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81.
A new species of Psychodidae, Syntomoza matagalpensis from Nicaragua is described. Morphology of both male and female and notes on their biology are offered. 相似文献
82.
In this paper we report a new species of Dugesia of the family Dugesiidae from Madagascar, representing the fourth species of freshwater planarian known from this global biodiversity hotspot. In some respects the new species is aberrant, when compared with its congeners, being characterized by a head with smoothly rounded auricles, a peculiar course of the oviducts, including the presence of a common posterior extension, and by the asymmetrical openings of the vasa deferentia at about halfway along the seminal vesicle. Further, it is characterized by a ventral course of the ejaculatory duct with a terminal opening, very long spermiducal vesicles and unstalked cocoons. Its diploid chromosome complement with 18 chromosomes represents an uncommon feature among fissiparous species of Dugesia. 相似文献
83.
A checklist of onychiurid species from the Wanda Mountains in China is presented. Eighteen species belonging to twelve genera have been found, including two new species. Bionychiurus qinglongensis
sp. n. can be easily distinguished from other known species of the genus by the absence of pseudocelli on Th. I tergum and fewer number of vesicles in postantennal organ. Onychiurus heilongjiangensis
sp. n. is diagnosed by pseudocellar formulae as 32/133/33352 dorsally and 3/011/31120 ventrally, parapseudocellar formula as 0/000/111001+1m, ratio of anal spine/unguis as 0.6, unguiculus without inner basal lamella, and male ventral organ absent. 相似文献
84.
叉茎管蚜蝇属Tigridemyia与墨管蚜蝇属 Mesembrius和美管蚜蝇属 Mallota形态相似,过去曾被作为后二属的亚属.但此属的雄性外生殖器阳茎的射精管端部4分叉与墨管蚜蝇属和美管蚜蝇属区别明显,因此,其属地位应予肯定.作者在整理中国的食蚜蝇标本时,发现该属1新种,刺腿叉茎管蚜蝇Tigridemyia acanthogemurilis sp.nov,加之过去已记录的1种,我国已知叉茎管蚜蝇属2种.本文描述了新种,并给出了中国已知2种的检索表和形态特征图及其分布.模式标本保存于华南农业大学植保系昆虫标本室. 相似文献
85.
Merlinius paniculoides n. sp. is described from a bisexual Italian population found in northern Italy. This species has a coarsely annulated cuticle with approximately 30 longitudinal striae in addition to the six lateral field incisures; consequently the cuticle appears tessellate. The female tail is subcylindrical with a bluntly, rounded, non-annulated terminus. Merlinius paniculoides shares the tessellate cuticular ornamentation and the offset labial region with M. lenorus (Brown, 1956) Siddiqi, 1970 and M. tartuensis (Krall, 1959) Siddiqi, 1970. It differs from M. lenorus by the higher c and lower c'' ratios (c = 16-19 vs. 12-15 and c'' = 2.2-2,8 vs. 3.7) and greater number of longitudinal striae (28-32 vs. 24). It differs from M. tartuensis by a fewer number of annuti from stylet knob base to lip constriction (8-9 vs. 21), shorter stylet (19-21 vs. 24 μm), presence of males, and higher c'' value (c'' = 2.2-2.8 vs. 1.9). 相似文献
86.
Tim M. Berra 《Environmental Biology of Fishes》1997,50(1):1-12
Of the approximately 1.5 million species described to date, about 48 170 (3.2%) are vertebrates. Of these 24 618 (51%) are
fishes. Amazingly, 41% of fishes are found in fresh water which makes up a negligible percentage of the water on earth. The
sea accounts for 97% of all water on the planet and contains 58% of the fish species, mostly from shallow, warm-coastal areas.
The families Cichlidae, Cyprinidae, Characidae, Loricariidae, and Cyprinodontidae constitute about half of all the recently
described new freshwater fish species named in the period 1978–1993. The Gobiidae and Serranidae are the marine families with
the largest number of recently described new species. The most new freshwater teleost names came from South America (39%),
Africa (32%) and Asia (17%). New fish species continue to be described at the rate of roughly 130–160 each year. An estimated
13 775 new fish names have been proposed in this century, representing about 56% of all currently known fish species. Three
species are discussed in detail to represent remarkable examples of 20th century fish discoveries: the coelacanth Latimeria
chalumnae, the salamanderfish Lepidogalaxias salamandroides of Western Australia, and the megamouth shark Megachasma pelagios.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
87.
Graham Williamson 《Plant Systematics and Evolution》1980,134(1-2):53-77
11 new taxa (8 new species, 3 new varieties) ofOrchidaceae are described from South Central Africa, including data on their habitat and distribution and discussions of their systematic affinities. 相似文献
88.
K. H. Rechinger 《Plant Systematics and Evolution》1980,134(1-2):127-131
Five new species are described:Eremostachys codonocalyx from NE. Iran (related toE. subspicata),E. stenocalycina from NE. Afghanistan (related toE. alberti andE. hissarica),E. salangensis from NE. Afghanistan (close toE. bamianica),E. freitagii from E. Afghanistan (similar but not closely related toE. vulnerans), andE. andersii from E. Afghanistan (similar but not closely related toE. vulnerans), andE. andersii from NE. Afghanistan of isolated systematic position.
Florae Iranicae praecursores 5–9. 相似文献
89.
随着免疫功能缺陷人群的增多,侵袭性真菌感染(invasive fungal infections,IFIs)的发病率和死亡率逐年上升,严重威胁人类健康。目前临床常用抗侵袭性真菌感染药物有三唑类(氟康唑)、多烯类(两性霉素B)、棘白菌素类(卡泊芬净)等,然而这些药物并不能满足临床需要,侵袭性真菌感染的死亡率仍居高不下。因此,本文着重于目前处于临床研究阶段的抗真菌感染新药,根据作用靶点不同依次介绍:作用于细胞壁的新型葡聚糖合成酶抑制剂CD101和SCY-078、几丁质合成酶抑制剂尼可霉素Z、GPI锚定蛋白抑制剂APX001;作用于细胞膜的CYP51抑制剂VT-1161和VT-1129、破坏细胞膜通透性药物CAmB;影响细胞代谢的嘧啶合成抑制剂F901318,以及生物制剂包括细胞表面凝集素样序列3蛋白疫苗(NDV-3)和抗真菌感染抗体Mycograb。本文主要综述了上述新药的研究进展,包括作用机制、体内外活性、临床研究结果等,为相关药物的研发与未来的临床应用提供参考。 相似文献
90.