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1.
Abstract. The female atrial system of members of the Polycystididae has been studied at the light microscopical level and compared among the constituent taxa. Based on the criteria of position and conjunction, hypotheses of homology are put forward and compared with the assessments of homology found in earlier literature. Contradictory terminology is synonymized and adapted to fit new findings that recognize homology among structures in different taxa. Based on differences in position and structure, 2 types of female duct are recognized: female duct type I and female duct type II. The term “female bursa” is restricted to a sperm resorbing organ at the proximal end of the female duct type I and/or at the end of a common oviduct. Some species have bundles of glands at the place where the oviduct(s) enter the female duct type I, which are considered homologous among these species. Different types of seminal receptacles are recognized. The term “insemination duct” is restricted to the ducts which in some species, in addition to the oviducts, connect the ovaries with the female duct type I. A single muscular duct, the common oviduct, connects the joined oviducts with the female duct type I in species of Duplacrorhynchus and is considered homologous with the similar duct present in some other species. A uterus is always present, entering the common genital atrium through its frontal wall, or entering a female duct type II. This morphological review of the female atrial system reveals a mosaic distribution of characters if applied to previous phylogenies that are based primarily on the male reproductive system. 相似文献
2.
Yurij V. Mamkaev 《Hydrobiologia》1995,305(1-3):15-19
Compared with Hennig's phylogenetical systematics which has as its aim the retracing of genealogical relations between taxonomic groups, evolutionary morphological systematics is equally justified. Classifications of basic plans, morphological types, and morphofunctional systems of organisms serve as the foundation of evolutionary morphological systems. They are constructed on the basis of thorough understanding and further iteration of morphological transformation in phylogenetical branches based on the constructional pecularities of the morphofunctional systems. The evolutionary morphological approach in systematics is important especially for elaborating macrosystems dealing with vastly divergant groups where it is impossible to trace their real genealogy. The general principles of evolutionary morphological systematics are considered. A variant of the classification system of the Plathelminthes is suggested. 相似文献
3.
J.-P. L'Hardy 《Hydrobiologia》1986,132(1):233-238
Karyology and reproductive biology of a marine population of the species complex Gyratrix hermaphroditus, from Roscoff (Brittany, France), have been investigated. A diploid complement of six chromosomes was determined from spermatogonial mitotic figures. One chromosome pair is metacentric, the second is intermediate between meta- and submetacentric, and the third is subtelocentric.In this population, regular meiosis occurs in both female and male germ lines, and the animals reproduce only by means of amphimictic eggs. Certain specimens of the population showed the elimination of one of the three bivalents during the first meiotic division in spermatogenesis. It seems that such animals produce normal and aneuploid sperm simultaneously; the aneuploid sperm are not capable of fertilization.The Roscoff population differs in its karyotype (2n = 6) from freshwater populations, which are either diploid (2n = 4) or polyploid (3n = 6, 4n = 8). These results suggest that aneuploidy played a role in the differentiation of freshwater populations from an originally marine species complex. 相似文献
4.
小达氏涡虫属一新种(扁形动物门,单肠目,达氏科) 总被引:1,自引:1,他引:1
报道中国小达氏涡虫属1新种:湖南小达氏涡虫Microdalyellia humanensis nov.sp.,模式标本采集于湖南新宁县莨山镇黄背村(26°44′N,110°84′E),对新种涡虫的形态特征作了详细描述,所有标本保存在深圳大学生命科学学院. 相似文献
5.
Abstract. This study is focused on the formation and function of sagittocysts, which are secretions typical of members of the acoel family Sagittiferidae. The needle-shaped sagittocysts are produced in specialized gland cells (sagittocytes) whose distal necks are often surrounded by muscle mantles. Contraction of the muscle mantle ejects the sagittocyst. We establish a model for the development of sagittocytes and muscle mantles out of the stem cell pool of the new acoel species Symsagittifera corsicae . We used various techniques, especially interference and phase-contrast microscopy of living specimens as well as labeling of the body-wall musculature, for species characterization. In addition to the morphological features, we provide the third complete sequence of the 18S rDNA gene in the family Sagittiferidae. 相似文献
6.
中国涡虫一新纪录科达氏涡虫属一新种(单肠目,达氏科) 总被引:1,自引:7,他引:1
记述了中国涡虫纲单肠目1新纪录科达氏科达氏涡虫属1新种,即中国达氏涡虫Dalyellia sinensis sp.nov..新种的主要鉴别特征是:表皮下有许多单细胞绿藻Chlorella sp.,体表呈绿色;体长2 200 μm,体中部宽475μm,几丁质阴茎长178 μm,柄2根,柄长100μm,柄宽13~15 μm,两柄间距188 μm,分支2条,呈心形排列,阴茎上有几丁质刺22根,分支末端的刺长是基部刺长的1/5.标本保存在深圳大学生命科学学院形态学研究室. 相似文献
7.
A new species of deep‐living dragonet Callionymus omanensis from Oman is described on the basis of a single male specimen collected in a trawl from 500 m depth off the coast of Oman. The new species is characterized within the subgenus Bathycallionymus by having a small branchial opening; head short (3·9 in proportion to standard length); eye large (2·4 in proportion to head length); preopercular spine with a long, upcurved main tip, with a small antrorse barb and a larger antrorse spine, and with a strong antrorse spine laterally at the preopercular‐spine base, ventral margin smooth; first dorsal fin slightly higher than second dorsal fin (male); second dorsal fin distally straight; 17 pectoral fin rays; distal end of caudal fin slightly pointed, with two median unbranched rays bearing short filaments; first dorsal fin with basal black spot reaching from first to fourth membranes, third membrane with an ocellated distal black blotch; second dorsal fin with vertical dark grey bars; distal three‐fourths of anal fin black; upper half of caudal fin with oblique dark grey bars; pelvic fin dark grey, second ray basally with a black blotch. The new species is compared with similar species. Revised keys to callionymid species of the western Indian Ocean and the Red Sea, as well as species of the subgenus Bathycallionymus, are presented. 相似文献
8.
WIM R. WILLEMS TOM J. ARTOIS WOUTER A. VERMIN ERNEST R. SCHOCKAERT 《Zoological Journal of the Linnean Society》2004,141(2):271-296
A morphological and taxonomic account of the genus Trigonostomum is provided. All known species are discussed and briefly re-described where necessary. Seven new species are described: T. franki from Curaçao, Florida (USA), the East African Coast and New Caledonia, T. nataschae from the French sub-Antarctic island Kerguelen, T. spinigerum from New Caledonia and T. watsoni from the Australian East Coast and New Caledonia. T. tori and T. galapagoensis , both formerly enclosed in T. setigerum , are considered new species, while T. australis also belongs to the same species group. Proxenetes denhartogi is transferred to Trigonostomum . Based on a comparison of old and new material, T. marki is synonymized with T. penicillatum , while T. prytherchi and T. divae are regarded as junior synonyms of T. lilliei ; T. intermedium and T. quadrifolium are considered synonyms of T. coronatum . Three species are considered species inquirendae : T. brunchorsti , T. piriforme and Marinellia lingulifera . Similarities and differences of the 17 valid species are discussed and summarized in an identification key. © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society , 2004, 141 , 271–296. 相似文献
9.
All members of the Fecampiidae are endoparasites. Since 1964 when only four species were known, four new species and 11 cocoon types, made by as many unknown species, have been described.The Fecampiidae are distributed in all major oceans from shallow waters to more than 5000 m depth. 相似文献
10.
Two new turbellarian species, Gieysztoria shantouensis Zhang, Li Wang, sp. nov. and G. huizhouensis Zhang, Wu Wang, sp. nov. are described, which were collected from ditches in Shantou and Dongjiang River, Huizhou of Guangdong Province, respectively. G. macrovariata(Weise, 1942) was firstly recorded in China. All specimens examined were deposited in National Zoological Museum, Institute of Zoology, Chinese Academy of Sciences, China. 相似文献
11.
Ladurner P Pfister D Seifarth C Schärer L Mahlknecht M Salvenmoser W Gerth R Marx F Rieger R 《Histochemistry and cell biology》2005,123(1):89-104
Monoclonal antibodies (mABs) against various cell types of the basal free-living flatworm Macrostomum sp. were produced by immunising Balb/c mice with cell suspensions of disintegrated animals. We identified 360 positive supernatants with specific staining of various tissues, cell types, patterns or structures. Here we report immunocytochemical characterisation, histological stainings and isotyping of 11 mABs specific for muscle cells (MMu-1, MMu-2, MMu-3, MMu-4), digestive and prostate glands (MDr-1 and MDr-2, MPr-1), epidermal cells (MEp-1), the ventral nerve cord including neuron clusters (MNv-1), gastrodermal cells (MDa-1) and spermatids (MSp-1). Confocal microscopy, histological techniques, electron microscopy and immunoblotting were applied to demonstrate stainings in juveniles, adults, starved or well-fed animals. Considering the current lack of specific markers the obtained mABs will be particularly helpful studying embryonic and postembryonic development, pattern formation, cell differentiation, regeneration and reproductive allocation in Macrostomum sp., and possibly other basal flatworms. The small size, ease of culturing, short generation time, transparency and the basal phylogenetic position specify Macrostomum sp. as a suitable model organism for comparative analyses within Platyhelminthes and to Drosophila and C. elegans. 相似文献
12.
Matthew Hooge Andreas Wallberg Christiane Todt Aaron Maloy Ulf Jondelius Seth Tyler 《Hydrobiologia》2007,592(1):439-454
Species of the genus Hofstenia are voracious predators and among the largest and most colorful of the Acoela. They are known from Japan, the Red Sea, the
North Atlantic islands of Bermuda and the Bahamas, and the Caribbean and in a variety of habitats including the rocky intertidal,
among Thalassia sea grass, on filamentous algae and decaying mangrove leaves. Certain color morphs associated with each of these habitats
seem to have confused the taxonomy of the group. While brown-and-white banding and spotting patterns of Hofstenia miamia and Hofstenia giselae are distinctive for species associated with mangrove leaves and Thallasia sp. and are likely to be cryptic for these specific environments, we find some evidence to suggest that the coloration is mimicry
of a nudibranch with aposematic coloration. The common plan in these patterns is one with three variously solid or spotted
lighter cross bands on a dark background. Our examination of museum type material and live specimens of Hofstenia collected from Bahamas, Belize, Bermuda, and Panama revealed no internal morphological differences between the Hofstenia species occurring in the Caribbean. Similarly, our analyses of 18S and 28S molecular sequence data revealed no significant
differences among specimens. Accordingly, we declare that Hofstenia giselae is a junior synonym of Hofstenia miamia, the three-banded panther worm.
Electronic supplementary material The online version of this article (doi: ) contains supplementary material, which is available to authorized users.
Handling editor: K. Martons 相似文献
13.
旋涡虫属一新种(单肠目,隐头吻亚目,多囊科) 总被引:4,自引:0,他引:4
报道采自中国广东湛江的淡水旋涡虫属1新种:中国旋涡虫Gyratrix sinensis sp.nov.对新种涡虫的形态特征作了详细描述,并与旋涡虫属近似种进行了比较. 相似文献
14.
中国涡虫一新纪录科(扁形动物门,单肠目,盲扁虫科)背睾涡虫属一新种 总被引:1,自引:0,他引:1
记述了中国涡虫单肠目1新纪录科背睾涡虫属1新种,即中国背睾涡虫Phaenocor asinensis sp.nov.。新种的主要鉴别特征是:外轮廓呈长子弹形,后缘呈刀切状;精巢长度占体长的2/3,位于卵黄腺的背部。阴茎表面小刺呈犬牙状,其内折部中段具4个矩形的粗刺。子宫有2个开口,一端连接卵巢,另一端连接生殖腔。卵黄腺呈条形,具短分支,左右卵黄腺无衔接。生活于淡水。标本保存在深圳大学生命科学学院形态学研究室。 相似文献
15.
达氏科中国一新纪录属及三新种(扁形动物门,单肠目,达氏亚目) 总被引:7,自引:1,他引:7
报道淡水扁形动物中国1新纪录属--小达氏涡虫属及3新种:木鱼小达氏涡虫Microdalyellia muyuensissp.nov.,神农架小达氏涡虫M.shennongjiae sp nov.,中国小达氏涡虫M sinensis sp.nov..前2种标本采于湖北省神农架木鱼镇的溪流,后1种采于广东汕头市郊区小河;对3新种涡虫的形态特征作了详细描述和比较,并与近似种进行了比较. 相似文献
16.
达氏科中国一新纪录属一新种(扁形动物门,单肠目,达氏亚目) 总被引:5,自引:4,他引:5
报道了单肠目达氏亚目达氏科涡虫中国1新纪录属,杰氏涡虫属及1新种:深圳杰氏涡虫Gieysztoria shenzhensis sp.nov..对其形态特征作了详细描述,并与近似种进行了比较. 相似文献
17.
容粗徨;刘旭坤;赵佳琪;汪安泰 《四川动物》2016,35(1):97-103
: 本文记述淡水涡虫类单肠目Rhabdocoela达氏科Dalyelliidae小达氏涡虫属Microdalyellia一新种,广东小达氏涡虫Microdelyellia guangdongensis Wang et Rong, sp. nov.,模式标本由卢彦宏于2013年6月9日采自广东省深圳市石岩水库(22°40'58\"N,113°53'42\"E);杰氏涡虫属Gieysztoria一新种,七星岩杰氏涡虫Gieysztoria qixingyanensis Wang et Rong, sp. nov.,模式标本由刘旭坤于2014年8月6日采自广东省肇庆市七星岩风景区(23°04'32\"N,112°28'46\"E)。对2个涡虫新种的形态特征作了详细描述,并分别与小达氏涡虫属和杰氏涡虫属近似物种进行了比较。所有标本保存于中国科学院国家动物博物馆。 相似文献
18.
19.
R. Sluys M. Kawakatsu 《Journal of Zoological Systematics and Evolutionary Research》2006,44(4):274-284
We explore and review the taxonomic distribution of morphological features that may be used as supporting apomorphies for the monophyletic status of various taxa in future, more comprehensive phylogenetic analyses of the dendrocoelid freshwater planarians and their close relatives. Characters examined are: (i) musculature of the pharynx; (ii) anatomy of the eye; (iii) distribution of testis follicles along the longitudinal axis of the body; (iv) epidermis of the body wall; (v) musculature of the ventral body wall; (vi) presence or absence of a penis papilla; (vii) position of the mouth opening; and (viii) anterior adhesive organ. A phylogenetic hypothesis, in the form of a character state tree, is developed. This hypothesis suggests that the Kenkiidae should be resurrected as a separate family, sharing a sistergroup relationship with the Dendrocoelidae. This sistergroup relationship is supported by the shared presence of an apomorphic anterior adhesive organ. Although the shape of the anterior adhesive organ, both within and between kenkiids and dendrocoelids, may differ considerably between species, they are all constructed according to the same principles. The monophyly of the Kenkiidae is supported by the presence of an apomorphic thickening of the marginal zone of the epidermis and presumably also by the presence of prepharyngeal testes. Within the Kenkiidae, the genus Macrocotyla should be considered as a junior synonym of Kenkia, which is characterized by the presence of an apomorphic ‘planariid pharynx‐type 2’. The monophyly of the Dendrocoelidae is suggested by the presence of a dendrocoelid type of pharynx. It is shown that multicellular eye cups with numerous photoreceptor cells are not restricted to the Dugesiidae and the Terricola but are also characteristic for the Dendrocoelidae; the phylogenetic implications of this character state distribution are discussed. It is pointed out that in planarians there may be a relationship between: (i) body size, the size of an eye cup and the number of its constituent pigment cells; and (ii) the size of an eye cup and the number of photoreceptor cells that it contains. Some tentative phylogenetic groups are suggested on the basis of the following presumed apomorphic characters: presence of transverse fibres in the ventral subepidermal musculature, presence of an extra longitudinal muscle layer in the outer pharynx musculature, a mouth opening that has shifted anteriad. It is suggested that the presumed monophyly of the genus Bdellocephala is supported by the apomorphic absence of a penis papilla, combined with a penial lumen provided with many plicae. 相似文献
20.
Photoreceptor structure and function in the Platyhelminthes has traditionally been treated separately in the Turbellaria on one hand and the conventional parasitic classes on the other. In this paper, an attempt is made to bring together data from the literature and to highlight deficiencies and areas where a more integrated approach would be beneficial. This is done with particular reference to the endosymbiont genus Paravortex which belongs to the Turbellaria but which functionally has more similarities to the parasitic platyhelminths especially with regard to the host-finding requirement of the larval stages. 相似文献