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1.
应用扫描电镜和透射电镜对挂榜山小鲵(Hynobius guabangshanensis)精子的超微结构进行观察和研究.结果表明:1)挂榜山小鲵的精子形态具有小鲵科精子的共同特征:头部细直、有锥形顶体;颈部短而不明显,尾部细长、有波动膜;2)该种小鲵的精子超微结构具小鲵科物种精子的共同特征,即精子无顶体钩,顶体呈三叶草状,尾部无线粒体,轴纤维粗大呈圆柱状等;3)除精子全长(194.1±7.15μm)在小鲵科物种中属于中等外,挂榜山小鲵和本科其他物种的精子在形态量度学方面差异明显:其头部占全长的比例(22.98%)比其他已知小鲵科的物种都低,尾部占全长的比例(65.79%)比其他小鲵科物种都高. 相似文献
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2004-2006年对挂榜山小鲵(Hynobius guabangshanensis)的繁殖生态进行了观察研究.结果表明:挂榜山小鲵繁殖期为每年的11月中旬至翌年1月;非繁殖期营陆生生活,繁殖期进入水中繁殖;繁殖期活动高峰为20:00到翌日6:00;繁殖种群数量为198条,现存分布区不足10 km2;繁殖期雌雄性比为1.6,存在明显的两性异型,性成熟雌体的体长和体质量显著大于雄体;挂榜山小鲵的抱对行为与东北小鲵、黑小鲵、极北鲵相似;雄体具有求偶炫耀行为和精子竞争行为;繁殖场多为临时水凼和小而浅的池塘,大部分卵袋被固定在浅水的枯枝和水草上;挂榜山小鲵的卵袋较同科物种粗大,幼体刚出膜时卵袋长(18.40±4.21) cm(n=31),直径(4.23±0.52) cm(n=31);卵径(2.10±0.25) mm(n=45);卵粒数(88.90±20.30)个(n=98)(单个卵袋),受精率为(93.3±21.4)%(n=98). 相似文献
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湘中西部小鲵属一新种--挂榜山小鲵(两栖纲:小鲵科) 总被引:15,自引:0,他引:15
在比较和研究小鲵属Hynobius物种后 ,确定湖南省祁阳县产小鲵为一新种 ,即挂榜山小鲵Hynobiusguabangshanensissp .nov .。新种与安吉小鲵H amjiensis近似 ,它们体型较大 ;有 13条肋沟 ;前后肢贴体相向时指趾重叠较多 ;掌、突明显 ,但又有明显区别 :1)新种比安吉小鲵稍小 ,全长 139 32mm± 9 5 0mm (n=9) ;2 )犁骨齿细且排列密 ,外枝 9- 11枚、内枝 2 5 - 2 7枚 ;3)尾较短 ,平均为头体长之 70 4 % (n =9) ;4 )卵袋较短 ,香蕉形弯曲等。本文列表比较近似种 ,统计并记述了新种 相似文献
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对在内蒙古自治区新巴尔虎右旗猎捕到的蒙原羚(Procapragutturosa)亚成体的外部形态及消化道若干指标进行了测量及分析,结果表明,蒙原羚亚成体的体重平均为27.47kg,体长平均为105.37cm,尾长平均为10.94cm,肩高平均为56.55cm。蒙原羚亚成体胃(含胃容物)的总重为5.26kg,占体重的19.15%;瘤胃(含胃容物)重(平均3.81kg)占胃总重的72.43%;肠道总长为2708.86cm,是体长的25·71倍;小肠总长为1909.87cm,占肠道总长的70.50%;大肠总长为798.99cm,占肠道总长的29.50%。蒙原羚亚成体兼有精饲者和粗饲者的特征。 相似文献
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巴鲵幼体的犁骨齿为位于内鼻孔间略呈“八”形的两列,其前端超出内鼻孔甚多。变态过程中.随着犁骨的生长.其上的犁骨齿前部向内侧弯成直角或锐角.因此,巴鲵属具有小鲵科中与众皆不相同的犁骨齿列型式.研究比较了巴鲵属模式种施氏巴鲵与北鲵属模式种中亚北鲵的国内外各数十号标本.包括二者的模式标本.将该二属的属征加以订正.费梁等认为巴鲵属为北鲵属的异名.可能与他们观察北鲵的标本较少(3号)以及误以为北鲵非繁殖期成体“以水栖为主,均有唇褶”所致. 相似文献
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2022年5—7月,通过野外实地观察,在云南文山国家级自然保护区对蔡氏疣螈Tylototriton ziegleri的成体形态和胚胎发育进行研究,以期了解蔡氏疣螈的成体和胚胎的形态特征。结果显示,蔡氏疣螈雌雄两性的形态特征存在明显差异,雌性整体形态指标更大。雌性全长115.50~135.42 mm,雄性全长102.70~126.79 mm,两性异形指数为0.078。个体的全长、头体长、头长、头宽、吻长和腋至跨距在两性间的差异极显著(P<0.01),躯干长、眼间距、鼻间距、尾长和尾宽在两性间的差异显著(P≤0.05)。胚胎发育共有21个时期,历时(532.49±45.52) h。本研究通过对蔡氏疣螈形态和胚胎发育的详细观察,为有效保护该物种提供了科学依据。 相似文献
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大豆属Soja亚属种皮微形态特征的研究 总被引:1,自引:0,他引:1
采用扫描电镜对大豆属Soja亚属植物的种皮微形态特征进行了系统研究。结果表明,该亚属植物种皮微形态特征在种的水平上具有一定的分类学意义。 相似文献
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为了探讨爪鲵端脑的发育特点,充实比较神经生物学的研究资料,本文采用常规HE染色法,初步研究了成体和亚成体爪鲵端脑的组织学结构特征.结果 表明:爪鲵嗅球内细胞从外到内大致可分为6层结构,亚成体的细胞数量少于成体;成体爪鲵的侧脑室所占空间较大,脉络丛更为丰富,原始大脑皮层和原始海马都比亚成体发达,后者大脑内原始梨状区较为发达;隔区位于原始海马的下方,成体和亚成体都没有外侧隔核和内侧隔核之分,也没有外侧界沟作为原始梨状区和纹状体的分界,而在亚成体的侧脑室壁有内侧界沟区分原始海马和隔区,成体则没有;此外,爪鲵的纹状体属于古纹状体,杏仁核是位于第三脑室两侧的两个细胞团,端脑内细胞形态和大小分化较为单一.这些都表明亚成体爪鲵的端脑已大致具备了成体所具有的结构,并且也说明了爪鲵在两栖纲动物中属于较原始的种类,这在一定程度上填补了有关有尾两栖类神经系统资料以及神经发育资料的空白. 相似文献
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在扫描电镜下对药用植物苦丁茶(Ilex kudingcha C.J.Tseng)与4个近缘种的果皮微形态进行了观察。结果显示这些材料的果皮上均有气孔器存在,气孔圆形至椭圆形,气孔上拱盖表面近平滑或有蜡质碎片,拱盖内缘近平滑稀浅波状,外缘角质膜在气孔周围呈环形包着气孔。但各种间果皮的微形态特征具有较为明显的差异,有一定的分类鉴定意义,本研究结果表明扣树(I.kaushue S.Y.Hu)的果实有指状毛附属物,不支持与苦丁茶的合并。五棱苦丁茶(I.pentagona S.I.Chen,Y.X.Feng etC.F.Liang)的果皮特征与苦丁茶较近,但有明显差异,支持将其从苦丁茶中独立出建立一新种。 相似文献
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应用光学显微镜和扫描电子显微镜对29种野豌豆属植物叶表皮微形态特征进行了观察。结果显示:叶表皮细胞形状有无规则形和多边形2种,垂周壁式样有深波状、浅波状和平直-弓形;表皮角质层纹饰微形态多样,大多数植物叶片表面不具有腺毛或仅中脉有,少数植物叶片表面具腺毛;部分叶表皮上有柔毛,少数植物无毛。气孔器存在于上表皮、下表皮、或上下表皮均有,形状为椭圆形、卵圆形,均为无规则型。野豌豆属植物叶表皮的这些微形态特征,在属内组间没有明确的规律性,但可为探讨该属种间的分类学及亲缘关系提供依据。 相似文献
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幼年菲菊头蝠形态和声音发育 总被引:1,自引:0,他引:1
2006年5月31日—7月20日于桂林市郊积水洞对菲菊头蝠(Rhinolophus pusillus)幼蝠形态和叫声发育进行了研究。方差分析结果显示,幼蝠在出生后近3周内体重和前臂长增长迅速,随后增长速率变缓,且体重和前臂长增长与年龄均显著相关(年龄与体重:P=0.025;年龄与前臂长:P=0.042)。幼蝠叫声时程波动大,且均长于成年个体叫声时程,时程与年龄呈显著相关性。幼蝠在出生后3周内的叫声特征为频谱结构多样、频率波动大、谐波较多,在第3周后叫声多为FM-CF-FM叫声;幼蝠叫声第1谐波频率与年龄增长显著相关,而第二谐波频率与年龄相关性较弱;幼蝠在35天后主频率已经接近成年蝙蝠叫声频率;且前臂长与幼蝠叫声频率呈显著线性关系。 相似文献
15.
A. F. Sell 《Oecologia》2000,125(1):150-160
The presence of plankton predators may induce altered morphology in their potential prey. To date, the mechanism of induction
and adaptive value of such defensive responses have been examined in the laboratory. This study investigated the morphological
defense structures induced by the invertebrate predator Chaoborus in two coexisting Daphnia species, D. pulex and D. rosea, in the field. In Piscivore Lake (Gr?fenhain, Germany), continuous and intense biomanipulation had led to near elimination
of planktivorous fish and greatly increased abundances of Chaoborus (up to >10 larvae l–1). Here, the density of Chaoborus was manipulated within the lake by an enclosure/exclosure setup and resulting morphological responses of Daphnia spp. were investigated in situ. Three replicate enclosures (4.6 m3) contained no Chaoborus (predator exclusion bags), whereas Chaoborus entered three others at ambient densities (predator enclosures). In both species of Daphnia, formation of neckteeth and elongation of the tail spine were recorded in the predator enclosures, but not in the predator
exclusion treatments. Additionally, D. rosea responded to predator inclusion with an increase of the size at first reproduction. Despite the induced defense structures,
the presence of Chaoborus caused increased mortality of both Daphnia species. In addition, Chaoborus affected the coexistence of the two populations of Daphnia by causing higher relative mortality in D. rosea. Neckteeth formation was always more pronounced in D. pulex than in D. rosea of the same size. Neckteeth were induced specifically in vulnerably sized juvenile instars of D. pulex, but were not found in all vulnerable instars of D. rosea. In D. rosea, neckteeth were few or absent in the ephippial hatchlings, and neckteeth formation ceased before juveniles reached a body
size outside the range that larger larval stages of Chaoborus could ingest. This study provides the first experimental demonstration in the field of the inducibility of morphological
defense structures in Daphnia at ambient densities of Chaoborus larvae, and quantifies these in situ responses. This expands on earlier observations of a correlation between predator density in the field and the expression
of neckteeth in Daphnia. The term ”maximum size for neckteeth formation” (MSNF) is defined as the limit in body size above which no production of
neckteeth was evident. This limit was used to distinguish the size classes of Daphnia that show a sensitive response to Chaoborus kairomone. This new term may be used for further comparisons among species and among different types of predator-induced
responses as well as for the evaluation of the adaptive value of defense structures.
Received: 10 April 1999 / Accepted: 6 April 2000 相似文献
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利用光学显微镜对蹄盖蕨科15种植物的叶表皮形态特征进行观察和研究。结果表明:蹄盖蕨科15种植物的上、下表皮细胞均为无规则型,垂周壁为凹凸状或深波状;上表皮细胞长宽比在1.0~3.2之间,下表皮细胞长宽比在1.0~2.6之间;在这15种植物中共观察到6种气孔器类型,即极细胞型、腋下细胞型、聚合极细胞型、聚腋下细胞型、无规则四细胞型和无规则型,每种植物具有3~4种气孔器类型,气孔均为下生型,多呈椭圆形。气孔的长宽比在1.3~2.1之间;气孔密度在32~90个/mm2之间;气孔指数为17.7%~40.9%。依据上述叶表皮形态特征将15种蹄盖蕨科植物分为3类,即双盖蕨类、蹄盖蕨类和对囊蕨类。该研究在一定程度上支持Christenhusz分类系统对蹄盖蕨科的划分,为蹄盖蕨科植物的系统分类及演化研究提供基础资料。 相似文献
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朱砂根复合群形态性状的数量分析 总被引:1,自引:0,他引:1
朱砂根复合群—朱砂根(Ardisia crenata Sims)、红凉伞(A. crenata var. bicolor (E. Walker) C. Y. Wu C. Chen),和岭南紫金牛(A. linangensis C. M. Hu)之间存在一些过渡类型,很难依据少数几个关键性状对它们明确划分。本文运用E. Anderson的形象化散点图和柱状图的方法对全国14个省区135份标本的9个性状进行了分析,结果表明:岭南紫金牛应为独立的种,支持将红凉伞归并。 相似文献
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研究了普氏蹄蝠(Hipposideros pratti)不同状态(飞行、悬挂)下的回声定位声波特征、形态特征和生态特征(捕食策略、捕食地和食物类型).结果表明,普氏蹄蝠的回声定位声波为CFFM型,在不同状态下,主频率有一定的差异,飞行状态的主频率略低于悬挂状态,表明普氏蹄蝠是利用多谱勒补偿效应来适应飞行速度引起的主频率变化,以进行准确的定位和有效的捕食;同时飞行状态下声脉冲时间、声脉冲间隔时间及FM带宽略低于悬挂状态,而声脉冲重复率和能率环略高于悬挂状态,表明普氏蹄蝠在不同状态下利用不同特征的声波进行捕食.由回声定位声波推断和野外观察可知,普氏蹄蝠可能在树冠周围以盘旋方式(在昆虫高峰期)或以捕蝇器式(在昆虫高峰期之后)捕食中等偏大的振翅昆虫(如甲虫). 相似文献
19.
Antonella Bonacci Elvira Brunelli Emilio Sperone Sandro Tripepi 《Zoologischer Anzeiger》2008,247(1):47-54
The morphology and development of the larval oral apparatus of Rana dalmatina, Bombina variegata, Bufo bufo, and Bufo viridis are described and compared using scanning electron microscopy. The species show different arrangements of the mouthparts. The small oral apparatus of R. dalmatina larvae has three labial tooth rows on the upper labium, while there are four tooth rows on the lower labium with a medial gap in row proximal to the mouth. The margins of the oral apparatus are defined by papillae that encircle the lower labium. B. variegata tadpoles have two upper labial tooth rows and three lower labial tooth rows that are uninterrupted, unlike the ones of R. dalmatina. The mouth is encircled by papillae that are larger than those of R. dalmatina. The oral discs of tadpoles of both B. bufo and B. viridis are similar. They are defined by two upper labial tooth rows (the second of which is interrupted by a medial gap) and by three lower tooth rows that differ in lengths in the two Bufo species. Both species develop papillae on the mouth angles and in two rows on the upper labium. Some morphological differences among the oral discs of R. dalmatina, B. variegata, B. bufo, and B. viridis tadpoles can be attributed to phylogenetic differences, but most can be related to their varying feeding habits and/or to their dietary specializations. 相似文献
20.
Martin O'brien Damian Egan Padraig O'kiely Patrick D. Forristal Fiona M. Doohan Hubert T. Fuller 《Mycological Research》2008,112(8):921-932
The morphological and molecular features of Penicillium roqueforti and P. paneum isolated from baled grass silage were characterised. A total of 315 isolates were investigated, comprising 237 P. roqueforti and 78 P. paneum isolates randomly selected from more than 900 Penicillium colonies cultured from bales. The macromorphological features of both species broadly agreed with the literature, but the micromorphological features differed in some respects. When observed using SEM, P. roqueforti and P. paneum had finely roughened conidia, and conidiophores, phialides and conidia of P. paneum were each larger than those of P. roqueforti. Based on the phylogenetic analysis of partial sequences of β-tubulin and acetyl co-enzyme A (CoA) synthetase genes, P. roqueforti and P. paneum isolates were found to be monophyletic species. 相似文献