The latter species has a smooth, valvatiform, dextrally coiled teleoconch and a sinistral, anastrophic protoconch.
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The latter species has a smooth, valvatiform, dextrally coiled teleoconch and a sinistral, anastrophic protoconch.
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Similar to all Porcellioidea, the shell axes of the dextrally coiled early shell and teleoconch are parallel.
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Thus, the gerontic aperture of these dextrally coiled shells is situated on the left side in apertural view.
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Both species described here are sinistrally coiled, but a similar pattern of ornamentation is present on two Pennsylvanian species that are dextrally coiled.
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We thus speculate that the subducted part of the WPB, dextrally offset along the LOFZ, extends beneath the Ryukyu Arc up to the latitude of Kyushu.
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Several small river branches are dextrally offset along the fault trace, but due to the complexity of the drainage pattern it is difficult to measure total offsets.
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The teleoconch is dextrally coiled, but the larval shells are sinistral. This results in a sinistrally coiled protoconch. The columella has usually one, but sometimes several, spiral folds. The aperture is closed by an operculum.
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The adult shell, the teleoconch is dextrally coiled, but the larval shells are sinistral. This results in a sinistrally coiled protoconch. The opening of the shell, the aperture is closed by a lid, a so called operculum.
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There is a genus form the Upper Silurian, Peismoceras' which is included in the Lechritrochoceratidae, the only barradeocerin from that epoch, which could be ancestral, without having to account for any significant temporal gap. The problem is that Peismoceras is coiled dextrally, right handedly.
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Similar to other trochid snails, such as the more commonly occurring Chlorostoma species (or Tegula), the dextrally coiled shell of Norrisia norrisii is also more globose and shows a depressed-turbinate shape.Keen, A.M. and E. Coan. 1974. Marine molluscan genera of western North America. Second edition.
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The shell of these snails has a blunt, heterostrophic protoconch, which is wrapped up. The texture of these shells is sculptured with ribs. Their color is mostly white, brown, cream or yellowish, sometimes with red or brown lines. The teleoconch is dextrally coiled, but the larval shells are sinistral.
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The shell of these snails has a blunt, heterostrophic protoconch, which is often wrapped up. The texture of these shells is sculptured in various forms such as ribs and spirals. Their color is mostly white, cream or yellowish. The teleoconch is dextrally coiled, but the larval shells are sinistral.
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Larvae have a case that is dextrally coiled, with the coils incompletely fused. The head, in dorsal view, is rounded with marginal carina and covered by loosely distribute setae. The posterior part of frontoclypeal is slender. In lateral view, the head is dorsally straight with eyes erected dorsad.
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There is little known about their life histories. Most species are only known from their shells. Most species have a white of yellowish, minute, conical to ovate-conical shell, usually between 2 mm and 5 mm. The apex is rather obtuse or nipple-shaped, sinistrally or dextrally oriented to the teloconch.
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Larva: The case is dextrally coiled, with coils usually completely fused. Head is oval in dorsal view and smooth except for long setae and lateral carina. In lateral view the head has a trianguloid shape with the dorsal margin straight or slightly concave. Pronotum is strongly sclerotized while meso-and metantoum are weakly sclerotized.
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Members of this family are shaped rather like bonnets or helmets, as their common name suggests. The shells are large, thick, subglobular with dextrally coiled, sometimes varicose, whorls, and a short spire. The coiling may be trochospiral or convoluted. The shells of many species have great variability, which has led to many misidentifications, resulting in many synonyms.
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The genus Tubospirina is very similar to the genus Spirina, but it can be distinguished by the dextrally coiled shell with a flatly arched upper side. The shells are large, with a wide aperture and a characteristic ornamentation of rounded costae and interspaces. This new genus has been tentatively placed close to the genus Spirina in the family Craspedostomatidae.
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Its dextrally coiled substrate-cemented tube, bulbous initial chamber, vesicular tube wall and pseudopunctate microlamellar shell structure closely resembles trypanoporids (Tentaculita), but Anticalyptraea differs in having the cones of the pseudopunctae oriented in the opposite direction. Pseudopunctae oriented similarly to Anticalyptraea occur in Cornulites (cornulitids) and thick-walled tentaculitids. The name Anticalyptraea is a reference to the gastropod genus Calyptraea.
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Morphologically, Andiva most closely resembles Ovatoscutum, Chondroplon and, more distantly, Dickinsonia, as part of the proposed phylum Proarticulata. Archaeaspinus and Cyanorus have also been directly compared to it. Jerzy Dzik includes Andiva in the Dipleurozoa, with Chondroplon as the closest relative, separated from Dickinsonia and closer to Yorgia, Praecambridium, Archaeaspinus and Vendia, since all of them are sharing a dextrally bent dorsal medial chamber.
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To the south, it passes the towns of Garzón, Altamira, Timaná, Pitalito and San Agustín. In Pitalito, it creates a pull-apart basin. The fault appears to dextrally displace the Suaza Fault. The place of the offset is marked by a large shutter ridge near where the Suaza River was dammed by huge landslides as a result of the earthquake of November 16, 1827.
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The shell is coiled dextrally (i.e. clockwise). The thin, double-walled keel of the shell extends outward from the last shell whorl. The apex of the shell is found on the right side, the umbilicus on the left side. The shell and keel can be calcareous (genus Atlanta), or composed exclusively of conchiolin (genus Oxygyrus), or the shell can be calcareous and its keel composed of conchiolin (genus Protatlanta).
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Longitudinals—there are on the body whorl 16 narrow, raised, dextrally convex, and rather oblique ribs; originating at the angle of the whorls, where they are a little tubercled and swollen. They are parted by furrows of about the same breadth as themselves. They die out across the base, and do not appear on the aperture. There are about 13 ribs on the penultimate whorl, and they diminish rapidly up the spire.
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Species in the genus Amphidromus usually have smooth, glossy, brightly colored, elongate or conic, dextrally or sinistrally coiled shells. The shells are moderately large, ranging from to in maximum dimension, having from 6 to 8 convex whorls. Their color pattern is usually monochromatic yellowish or greenish, but can be variegated. The aperture is oblique or ovate in shape, without any teeth or folds, and with the aperture height ranging from two-fifths to one-third of total shell height.
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Photograph of genetalia of a male Empis vitripennis. Note the asymmetrical tergite 8 on the left side of the epiandrium The abdomen is elongate-conical or flat. The genitalia of the male often are free and borne on a petiole, with tergite 8 being asymmetrical, lying on the left side of the epandrium. They are also rotated dextrally between 90° and 180°, including segment 8 and sometimes segment 7, which makes them distinguishable from the family Hybotidae.
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Oxygonioceras is a genus in the Oncocerid family, Brevicoceratidae, from the Middle Silurian of North America and Europe. Oxygonioceras, named by Foeste, 1925, has a loosely coiled, dextrally torticonic shell with a rounded dorsum on the inside of the spiral and an angular or subangular venter on the outside; suture with broad lateral lobes and ventral siphuncle with expanded, nummuloidal segments. Although also torticonically gyroconic—having an out of plane open spiral - Oxygonioceras differs from Naedyceras and closely related genera in that the siphuncle segments are empty, rather than being actinosiphonate.
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In strike-slip faults the blocks slide past each other laterally, and in this case they do so in a counter-clockwise direction or dextrally, similar to the famous San Andreas Fault. Remarking on it as a geological and physical phenomenon, Carruthers continues: > [T]he Dzungarian Gate is as unusual as that of the Jordan depression. They > are both examples of a rift-valley caused by the movement of the earth's > crust, not by the action of water. This valley once formed the connecting > link between the drainage of Dzungaria and that of Southern Siberia.
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The longitudinal sculpture shows the whorls crossed from suture to suture by low, sharpish, subangulately projecting, dextrally convex, hardly oblique ribs, which run continuously, but are slightly diminishing in number, up the spire, there being about 15 on the last and 11 on the first regular whorl. On the base they bend strongly to the right, and die out at the point of the snout. They are parted by hollowed furrows which are rather broader than they. Both ribs and furrows are scratched with very fine, almost microscopic lines of growth, which coincide with the course of the ribs.
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Karakoram fault information modified from and superimposed on top of topographic map of region. EPM= East Pamir Mountains It is suggested that a late Cretaceous-Eocene granite batholith had been offset 1000 km dextrally along the Karakoram Fault based on mapping in the central Karakoram, in nearby Ladakh-Zanskar, and in south Tibet. Some researchers suggest that this might be incorrect due to associating granite that was never part of the same batholith. Others researchers work have shown 600 km of right lateral slip since 23 million years ago, and possibly starting 34 million years ago, based on U-Pb dating.
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Right wing of the species Hybos grossipes, showing discal medial cell (dm) and first and second medial vein (M1+2) Hybos caliciformis Hybotidae share some similarities with the family Dolichopodidae, when looking at rotation of genetalia and wing characteristics. Male terminalia are rotated dextrally between 45° and 90°, excluding segment 7. Hybotidae wings always have a simple R4+5 vein, where the costa either ends near or at M1/M1+2, or near or at R4+5/R5. Furthermore, it can be distinguished from Dolichopodidae by the point of vein Rs, which it at a distance from the humeral crossvein (h) equal to or longer than the length of h.
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