974 resultados para Taxonomic impediment


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本论文对葛属(Pueraria DC.)进行了形态学、解剖学及植物地理学研究,重点分析了小叶、托叶、花序及花的形态变异规律。首次发现葛属生长习性和种皮纹饰特征在组的划分上具有重要的分类学意义,支持前人运用托叶着生方式、花序类型及每节簇生花的数目等特征划分组的观点。首次在光学显微镜下对葛属植物14种1变种叶表皮性状做了较为全面、深入的观察,发现葛属叶表皮细胞的形状、垂周壁的式样以及气孔大小有一定分类学意义,为葛属的分类修订提供了新资料。首次应用电子扫描显微镜观察了葛属10种1变种和2个外类群广西土黄芪Nogra guangxiensis C. F. Wei和琼豆Teyleria koordersii (Backer ex Koord.-Schum.) Backer的种皮纹饰特征,发现葛属的种皮纹饰有网纹型、断棱型、复网纹型和锐棱型等4种类型,他们与托叶的着生方式具有一定的关联性。托叶背着的类群为网纹型,其中采自中国和越南不同居群的山野葛Pueraria montana (Lour.) Merr.种皮次级纹饰有差别,这显示山野葛分化比较活跃。托叶基着的三裂叶野葛P. phaseoloides (Roxb.) Benth.、大花三裂叶野葛P. phaseoloides (Roxb.) Benth. var. javanica (Benth.) Baker、苦葛P. peduncularis (Graham ex Benth.) Benth.以及云南野葛P. yunnanensis Franch.的种皮纹饰为断棱形,小花野葛P. stricta Kurz种皮纹饰为复网纹型,喜玛拉雅葛藤P. wallichii DC.种皮纹饰为锐棱型。依据种皮纹饰推断,喜玛拉雅葛藤最原始,黄毛葛藤P. calycina Franch.最进化,与形态学特征演化方向相吻合。广西土黄芪种皮纹饰为网纹型,琼豆种皮纹饰为复网纹型,表明它们与葛属亲缘关系较近。这与形态学和分子证据相吻合。本文首次运用广义线形模型(GLM)结合地理信息系统(GIS)对葛属现有地理分布、潜在分布及50年后潜在分布进行了分析。所预测的潜在分布范围与观察到的地理分布范围一致,说明对特化的气候忍耐性是限制葛属物种地理分布的主要因素。温度、降水和海拔高度对葛属地理分布限制作用比较大。未来潜在分布预测显示葛属有向南、北扩散的趋势。 作者在研究了四千余份腊叶标本及野外形态考察的基础上,结合叶表皮及种皮纹饰资料,确认葛属分为3组,共19种3变种。其中,对Sect. Breviramulae Maesen ex Z. F. Le & X. Y. Zhu进行了合格发表,运用形态学、解剖学及种皮纹饰资料恢复了云南野葛种的地位,并为其指定了后选模式,P. pulcherrima (Koord.-Schum.) Merr. ex Koord.-Schum.正确的学名为P. sericans Schum.,对4个名称进行了归并。本文还给出了组和种的检索表、葛属各个种的形态描述、地理分布图及模式标本照片。

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钻地风属(Schizophragma Siebold & Zucc.)和冠盖藤属(Pileostegia Hook. f. & Thomson)隶属于虎耳草科绣球花亚科绣球花族植物,分布于东亚。本论文对钻地风属和冠盖藤属进行了全面的分类学研究:重点分析了钻地风属和冠盖藤属各形态性状的变异式样,确定了二属的性状变异范围;在光学显微镜下,对钻地风属中6种5变种和冠盖藤属中2种共130份材料的叶表皮特征进行了深入、全面的观察和研究;并对二属的叶脉序特征进行了研究。结果显示,苞片存在与否、不育花存在与否、花瓣顶端是否联合、蒴果和种子的形状、叶片质地、生长习性、表皮细胞垂周壁加厚与否、气孔器分布、类型、气孔大小、保卫细胞轮廓、外拱盖是否双层、二级脉、三级脉、高级脉及网眼等特征在属的水平上具有重要的分类学意义,这些性状特征支持将钻地风属和冠盖藤属作为两个独立的属处理。根据形态性状及叶脉序特征推测,冠盖藤属较原始,钻地风属较进化。在钻地风属中,叶片毛被的有无及类型、叶片形状和叶缘的形状等特征可作为可靠的分种依据;叶表皮特征在种及种下等级具有重要的分类学意义;叶脉序多呈现环节曲行羽状脉式样,二级脉具分枝,在种间存在细微差别。根据形态性状及叶脉序特征推测,厚叶钻地风S. crassum Hand.-Mazz.和白背钻地风S. hypoglaucum Rehder可能为钻地风属中较原始的类群,秦榛钻地风S. corylifolium Chun和绣球钻地风S. hydrangeoides Siebold & Zucc.可能较进化。在冠盖藤属中,叶片毛被的有无及类型、叶片形状等特征可作为可靠的分种依据;该属中叶表皮特征相似,2个种间叶表皮特征无差异;叶脉序多呈现环节曲行羽状脉式样,二级脉无分枝,在种间差异极小。 作者在研究了近2000份腊叶标本的基础上,结合叶表皮特征和叶脉序特征,认为钻地风属和冠盖藤属为两个独立的属。首次对钻地风属和冠盖藤属进行了世界性的分类学修订,确认钻地风属含7个种、5个变种,冠盖藤属含2个种。对钻地风属中的5个名称和冠盖藤属中的2个名称进行了归并;为钻地风属中的1个名称和冠盖藤属中的2个名称指定了后选模式;发现被命名为维西钻地风S. crassum Hand.-Mazz. var. hsitaoianum (Chun) C. F. Wei的类群其正确名称为S. crassum Hand.-Mazz. var. ellipticum J. Anthony;恢复了变种小粉绿钻地风S. integrifolium Oliv. var. minus Rehder;重新界定了白背钻地风和小粉绿钻地风的变异范围,澄清了中国文献中记载的粉绿钻地风S. integrifolium Oliv. var. glaucescens Rehder长期存在的名实混乱问题。本论文对各个分类群进行了详细的形态描述,给出了分种检索表,并附分布资料及地理分布图。

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A survey of the larval and juvenile fishes associated with the pelagic Sargassum habitat in the South Atlantic Bight and adjacent western Atlantic Ocean was conducted from July 1991 through March 1993. Fishes representing 104 taxonomic categories were identified, including reef fishes, coastal demersal, coastal pelagic, epipelagic and mesopelagic species. The most important families were Balistidae and Carangidae, each represented by 15 species. Species composition, species diversity and abundance varied both seasonally and regionally. Diversity was highest during spring through fall over the outer continental shelf and in the Gulf Stream. Abundance decreased from spring through winter and from the continental shelf into offshore waters. The numbers of fishes and fish biomass were found to be positively correlated with the wet weight of algae in most cases examined. The results of this study will be useful to fisheries managers assessing the potential impacts of commercial Sargassum harvesting in the region.

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山黑豆属Dumasia DC.隶属于豆科、菜豆族、大豆亚族,广泛分布于亚洲、非洲东南部的热带、亚热带地区以及大洋洲的巴布亚新几内亚地区,其中大多数种在我国均有分布。该属形态变异复杂,命名混乱,缺乏世界性的系统分类学研究基础。基于这样的背景,本论文通过开展形态学、解剖学、细胞学及孢粉学等方面的综合研究工作,对该属进行了全面的分类修订,对属内种间关系及地理分布格局进行了分析和探讨,结果如下: 1、形态学 在研究了大量腊叶标本和进行了野外考察的基础上,对山黑豆属植物的形态性状的变异式样进行了分析。该属植物的根系形态较为多样,可以作为划分种的辅助形状,分为有主根类型 (2个种,心叶山黑豆D. cordifolia Benth. ex Baker和柔毛山黑豆D. villosa DC.) 和无主根类型 (5个种,云南山黑豆D. yunnanensis Y. T. Wei & S. K. Lee、小鸡藤D. forrestii Diels、硬毛山黑豆D. hirsuta Craib、山黑豆D. truncata Siebold & Zucc.和长圆叶山黑豆D. henryi (Hemsl.) B. Pan & X. Y. Zhu);该属几乎全为多年生缠绕草本,只有柔毛山黑豆为半灌木,因此可能是该属中较原始的种类;该属植物的萼筒管状、筒口斜截形及花柱细长且弯曲处膨大等独特的解剖结构是区别该属其它近缘属的重要性状;花序和复叶的长度及荚果内种子数目变异幅度极大,缺乏稳定性,并非好的分类性状。 2、解剖学 应用光学显微镜,首次对山黑豆属7种植物 (心叶山黑豆、柔毛山黑豆、云南山黑豆、小鸡藤、硬毛山黑豆、山黑豆和长圆叶山黑豆) 的叶表皮进行了观察。结果表明,该属植物叶表皮细胞均呈不规则形,垂周壁为波状,气孔器类型以平列型为主。心叶山黑豆、柔毛山黑豆和云南山黑豆上表皮细胞垂周壁呈深波状;小鸡藤、长圆叶山黑豆、山黑豆和硬毛山黑豆上表皮细胞垂周壁呈浅波状。在一定程度上,上表皮细胞垂周壁的形态反映了山黑豆属种间的近缘关系。 3、细胞学 首次报道了山黑豆属3个种 (云南山黑豆、小鸡藤和硬毛山黑豆) 的染 色体数目,它们均为2n=20。在已报道染色体的植物种类中 (共计6种),仅心叶山黑豆染色体数目为2n=22,其余5种 (柔毛山黑豆、山黑豆、云南山黑豆、小鸡藤和硬毛山黑豆) 染色体数目均为2n=20。与大豆亚族大多数属染色体数目为2n=22相比较,心叶山黑豆可能是该属中较为原始的种。 4、孢粉学 在光学显微镜下,对该属7种植物 (心叶山黑豆、柔毛山黑豆、云南山黑豆、小鸡藤、硬毛山黑豆、山黑豆和长圆叶山黑豆) 的花粉进行了观察,结果表明:该属植物为三角形6孔花粉,极轴短,每个角的萌发孔由一对小孔组成;外壁具网纹,网脊粗,网眼不规则。柔毛山黑豆和小鸡藤极面的网脊几乎不断裂;心叶山黑豆、云南山黑豆、硬毛山黑豆、山黑豆和长圆叶山黑豆极面的网脊断裂较多。外壁的纹饰在一定程度上反映了该属植物的近缘关系。 5、地理分布格局 该属植物主要分布在中国南部和西南,只有柔毛山黑豆分布到非洲和大洋洲。研究结果表明,具主根的2个种 (心叶山黑豆和柔毛山黑豆) 主要分布在中国西南部,其分布区域相互重叠;而无主根的5个种 (云南山黑豆、小鸡藤、硬毛山黑豆、山黑豆和长圆叶山黑豆) 由中国西南部向东到日本、韩国都有分布,分布区域几乎不重叠。本研究认为:有主根的心叶山黑豆和柔毛山黑豆可能代表了该属的原始类群;有主根类群衍生出其余无主根类型的各种,并由中国西南扩散到其他地区。 综合以上资料,本研究对山黑豆属进行了分类修订,认为该属含8种、1亚种及2变种,其中建立新组合1个,归并6个类群,并指定了4个后选模式。另外,本研究同时提供了该属植物的检索表、种的形态描述和插图以及地理分布图等信息。

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通过野外采集和观察,标本鉴定和实验研究,从植物形态学,叶柄和根状茎的解剖,叶表皮的显微观察,和孢子形态的扫描电镜观察等方面进行研究与分析,对中国瓦韦属(除薄叶组)进行了分类学修订研究。 1. 形态性状分析 研究了国内外重要标本馆的大量瓦韦属植物标本,通过对一些重要的形态性状的观察和分析,判定其变异规律及分类学意义。根状茎上的鳞片和孢子囊上的隔丝的形状和网眼结构是瓦韦属属下分类和种的划分的最主要的形态学性状。其它特征如孢子囊群着生的位置、中脉的颜色、根状茎直立或横走等在种内也具有一定的稳定性,可以帮助种的划分和鉴定。因此,在对瓦韦属植物进行分类时要结合几个相关性状而不是单一的性状进行分类。 2. 叶柄和根状茎的解剖 对瓦韦属(除薄叶组)49 个种的叶柄和根状茎进行解剖观察,发现叶柄中维管束的条数一般为1--7 条不等,排成一字形、三角形或半圆形。两根粗的维管束排列在腹面,较细的维管束排列在背面。叶柄中没有厚壁组织,但是在叶柄和根状茎的连接部位叶足处有厚壁组织的存在。根状茎横切面观察显示除了维管束外还有厚壁组织的存在,在常绿种内厚壁组织较多,落叶类型中厚壁组织较少。 3. 叶表皮形态 观察了瓦韦属51 个种的叶表皮形态和结构,发现该性状对于属下划分具有一定的系统学意义,也有助于疑难物种的鉴别。瓦韦属植物的叶表皮细胞形状通常为多边形、不规则;垂周壁式样为波状和浅波状;气孔器类型比较复杂,在所观察的类群中,气孔器都分布在下表皮上,极细胞型Polocytic type,共环极细胞型Copolocytic type ,腋下细胞型Axillocytic type ,聚腋下细胞型Coaxillocytic 是最常见的类型,不规则型Anomocytic type ,不规则四细胞型Anomotetracytic type,不等细胞型Anisocytic type,辐射状细胞型Actinocytic type 和双环不等四细胞型Amphicycloanisocytic type 也存在于瓦韦属的叶表皮中。属下同一个组的叶表皮特征近似,不同的组具有一定的差别。 4. 孢子形态 在扫描电镜下对瓦韦属50 个种的孢子形态进行了观察。瓦韦属的孢子两侧对称,极面观为椭圆形,赤道面观为肾形、豆形或半圆形。孢子的表面纹饰可以分为6 类,分别是光滑、颗粒状、瘤状、皱状、波状以及疣状的纹饰。瓦韦属的孢子周壁较薄,纹饰由外壁组成。孢子形态具有重要的系统学意义,可以为属下分类提供可靠的证据,对形态近似的物种的划分也有重要参考价值。 通过对大量标本的研究,以及模式标本的考证,结合野外居群观察,综合分析有关分类学资料,主要依据比较稳定的微观性状,对瓦韦属植物进行了新的分类学修订。结果承认中国瓦韦属(除薄叶组)有37 种,可以分为5 个组,有3 个名称被首次处理为异名,另有2 个种暂时存疑。

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毛茛科(Ranunculaceae )铁线莲属(Clematis L.)长瓣铁线莲组(Sect. Atragene) 植物全世界约有14-18 种,我国约有6 种,广泛分布于北温带的高山上。该组植物由于外部形态变异大,种间或种下划分十分困难,目前已发表的种及种下分类群名称多达130 余个,名称使用较为混乱,组内系统关系尚存争议。本文通过文献考证、标本研究、野外观察及形态性状统计分析的综合研究,对长瓣铁线莲组进行了全面的分类学修订,结果如下: 1、性状分析 深入研究了1000 余号该组植物标本的形态性状变异式样、范围及其相关性,发现复叶类型、小叶大小、萼片毛被和质地、萼片脉突出与否、退化雄蕊长度等是较为稳定的分种性状。生长习性、萼片颜色、萼片边缘是否具短绒毛带、退化雄蕊形状等对种下划分具有重要的意义。 2、分类学处理 1)根据该组植物的萼片和退化雄蕊的特征和演化趋势,建立了5 个新系:Ser. 1. Occidentales、Ser. 2. Alpinae、Ser. 3. Koreanae 、Ser.4. Tomentosae 和Ser. 5. Macropetalae 。 2)对长期以来分类上争议很大,且分类十分困难的类群作出以下新的处理:把C. sibirica 和C. ochotensis 作为C. alpina 的亚种;把日本的C. fusijamana 和C. fauriei 降级为半钟铁线莲C. alpina ssp. ochotensis 的变种;把伊犁铁线莲C. iliensis 降级为西伯利亚铁线莲C. alpina ssp. sibirica 的变种;把C. chiisanensis 降级为朝鲜铁线莲C. koreana 的变种;把紫红花长瓣铁线莲C. macropetala var. punicoflora 和石生长瓣铁线莲C. macropetala var. rupestris 处理为长瓣铁线莲C. macropetala 的异名;把C. dianae 归并入白色长瓣铁线莲C. macropetala var. albiflora;支持长白铁线莲C. nobilis 作为一个独立的种。此外,还新指定了5 个名称的后选模式;纠正了前人对中国C. subtriternata 的鉴定错误。 3)确认该组植物有9 种2 亚种和9 变种(包括3 新等级),给出了各个分类群详细的文献引证、描述、生境、地理分布、标本引证和外部形态图,并编写了组下分系和分种检索表。认为亚洲东北部是本组植物分布的多样性中心。 3、形态性状演化趋势和各系的亲缘关系 探讨了该组植物形态性状演化的趋势和新建立的5 个系的亲缘关系,提出:退化雄蕊可能由外部雄蕊演化而来,并沿两条路线演化发展:其一是退化雄蕊伸长,与萼片近等长或长于萼片,顶端渐狭,呈披针形;其二是退化雄蕊不伸长,与雄蕊近等长,上部加宽,顶端由钝形、圆形发展至微凹,呈匙形。萼片演化的趋势可能由质地薄到质地厚,萼片脉由不凸出到3 条脉凸出。由此推测北美洲类群Ser. Occidentales 可能是本组的原始类群;Ser. Macropetalae 可能是退化雄蕊在第一条演化路线上最进化的类群;Ser. Alpinae 和Ser. Koreanae 之间亲缘关系较近;Ser. Tomentosae 的系统位置尚未确定。

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本论文包括两部分的内容,第一部分是秦岭苔类植物的区系研究,第二部分是中国剪叶苔属Herbertus的分类学修订。 秦岭位于我国的中部,东经104º30´~112º52´,北纬32º50´~34º45´N,约76 500 km2。它主要位于陕西省的南部地区,并包括了河南、甘肃和湖北的部分县、市。秦岭的最高峰是太白山,海拔3 767米。秦岭是长江和黄河的分水岭,也是我国温带和亚热带气候的过渡地带。 本研究包含了对自19世纪开始对秦岭苔藓植物的主要采集活动的回顾,和截止2008年以来对秦岭苔类和角苔类植物报道的总结和分析,且首次给出了一份秦岭地区详细的苔类植物的名录,并包括了各个种在秦岭地区的详细分布。根据目前的研究,现已知秦岭的苔类植物有226种(包括种下单位,以下同),其中角苔纲1科3属6种,苔纲30科59属220种;提出了1个新异名:Radula constricta Steph.被处理为Radula lindenbergiana Gottsche var. atypa Massalongo的异名;并提出了1个新组合Metzgeria pubescens var. kinabaluensis (Kuwah) F.X. Li & Y. Jia;发现秦岭新分布的苔类有78种。根据种数,秦岭地区苔类的优势科为光萼苔科(34种),其次为耳叶苔科(23种),裂叶苔科(23种)和羽苔科(19种)。 通过对这些种地理成分的统计,发现秦岭苔类的地理成分以北温带成分为主,占35.05%;其次是东亚成分占到31.78%,这两种地理成分在秦岭占了很大比例,高达66.83%。热带成分相对较少,有22种,占到10.29%。对于苔类来说,中国特有成分在秦岭地区较多,已知有34种,占到15.89%。说明秦岭地区苔类地理成分以温带为主,热带成分占少量比例,且秦岭地区的特有性也比较高。 文章第二部分是对中国剪叶苔属Herbertus S. Gray的分类学修订。剪叶苔属隶属于剪叶苔科,是一个古老而自然的类群,广泛分布于热带和南北温带地区。剪叶苔属植物由于其叶横生或近于横生,侧叶2裂,腹叶2裂或部分不对称3裂,并具假肋,叶细胞具大的三角体而明显区别于苔类的其它属。虽然这个属的概念比较清楚,但在属内种间的划分上存在较大的问题,是苔类中分类较混乱的一个类群。剪叶苔属种的概念多基于叶片形态,包括裂瓣的顶端细胞和假肋的形态及叶基盘边缘附属物的形态。但这些形态特征具很大的可塑性,性状不稳定,造成该属种的概念很模糊。目前全世界剪叶苔属约100余种。中国剪叶苔属的种类尚不确定,《中国苔藓志》中报道了中国有25种l亚种,但Juslen在2006年对亚洲剪叶苔属的修订中,提到中国分布的仅有6种。二者的研究中都存在有一些疏漏和不足之处,对有些种还有争议;且他们的研究中引证的标本都很少,不能全面反映中国剪叶苔属的种类和分布情况。 本研究着手于中国的剪叶苔属,从模式标本入手,从模式标本入手,结合对前人文献中引证标本的查阅,并检视了全国各大标本馆收藏的大量该属的普通标本,对于分类归并上有争议的种,采用扫描电镜和分子生物学的手段进行实验性的研究,对中国的剪叶苔属进行一个全面系统的分类学修订。期望通过本研究,明确中国剪叶苔属的种类和分布情况,为东亚乃至世界剪叶苔属的分类修订提供一份翔实的资料。共查阅了剪叶苔属26个种的模式标本,并检视了中科院北京植物研究所、华南植物园和深圳仙湖植物园馆藏的大量该属植物标本,约600余份。 通过本研究,提出2个新异名:将H. buchii Juslén和H. longispinus var calvs Massalongo处理为H. dicranus (Taylor) Trevis.;将樱井剪叶苔H. sakuraii (Warnst.) S. Hatt.(原并入H. dicranus)和H. minimus Horik.(原并入H. dicranus)重新提出;发现1个中国新分布:H. setigerus (Steph.) H. A. Mill.;确认中国的剪叶苔属17种1亚种:剪叶苔H. aduncus (Dicks.) Gray,剪叶苔纤细亚种H. aduncus subsp. tenuis (A. Evans) H. A. Mill.et E. B. Bohrer,H. armitanus (Steph.) H. A. Mill.,南亚剪叶苔H. ceylanicus (Steph.) Abeyw.,长角剪叶苔H. dicranus (Taylor) Trevis.,高氏剪叶苔H. gaochienii Fu,广东剪叶苔H. guangdongii P.J. Lin & Piippo,卵叶剪叶苔H. herpocladioides Scott. et. Miller,红枝剪叶苔H. huerlimannii Miller,细指剪叶苔H. kurzii (Steph.) H. A. Mill.,长肋剪叶苔H. longifissus Steph.,长刺剪叶苔H. longispinus Jack et Steph.,H. minimus Horik.,长茎剪叶苔H. parisii (Steph.) H. A. Mill.,多枝剪叶苔H. ramosus (Steph.) H. A. Mill.,樱井剪叶苔H. sakuraii (Warnst.) S. Hatt.,短叶剪叶苔H. sendtneri (Nees) Lindb.和H. setigerus (Steph.) H. A. Mill.。本研究还在扫描电镜下观察了H. armitanus、长角剪叶苔H. dicranus和多枝剪叶苔H. ramosus的孢子形态。对于剪叶苔属的修订,还需要更多模式标本的借阅,随着研究深入,剪叶苔属的种类可能会有大量的减少,中国剪叶苔属的种类也将会有一定的减少。

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Remotely operated vehicle (ROV) surveys were conducted from NOAA’s state-of-the-art Fisheries Survey Vessel (FSV) Bell M. Shimada during a six-day transit November 1-5, 2010 between San Diego, CA and Seattle, WA. The objective of this survey was to locate and characterize deep-sea coral and sponge ecosystems at several recommended sites in support of NOAA’s Coral Reef Conservation Program. Deep-sea corals and sponges were photographed and collected whenever possible using the Southwest Fisheries Science Center’s (SWFSC) Phantom ROV ‘Sebastes’ (Fig. 1). The surveyed sites were recommended by National Marine Sanctuary (NMS) scientists at Monterey Bay NMS, Gulf of the Farallones NMS, and Olympic Coast NMS (Fig. 2). The specific sites were: Sur Canyon, The Football, Coquille Bank, and Olympic Coast NMS. During each dive, the ROV collected digital still images, video, navigation, and along-track conductivity-temperature-depth (CTD), and optode data. Video and high-resolution photographs were used to quantify abundance of corals, sponges, and associated fishes and invertebrates to the lowest practicable taxonomic level, and also to classify the seabed by substrate type. A reference laser system was used to quantify area searched and estimate the density of benthic fauna.

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Contemporary in-depth sequencing of environmental samples has provided novel insights into microbial community structures, revealing that their diversity had been previously underestimated. Communities in marine environments are commonly composed of a few dominant taxa and a high number of taxonomically diverse, low-abundance organisms. However, studying the roles and genomic information of these “rare” organisms remains challenging, because little is known about their ecological niches and the environmental conditions to which they respond. Given the current threat to coral reef ecosystems, we investigated the potential of corals to provide highly specialized habitats for bacterial taxa including those that are rarely detected or absent in surrounding reef waters. The analysis of more than 350,000 small subunit ribosomal RNA (16S rRNA) sequence tags and almost 2,000 nearly full-length 16S rRNA gene sequences revealed that rare seawater biosphere members are highly abundant or even dominant in diverse Caribbean corals. Closely related corals (in the same genus/family) harbored similar bacterial communities. At higher taxonomic levels, however, the similarities of these communities did not correlate with the phylogenetic relationships among corals, opening novel questions about the evolutionary stability of coral-microbial associations. Large proportions of OTUs (28.7–49.1%) were unique to the coral species of origin. Analysis of the most dominant ribotypes suggests that many uncovered bacterial taxa exist in coral habitats and await future exploration. Our results indicate that coral species, and by extension other animal hosts, act as specialized habitats of otherwise rare microbes in marine ecosystems. Here, deep sequencing provided insights into coral microbiota at an unparalleled resolution and revealed that corals harbor many bacterial taxa previously not known. Given that two of the coral species investigated are listed as threatened under the U.S. Endangered Species Act, our results add an important microbial diversity-based perspective to the significance of conserving coral reefs.

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The U.S. Marine Mammal Protection Act requires that the abundance of marine mammals in U.S. waters be assessed. Because this requirement had not been met for a large portion of the North Atlantic Ocean (U.S. waters south of Maryland), a ship-based, line-transect survey was conducted with a 68 m research ship between Maryland (38.00°N) and central Florida (28.00°N) from the 10-m isobath to the boundary of the U.S. Exclusive Economic Zone. The study area (573,000 km2) was surveyed between 8 July and 17 August 1998. Minimum abundance estimates were based on 4163 km of effort and 217 sightings of at least 13 cetacean species and other taxonomic categories. The most commonly sighted species (number of groups) were bottlenose dolphins, Tursiops truncatus (38); sperm whales, Physeter macrocephalus (29); Atlantic spotted dolphins, Stenella frontalis (28); and Risso’s dolphins, Grampus griseus (22). The most abundant species (abundance; coeffi cient of variation) were Atlantic spotted dolphins (14,438; 0.63); bottlenose dolphins (13,085; 0.40); pantropical spotted dolphins, S. attenuate (12,747; 0.56); striped dolphins, S. coeruleoalba (10,225; 0.91); and Risso’s dolphins (9533; 0.50). The abundance estimate for the Clymene dolphin, S. clymene (6086; 0.93), is the first for the U.S. Atlantic Ocean. Sperm whales were the most abundant large whale (1181; 0.51). Abundances for other species or taxonomic categories ranged from 20 to 5109. There were an estimated 77,139 (0.23) cetaceans in the study area. Bottlenose dolphins and Atlantic spotted dolphins were encountered primarily in continental shelf (<200 m) and continental slope waters (200−2000 m). All other species were generally sighted in oceanic waters (>200 m). The distribution of some species varied north to south. Striped dolphins, Clymene dolphins, and sperm whales were sighted primarily in the northern part of the study area; whereas pantropical spotted dolphins were sighted primarily in the southern portion.

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Light traps and channel nets are fixed-position devices that involve active and passive sampling, respectively, in the collection of settlement-stage larvae of coral-reef fishes. We compared the abundance, taxonomic composition, and size of such larvae caught by each device deployed simultaneously near two sites that differed substantially in current velocity. Light traps were more selective taxonomically, and the two sampling devices differed significantly in the abundance but not size of taxa caught. Most importantly, light traps and channel nets differed greatly in their catch efficiency between sites: light traps were ineffective in collecting larvae at the relatively high-current site, and channel nets were less efficient in collecting larvae at the low-current site. Use of only one of these sampling methods would clearly result in biased and inaccurate estimates of the spatial variation in larval abundance among locations that differ in current velocity. When selecting a larval sampling device, one must consider not only how well a particular taxon may be represented, but also the environmental conditions under which the device will be deployed.

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The phytoplankton species composition and abundance in Ogun River, Ogun state, Southwest Nigeria was studied for a period of seven months (December, 2011 - June, 2012), a total of forty-one genera belonging to five taxonomic groups were recorded from Ogun River. The phytoplankton species composition was surpassed by Chrysophyta with 15 species consisting of 36.6% followed by Chlorophyta with 14 consisting of 34.1%. This was followed by Cyanophyta (7 species) consisting of 17.1%, Euglenophyta with 3 species consisting of 7.3% and Pyrrophyta with 2 species consisting 4.92%. Cyanophyta was the highest in abundance consisting of 41% while the lowest in abundance was Pyrrophyta consisting of 1.5%. The low nature of phytoplankton abundance and diversity observed in this study must have been caused by the polluted nature of the water due to the anthropogenic activities carried out around its shores The dominance of Cyanophyta in this river is similar to findings from Lake Victoria, Lake Bishoftu, Lake Chaohu and the temple pond of Thirupour.

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Investigation on the species composition and abundance of zooplankton in Ogun River, Abeokuta, Ogun state, Southwestern Nigeria was carried out for a period of seven months (December, 2011-June, 2012), Using hand trawling method, 55 µm mesh size plankton net was trawled horizontally ten times to capture zooplankton. The zooplankton samples were put into properly labeled plastic containers and preserved in 4% formalin solution. A total of sixteen genera from five taxonomic groups were recorded from Ogun River. Cladocera predominated both in terms of species composition and abundance. Five species of Cladocera was recorded consisting of 31.25%. Protozoa and Rotifera recorded four species each consisting of 25%. Copepoda recorded two species consisting of 12.5%, and Ostracoda with one species consisting of 6.25%. The low nature of zooplankton abundance and species composition observed in this study must have been caused by the polluted nature of the water due to the anthropogenic activities carried out around its shores The dominance of Cladocera in this river is similar to findings from River Echara and River Imo, Southeastern Nigeria.

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A taxonomic key is presented of the Stomatopoda (family Gonodactylidae) of the IndoWest Pacific Region.

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Morphology and taxonomy of four species of Ulva i.e. U. anandii Amjad et Shameel sp. nov., U. bifrons Ardre, U. saifullahii Amjad et Shameel sp. nov. and U. taeniata (Setchell) et Gardner were described for the first time from Pakistan. Their anatomy has been investigated in detail and compared with the allied species. A taxonomic comment has been written on U. grandis Saifullah et Nizamuddin.