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1.
Saito Y  Okuyama M 《Zoological science》2003,20(9):1153-1161
The morphology and life history of a strange and unidentified botryllid ascidian were investigated. This ascidian was first collected from the stony shore of Ebisu Island in Shimoda, a city on Izu peninsula in central Japan. Unlike other botryllid ascidians, whose colonies are flat and smooth, this ascidian's colonies are rugged. In each colony, zooids are arranged into several oval systems, each of which has a thick part containing zooids and very thin parts that do not. The arrangement of ovary and testis in this species is the same as in other species of the genus Botryllus; the ovary is situated anterior to the testis. The embryo of this ascidian develops in the peribranchial cavity of its mother zooid without any brooding organs, as is the case with Botryllus scalaris and Botryllus puniceus. Meanwhile, the results of cut colony assay experiments did not show the existence of colony specificity in this ascidian. Even when two syngeneic colonies were brought into contact at their growing edges, none fused together. On the other hand, when two colonies were brought into contact with each other at their cut surfaces, they always fused into a single colony, regardless of their origin. Therefore, this species may be the only species that lacks colony specificity among the botryllids studied so far.  相似文献   

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The morphology and life history of a new species of the genus Botryllus belonging to the family Botryllidae are described in detail. This ascidian was collected from the stony shore in the cove near Shimoda Marine Research Center, University of Tsukuba (Shimoda, Shizuoka Prefecture, Japan). The ascidian colony was easily distinguished from colonies of other botryllids because it was very thin and bright pink in color. The arrangement of ovary and testis in this ascidian was the same as that in other species of the genus Botryllus. This ascidian was prolific, with 1-5 embryos on each side of a zooid, and the embryos of this ascidian developed in the peribranchial cavity without any brooding organs as in Botryllus scalaris. We observed the processes and features of the allorecognition reaction in colony specificity and found that allorejection occurred after fusion of the vascular system between two incompatible colonies. This manner of allorejection is also shown in B. scalaris and Botryllus delicatus; however, the reaction speed of allorejection is faster than that of B. delicatus and similar to that of B. scalaris. These results indicate that this ascidian might be closely related to B. scalaris.  相似文献   

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中国乳菇属的研究III一个采自西藏的新种   总被引:1,自引:0,他引:1  
报道了一个采自西藏的乳菇属新种Lactarius imbricatus(翘鳞乳菇)。文中提供了拉丁文描述、英文描述并附线条图及孢子的电镜扫描照片。标本保存于中国科学院昆明植物所隐花植物标本馆(HKAS)和中国科学院微生物研究所菌物标本馆(HMAS)。  相似文献   

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An examination of the external morphology of a recent collection from Araracuara, Colombia, has suggested that the plant belongs to the primarily Old World family Dipterocarpaceae. A study of the wood, bark, and pith anatomy of this new taxon,Pseudomonotes tropenbosii Londoño, Alvarez & Forero, was undertaken to help confirm its systematic affinities. Comparisons ofPseudomonotes with data from the literature and reference wood slides, coupled with the use of computer-aided identification keys, support the view that its closest relationships probably are within the family Dipterocarpaceae. Detailed anatomical comparisons have revealed thatPseudomonotes' relationships are most likely to be with the subfamily Monotoideae, comprised of the African generaMonotes A. DC. andMarquesia Gilg.  相似文献   

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Immunocytochemical methods were used to study the presence and distribution of IL-1-alpha- and TNF-alpha-like molecules in the hemocytes of the colonial ascidian Botryllus schlosseri. Only a few unstimulated hemocytes were positive to both the antibodies used. When the hemocytes were stimulated with either mannan or phorbol 12-mono-myristate, the phagocytes were not significantly changed in their number, staining intensity, or cell morphology. In contrast, stimulated morula cells were intensely labeled, indicating that these cells play an important immunomodulatory role.  相似文献   

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朱华  王洪  李保贵   《广西植物》1999,19(4):337-338
勐腊锡叶藤 新种 图1TetraceraxuiH-ZhuetH-Wang,sp-nov-pl-AffinisT-scandenti(Linn-)Merr-sedinflorescentiisminoribus,paucifloris,sepalismajoribus1-5cmlongisinstatufructuextusdensevillosis,staminibus1cmlongis,capsulismajoribushirsutis,1-5~2cmlongis,1-2~1-5cmlati…  相似文献   

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Reproductive organs of four botryllid ascidians, Botryllus primigenus, Botryllus schlosseri, Botrylloides violaceus and Botrylloides leachi, were studied histologically. In every species, the egg follicle consisting of an egg and its inner and outer follicles, is attached to the follicle stalk, the vesicle being composed of a flat epithelium, which in its turn is connected to the atrial epithelium or to the brood pouch specialized from it. In B. schlosseri, the egg is ovulated into the atrial cavity and remains there held by the brood cup, of which the inner epithelium is derived from the follicle stalk and the outer one from the atrial epithelium. In B. primigenus, the brood pouch develops as a diverticulum of the atrial cavity, around the entrance of which a fold differentiates from the atrial epithelium and closes the pouch during embryogenesis. In both species of Botrylloides, the brood pouch is formed by the outgrowth of the thickened atrial epithelium into the blood space, the entrance of which is closed during embryogenesis. The discarded outer follicle completely disintegrates soon after ovulation in B. schlosseri, but part of it remains throughout embryogenesis in the blood space in B. primigenus or projecting into the interior of the brood pouch in Botrylloides. In primigenus, the testis, when it accompanies the egg follicle, is placed at the bottom of the brood pouch and the sperm is shed through the pouch prior to ovulation. In B. schlosseri and the Botrylloides species, the testis is located independently from the egg follicle and the sperm matures after ovulation.  相似文献   

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A new species of the genus Trematosphaeria was isolated and identified from the soil in Jiuzhaigou Nature Reserve, southwestern China. The new taxon was studied based on morphological characters and phylogenetic analyses of three nuclear loci, i.e., the internal transcribed spacer rDNA operon (ITS), and large and small subunit nuclear ribosomal DNA (nuc28S rDNA, nuc18S rDNA). The analyzed Trematosphaeria species were clustered in several clades within the Pleosporales and the genus was shown to be polyphyletic. The new species is introduced as Trematosphaeria terricola, and it is characterized by short-papillate ascomata with suborbicular ostiolum, 3-septate, cinnamon-brown, fusiform ascospores with narrowly rounded ends, verruculose at maturity. Trematosphaeria terricola is compared with morphologically similar species T. confusa, T. mangrovis, and T. pertusa, which differ from the former species in the number of septa, and the shape and size of the ascospores with or without a sheath. This is the first report of a Trematosphaeria isolate from alpine soil in China.  相似文献   

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符国瑷 《植物研究》2004,24(4):387-388
我国苏铁属(苏铁种)一新种, 即念珠苏铁。  相似文献   

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现分类系统中,双缘衣属隶属于子囊菌门,茶渍纲,厚顶盘亚纲,文字衣目,双缘衣科。全世界有48种,被确认为单系类群的小属。利用形态学、解剖学、生物化学以及分子生物学方法,对采自天山西部的双缘衣属地衣标本进行分类学研究,发现了双缘衣属地衣1个新种:绿盘双缘衣Diploschistes viridis (属于双缘衣亚属)。基于最大似然分析(ML)和贝叶斯分析(BI)构建了基于ITS位点系统发育树,详细描述该种的形态特征、分布及栖息地等情况,并提供了地衣体的彩色图片。  相似文献   

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Two new species of Xyridaceae, Xyris jolyi and X. coutensis, from Minas Gerais, Grazil, are distinguished from close relatives on the basis of morphological features including bracts, sepals, and leaves.  相似文献   

20.
郭英兰 《菌物学报》2013,32(Z1):133-135
报道生于蓼属Polygonum sp.植物上的假尾孢属1个新种:余氏假尾孢Pseudocercospora yui Y.L.Guo.文中提供了新种的拉丁文简介、形态描述、绘图及讨论.模式标本保存在中国科学院微生物研究所菌物标本馆(HMAS).  相似文献   

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