during the Jurassic and Cretaceous (<i>Gyrodus, Coelodus, Gyronchus, Proscinetes, Mesturus</i>, and others), and persisted to the Upper Eocene (<i>Pycnodus</i> and <i>Palaeobalistum</i>). Pycnodontiforms are a closely interrelated group most commonly found preserved in marine limestone and associated with coraliferous facies.
Industry:Science
An order of wingless insects with soft, fusiform bodies 0.12–0.8 in. (3–20 mm) long, often covered with flat scales forming diverse patterns. The mouthparts are free with dicondylous mandibles used for scraping and chewing. Antennae are long and threadlike (filiform) with muscles present only in the scape and pedicel. Visual organs may be a cluster of simple ommatidia (cylinder-shaped units of a compound eye) or lacking altogether. The abdomen terminates in three “tails”: a pair of lateral cerci and a median caudal filament (telson). Females have well-developed ovipositors; males have a penis and often one or rarely two pairs of parameres.
Industry:Science
An order or (superorder) in the gastropod molluscan subclass Pulmonata containing three families of sluglike mollusks that lack any trace of a shell, have separate external male and female orifices, lack a mantle cavity, have a posterior anus and excretory pore, and bear eyes on the tops of two contractile, but not retractile, tentacles. The Rathouisiidae include about 30 species of carnivorous land slugs and range from South China and India to Queensland, Australia, in very wet tropical forests. They have slender, often brightly colored bodies. The Veronicellidae comprise about 200 species of slugs that feed on decaying plant matter. Their distribution is now pantropical (including Florida and south Texas), owing to accidental horticultural introductions. They are minor garden and crop pests in several subtropical and tropical areas. They have long flattened bodies with usually dull colors and are very abundant nocturnally in garden and lawn areas. The Onchidiidae include perhaps 250 species of intertidal to high-subtidal dwellers, reaching greatest abundance in the rocky shore areas of the tropics. They range from a few inches to nearly 4 in. (100 mm) in length. Many species have dorsal eyespots or branchial plumes present, and can be confused with opisthobranch snails.
Industry:Science
An order or suborder of the gastropod molluscan subclass Pulmonata containing about 20,500 species that are grouped into 56 families. Nearly all land snails without an operculum are stylommatophorans. They have eyespots on the tips of a pair of retractile tentacles, hermaphroditic reproduction with partial fusion of the male and female system, a single external genital orifice (or, rarely, two openings that are side by side), and, normally, a second pair of retractile tentacles that function as chemoreceptors. All are air-breathing and most are truly terrestrial. Three orders, based on excretory structures, are recognized. The more primitive Orthurethra and Mesurethra have less efficient water conservation devices than do the more specialized members of the order Sigmurethra, in which a closed ureter functions in water conservation. The latter specialization apparently is a prerequisite for evolution toward a sluglike structure, since all 16 families with slugs or sluglike taxa belong to the Sigmurethra.
Industry:Science
