首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 0 毫秒
1.
Two new species of Dalyellidae, Dalyellia callvucurai n. sp. and Gieysztoria namuncurai n. sp., are described from temporary freshwater environments in central Buenos Aires Province, Argentina. The ultrastructure of the stylets of both species is also described. The new species of the genus Dalyellia is the second species of the genus found in the neotropics and the first whose stylet has been studied with scanning electron microscopy. Gieysztoria namuncurai n. sp. joins the seven species of the genus known in Argentina. The ultrastructural characteristics of the stylet place it in the Inaequales group, with complex stylets.  相似文献   

2.
3.
报道了大口虫目大口虫科中国一新纪录种,即帆大口涡虫Macrostomum saifunicum Nasonov,1929,详细研究了该涡虫的个体发育与角质阴茎发育的关系.结果 表明:1) 帆大口涡虫角质阴茎端部结构在个体发育的第9 d 一次性成型,终身不变,是一个稳定的关键分类性状; 2) 个体发育至第20 d 后,角质阴茎长度达140 μm,第40 d后个体进入衰老期,其角质阴茎长度超过160 μm,指出角质阴茎的长度不是一个稳定的分类性状; 3) 根据作者多年的野外采集,发现北京、安徽、湖南、江西、广东均有帆大口涡虫分布,指出该物种是中国常见的分布较广的物种,并提示大口涡虫是一种在教学和科学研究方面理想的实验动物.  相似文献   

4.
5.
Berdnik  S. V.  Tokinova  R. P. 《Biology Bulletin》2021,48(8):1157-1159
Biology Bulletin - Macrostomum longituba (Platyhelminthes, Rhabditophora, Macrostomorpha), formerly known as a representative of the Mediterranean brackish water complex, is recorded for the first...  相似文献   

6.
7.
Scheller U 《ZooKeys》2011,(115):19-26
Two new species of Pauropoda are described from USA, Kionopauropus alyeskaensissp. n. (Pauropodidae), and Eurypauropus arcuatussp. n. (Eurypauropodidae). The genus Kionopauropus is reported from the Western Hemisphere for the first time.  相似文献   

8.
Neoblasts in Platyhelminthes are the only cells to proliferate and differentiate into all cell types. In Macrostomum lignano, the incorporation of 5'-bromo-2'-deoxyuridine (BrdU) in neoblasts confirmed the distribution of S-phase cells in two lateral bands. BrdU labeling for light and for transmission electron microscopy (TEM) identified three populations of proliferating cells: somatic neoblasts located between the epidermis and gastrodermis (mesodermal neoblasts), neoblasts located within the gastrodermis (gastrodermal neoblasts), and gonadal S-phase cells. In adults, three stages of mesodermal neoblasts (2, 2-3, and 3) defined by their ultrastructure were found. Stage 1 neoblasts where only seen in hatchlings. These stages either were phases within the S-phase of one neoblast pool or were subsequent stages of differentiating neoblasts, each with its own cell cycle. Regular TEM and immunogold labeling provided the basis for calculating the total number of neoblasts and the ratio of labeled to non-labeled neoblasts. Somatic neoblasts represented 6.5% of the total number of cells. Of these, 27% were labeled in S-phase. Of this fraction, 33% were in stage 2, 46% in stage 2-3, and 21% in stage 3. Immunogold labeling substantiated results concerning the differentiation of neoblasts into somatic cells. Non-labeled stage 2 neoblasts were present, even after a 2-week BrdU exposure. Double labeling of mitoses and FMRF-amide revealed a close spatial relationship of mesodermal neoblasts with the nervous system. Immunogold-labeled sections showed that nearly 70% of S-phase cells were in direct contact or within 5 microm from nerve cords.  相似文献   

9.
10.
The species of the genus Chrysotus Meigen from Shanxi, China are reviewed. Two species are described as new to science: C. shanxiensis sp. nov. and C. thornpenis sp. nov. C. biprojicienus Wei & Zhang and C. serratus Wang & Yang are recorded from Shanxi for the first time. A key to the species of Chrysotus from Shanxi is presented.  相似文献   

11.
Specimens of Potamotrygonocestus used in the present taxonomic and phylogenetic study were collected in freshwater potamotrygonids from the Rio Paraná (Puerto Reconquista, Santa Fé, Argentina; 59°42'W, 29°29'S) during February 1995, and from the Amazon region of Brazil during September to December 1996, supplemented by specimens previously deposited in museum collections. Six species of Potamotrygonocestus were recognized ( P . amazonensis , P . chaoi sp. n., P . fitzgeraldae sp. n., P . magdalenensis , P . maurae sp. n., P . travassosi ), for which an identification key is provided. Potamotrygonocestus orinocoensis is considered a junior synonym of P . travassosi . Additional specimens of Potamotrygonocestus may represent two undescribed species. A phylogenetic analysis of six morphological characters for the six named species of Potamotrygonocestus generated a single tree eight steps long, with a consistency index of 0.87, a retention index of 0.90, and a rescaled consistency index of 0.79 with the following topology: ( P . maurae sp. n. (( P . amazonensis  +  P . magdalenensis ) ( P . chaoi sp. n. ( P . fitzgeraldae sp. n. +  P . travassosi )))).  相似文献   

12.
13.
The ultrastructure of the epidermis of seven species of polyclad flatworms (Phaenocelis medvedica, Phaenocelis peleca, Pleioplana atomata, Boninia divae, Pericelis orbicularis, Enchiridium periommatum, and Cycloporus variegatus) representing six families is described. In all seven species, the epidermis consists of a single layer of columnar cells that rests on a bipartite basement membrane. Epithelial cell surfaces are covered by numerous microvilli and cilia. Cilia contain microtubules arranged in the 9 + 2 pattern, and from their basal bodies two striated rootlets arise, a rostrally directed one running parallel to the apical cell membrane, and a vertical one at a right angle to the first rootlet. Numerous epithelosomes and mitochondria occupy the apical parts of the cells. The basal part of the cells is highly folded, forming a cell web that connects to the basement membrane. The basement membrane consists of a thin basal lamina and a thick, multilayered reticular lamina. The number of layers in the reticular lamina varies among the different species and appears to be correlated with body size. Numerous canals containing either pigment granules or nervous processes perforate the basement membrane. We have identified four different types of glands: rhabdite glands, rhabdoid glands, mucoid glands containing vacuoles filled with flocculent material, and mucoid glands resembling thread cells of hagfish slime glands. The latter have been found only in P. orbicularis. Pigment cells were found in all species examined with the exception of C. variegatus, which takes its coloration from its ascidian prey. Our results further support the unique taxonomic status of Boniniidae.  相似文献   

14.
Xin Sun  Donghui Wu 《ZooKeys》2014,(425):99-111
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 qinglongensissp. 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 heilongjiangensissp. 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   

15.
We describe two new species and redescribe one in the polychaete genus Amphicorina Claparède, 1864 (Sabellidae) from Hokkaido, Japan. Amphicorina ascidicolasp. n. differs from its 38 congeners chiefly in the reduction of the collar, but also in having three pairs of radioles, one pair of ventral radiolar appendages, a bifurcate ventral lobe on the anterior peristomial ring, six abdominal chaetigers, and a large anterior tooth on the abdominal uncini. Amphicorina ezoensissp. n. has a crenulated collar, three pairs of radioles, and more than eight (12) abdominal chaetigers; Amphicorina ezoensis shares these character states with Amphicorina anneae (Rouse, 1994), Amphicorina eimeri (Langerhans, 1880), and Amphicorina persinosa (Ben-Eliahu, 1975), but differs from them in having two pairs of ventral radiolar appendages and a non-oblique collar. Amphicorina mobilis (Rouse, 1990) was previously known only from the type locality (New South Wales, Australia), but we identify our Japanese material as conspecific on the basis of morphological and molecular similarity.  相似文献   

16.
Systematic Parasitology - Recent occasional examinations of two species of eels (Anguilliformes: Anguillidae) in Japan, the Japanese eel Anguilla japonica Temminck & Schlegel from central...  相似文献   

17.
18.
A method for studying whole mount flatworm embryos based on freeze-cracking of the eggs is described. This method allows successful immunohistological and immunocytological studies of whole mount embryos. It does not require the use of sharpened needles or a microinjection system to puncture the eggshell. Moreover, this method is more practical and less time-consuming than classical puncturing and much cheaper than the use of a microinjection system. The advantages of this method are illustrated by results of several immunolocalisation experiments in the macrostomid flatworm Macrostomum lignano. The optimal procedure and crucial steps for this method are discussed. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

19.
刘长明 《昆虫学报》2002,45(Z1):88-92
 首次报道了中国毛缘小蜂属Lasiochalcidia Masi种类,描述了该属细角毛 缘小蜂L. gracilantenna sp. Nov.和赤亮毛缘小蜂L. rufipolita sp. Nov.2个新 种,并记述1新记录种披绒毛缘小蜂L. pilosella。文中提供了毛缘小蜂属中国已知种 检索表。  相似文献   

20.
刘长明 《昆虫学报》2002,45(2):88-92
首次报道了中国毛缘小蜂属Lasiochalcidia Masi种类,描述了该属细角毛缘小蜂L. gracilantenna sp. Nov.和赤亮毛缘小蜂L. rufipolita sp. Nov.2个新种,并记述1新记录种披绒毛缘小蜂L. pilosella。文中提供了毛缘小蜂属中国已知种检索表。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号