955 resultados para controladores de caudal
Resumo:
A new species of hillstream loach genus Balitora Gray is discovered from Nanting River drainage, which drains to Salween, Yongde County, Yunnan, China. Balitora nantingensis can be distinguished from B. lancangjiangensis by a triangle-like blotch in nape absent vs. present; area from halfway of pelvicfin ray to anus covered by scales vs. no scales in this area; the first pectoral ray thickened vs. not; posterior end of pelvic-fin surpasses middle point from posterior end of pelvic-fin base to anal-fin origin vs. the end from posterior extremity of pelvic-fins to anus; fewer lateral line scales, 59-64 vs. 66-70; slightly longer head, SL 4.2-5.1 (4.6) times of HL vs. 5.0-5.9 (5.4); slightly larger eyes, HL 4.0-6.4 (5. 1) times of eye diameter vs. 5.5-7.5 (6.3). Balitora nantingensis can be distinguished from B. burmanica by body rounded vs. slender in dorsal view; pointed snout vs. blunt in dorsal view; a deeper body, body depth 12.5-16.9% of SL vs. 10-12%; a deeper caudal-peduncle, length of caudal-peduncle 2.0-2.8 times of its depth vs. 3.0-4.2; a shorter caudal-peduncle, 14.3-15.6% of SL vs. 16-21%; the average ratio of body width at pelvic-fin origin and distance between inner pelvic-fin base 2.0 vs. 3.4; body width 1.1-1.5 times of body depth vs. 1.5-1.6; posterior end of pelvic-fin almost one or slight more than one eye diameter from anus vs. closet to anus; outside rays of pelvic-fin extend more posteriorly than inside rays and make posterior outline of fin acclivitous and straight vs. the outside ones almost equal to the inside ones and make the fin slightly convex.
Resumo:
Schistura cryptofasciata is distinguished from its congeners by following combination characters: lateral line complete; 8(1)/(2) branched dorsal-fin rays; 9+8 branched caudal-fin rays; no sexual dimorphism; 8-11 indistinct bars, wider than interspaces; caudal-peduncle length 44.1-16.5% standard length, 68.1-90.4% dorsal head length; anterior portion of body scaleless; air bladder entirely embedded in bony capsule; lateral head length 104-122% dorsal head length; lower jaw with a notch at symphysis; lower lip completely interrupted; interorbital width 1.9-2.2 times eye diameter; pelvic-fin origin ventral to dorsal-fin origin; anus 1.0-1.5 eye diameters in front of anal-fin origin; the widest part of black basal caudal bar is the midlateral, and then the upper and lower ends.
Resumo:
A new blind loach of Triplophysa Rendahl 1933 was collected from a subterranean pool in a cave at Wulong County, Chongqing City, China, in November 2002. The new species, named Triplophysa rosa sp. nov., can be distinguished from its congeners by the following unique characters: eyes vestigial; 9 branched dorsal-fin rays; 12 branched pectoral-fin rays; 7 branched pelvic-fin rays; 6 branched anal-fin rays; 7 + 7 branched caudal-fin rays; distal margin of dorsal-fin concave; tip of pelvic-fin surpasses vertical level of anus; caudal-fin deeply forked; whole body scaleless and colourless. (c) 2005 The Fisheries Society of the British Isles.
Resumo:
A new species of the genus Paracobitis, Paracobitis nanpanjiangensis is described from tributaries of the Nanpanjiang River drainage in China. It is distinguished from its congeners, except P. oligolepis and P. wujiangensis, by body scaleless or with rudimentary scales (caudal peduncle with several deeply embedded scales). It can be differentiated from P. wujiangensis by the complete lateral line (vs. incomplete), lower dorsal crest reaching the vertical of origin of anal fin (vs. shorter and higher dorsal crest not reaching the base of anal fin). It is distinguished from P. oligolepis by the following characters: branched dorsal fin with 81/2 (a few 91/2) rays (vs. 91/2), interspaces between bars in front of dorsal fin conspicuously thinner than those behind (vs. vermiform markings), dorsal head without vermiform markings or obscure (vs. clearly vermiform markings on dorsal head), vertebrae 4 + 36-38 (vs. 4 + 39-41).
Resumo:
A new species of the genus Glyptothorax, Glyptothorax obliquimaculatus sp. nov. is described from the Xiaohei River, a tributary of the Nanting River, Salween drainage, in southwestern Yunnan province, China. This new species can be distinguished from its congeners by the following combination of characteristics: unculiferous ridges of the thoracic adhesive apparatus extending anteriorly onto the gular region; body with irregular dark blotches scattered along lateral surface (blotches mostly oblique); skin smooth on head and body; dorsal spine smooth without serrations on its posterior margin; lips smooth; posterior margin of pectoral spine with 7-8 serrations; dorsal-fin base 11.0-13.2% SL; pectoral-fin length 15.6-19.6% SL; depth of caudal peduncle 8.6-9.8% SL; head width 19.1-24.0% SL; nasal barbel length 23.3-33.3% HL.
Resumo:
Two new species and a new record of Sinogastromyzon are described from Lixianjiang River of Yunnan province, China. Sinogastromyzon lixianjiangensis, new species, can be distinguished from its congeners by the following characters: pectoral fin with XIII-XIV, 15-17 rays; pelvic fin with X-XI, 10-12 rays; 60-65 lateral-line scales; no scales on the dorsum of paired fins or the region between axilla of pectoral fin and pelvic-fin origin; tip of pelvic fin close to anus; tip of anal fin close to caudal-fin base; anal-fin origin nearer to the caudal-fin base than to the posterior pelvic-fin base; anus nearer to anal-fin origin than to the posterior pelvic-fin base; dorsal side of the body with 9-11 black blotches. Sinogastromyzon macrostoma, new species can be distinguished from its congeners by the following characters: pectoral fin with XII-XIV, 12-15 rays; pelvic fin with VII-IX, 11-13 rays; 48-56 lateral-line scales; mouth extremely big, slightly arched; no scales on the dorsum of paired fins or the region between axilla of pectoral fin and pelvic-fin origin; tip of pelvic fin far beyond anus; tip of anal fin far from caudal-fin base; anal-fin origin about midway between the posterior pelvic-fin base and caudal-fin base; anus nearer to posterior pelvic-fin base than to anal-fin origin; dorsal side of the body uniformly gray, without regular blotches in formalin preserved specimen. Sinogastromyzon cf. multiocellum is firstly recorded in China.
Resumo:
Reward processing is linked to specific neuromodulatory systems with a dopaminergic contribution to reward learning and motivational drive being well established. Neuromodulatory influences on hedonic responses to actual receipt of reward, or punishment, referred to as experienced utility are less well characterized, although a link to the endogenous opioid system is suggested. Here, in a combined functional magnetic resonance imaging-psychopharmacological investigation, we used naloxone to block central opioid function while subjects performed a gambling task associated with rewards and losses of different magnitudes, in which the mean expected value was always zero. A graded influence of naloxone on reward outcome was evident in an attenuation of pleasure ratings for larger reward outcomes, an effect mirrored in attenuation of brain activity to increasing reward magnitude in rostral anterior cingulate cortex. A more striking effect was seen for losses such that under naloxone all levels of negative outcome were rated as more unpleasant. This hedonic effect was associated with enhanced activity in anterior insula and caudal anterior cingulate cortex, areas implicated in aversive processing. Our data indicate that a central opioid system contributes to both reward and loss processing in humans and directly modulates the hedonic experience of outcomes.
Resumo:
Our ability to have an experience of another's pain is characteristic of empathy. Using functional imaging, we assessed brain activity while volunteers experienced a painful stimulus and compared it to that elicited when they observed a signal indicating that their loved one--present in the same room--was receiving a similar pain stimulus. Bilateral anterior insula (AI), rostral anterior cingulate cortex (ACC), brainstem, and cerebellum were activated when subjects received pain and also by a signal that a loved one experienced pain. AI and ACC activation correlated with individual empathy scores. Activity in the posterior insula/secondary somatosensory cortex, the sensorimotor cortex (SI/MI), and the caudal ACC was specific to receiving pain. Thus, a neural response in AI and rostral ACC, activated in common for "self" and "other" conditions, suggests that the neural substrate for empathic experience does not involve the entire "pain matrix." We conclude that only that part of the pain network associated with its affective qualities, but not its sensory qualities, mediates empathy.
Resumo:
Onychostoma virgulatum, new species, is described from the Qiupu River, a tributary on the Southern bank of the lower Yangtze River at Shitai County, southern Anhui Province, South China. It shares with O. fusiforme and O. meridionale the presence of a longitudinal dark brown stripe extending along the lateral line, a character separating them from all other congeners of the moderate-mouth group diagnosed by having a slightly arched or nearly transverse mouth opening (with the extremities slightly curved posteriorly), its width being equal to or slightly less than the width of head at this same point, and a short postlabial groove extending along half of the length of the lateral margin of the lower jaw. Onychostoma virgulatum differs from both in the presence of two pairs of barbels in adults, from O. fusiforme in the body depth, caudal-peduncle depth, and position of pelvic and anal fins, and from O. meridionale in the structure of the last simple dorsal-fin ray.
Resumo:
Metzia longinasus, a new cultrine cyprinid species from the Hongshui-He River of the Pearl River drainage in Guangxi Province, southern China, is described here. It can be distinguished from all other congeners by having a combination of the following characters: a superior mouth, 43 or 44 lateral-line scales, a long head (length 27.2-30.8% of standard length), a long snout (length 31.7-37.0% of head length), 10 or 11 branched anal-fin rays, and no longitudinal black band extending along each side of body from the extremity of the gill opening to caudal-fin base.
Resumo:
Critical swimming speeds (U-crit) and morphological characters were compared between the F-4 generation of GH-transgenic common carp Cyprinus carpio and the non-transgenic controls. Transgenic fish displayed a mean absolute U-crit value 22.3% lower than the controls. Principal component analysis identified variations in body shape, with transgenic fish having significantly deeper head, longer caudal length of the dorsal region, longer standard length (L-S) and shallower body and caudal region, and shorter caudal length of the ventral region. Swimming speeds were related to the combination of deeper body and caudal region, longer caudal length of the ventral region, shallower head depth, shorter caudal length of dorsal region and L-S. These findings suggest that morphological variations which are poorly suited to produce maximum thrust and minimum drag in GH-transgenic C. carpio may be responsible for their lower swimming abilities in comparison with non-transgenic controls.
Resumo:
Pseudobagrus brachyrhabdion sp. nov., from the Yuan Jiang and Xiang Jiang of the middle Yangtze River drainage in Hunan and Guizhou Provinces, South China, is described herein. It is distinguished from all other Pseudobagrus species with a truncate or slightly emarginated caudal fin by an unique combination of the following characters: supraoccipital plate and nuchal plate broadly interspaced and covered with skin; nasal barbels only at most reaching anterior margin of eye; maxillary barbels reaching slightly beyond posterior margin of eye; outer mandibular barbels extending to posterior margin of eye; dorsal fin with a somewhat convex distal margin, origin nearer to pectoral-fin insertion than to pelvic-fin insertion; dorsal-fin spine shorter than pectoral spine, with a somewhat serrated posterior margin; pectoral-fin spine with a smooth anterior margin; anal fin with 20-23 rays, base length 23.8-32.0% of standard length, posterior end of anal-fin base anterior to posterior end of adipose fin base; no longitudinal black band extending along flank; eyes large, diameter 16.3-23.7% of head length; and number of vertebrae 5 + 43-46.
Resumo:
Triplophysa lixianensis, a new nemacheiline loach species, is described from the Min Jiang of the upper Yangtze River drainage in Sichuan Province, South China. It can be separated from all other species of Triplophysa by having a unique combination of the following characters: posterior chamber of gas bladder greatly reduced or absent; caudal peduncle columnar with a roughly round cross- section at its beginning; anterior edge of lower jaw completely exposed or uncovered by lower lip; intestine short, forming a zigzag loop below stomach; dorsal- fin origin closer to caudal- fin base than to snout tip; pelvic fin inserted anterior to dorsal- fin origin; snout length 50.6 - 57.5 % of head length; eye diameter 12.3 15.4 % of head length; caudal peduncle length 25.1 - 27.1 % of standard length; anal fin with five branched rays; lower lip greatly furrowed with two thick lateral lobes; and body smooth or scaleless.
Resumo:
Garra rotundinasus, a new cyprinid species from the upper Irrawaddy River basin in Yunnan, China, is herein described. It shares with G. gravelyi the presence of a snout having a poorly developed proboscis represented by a truncate area in front of the nostrils, a character distinguishing both from all other Southeast Asian and Chinese congeners. The two species are distinct in coloration, morphometric and meristic characters. The sympatrically occurring G. tengchongensis is very similar to G. rotundinasus in possessing 36-37 perforated lateral line scales, 5 or 6 scales between the anus and anal-fin origin, and an anterior position of the anus (anus to anal distance 32.1-51.8% of pelvic to anal distance). Garra rotundinasus can be differentiated from G. tengehongensis in having a more slender caudal peduncle, a larger disc and no dark central band on the dorsal fin.
Resumo:
Acrossocheilus malacopterus n. sp. is described from the Yuan Jiang (Red River) and Zhu Jiang basins in I South China. It is separated from other congeners by a combination of the following characters: an inconspicuously stripped body, 16 circumpeduncular scales, 47-49 lateral line scales, depth of caudal peduncle 7.8-9.3% SL, snout length 37.9-41.7% SL, dorsal-fin length 18.7-21.0% SL and last simple dorsal-fin ray slender with 8-10 fine serrations along posterior margin.