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1.
The gross morphology of the gas bladder is described and compared for representatives of all valid genera of Pseudopimelodidae (Siluriformes). Cephalosilurus albomarginatus and species of Batrochoglanis, and Microglanis have the most basic form: a large, cordiform gas bladder with a simple internal T‐shaped septum. Cephalosilurus apurensis, C. fowleri, and C. nigricauda also have a large, cordiform gas bladder, but they have well‐developed trabeculae associated with the internal T‐shaped septum, and a pair of well‐developed constrictor muscles inserted on the external wall; the latter feature is present in most species of Pimelodidae, but absent in all other catfishes. The monotypic Lophiosilurus alexandri also has well‐developed constrictor muscles, and its gas bladder is moderately sized. The species of Pseudopimelodus and Cruciglanis have a diminutive gas bladder partially divided into two lateral sacs without internal communication, and lack constrictor muscles. The parapophysis of the fourth vertebra is a wide and long shelf connected to the dorsal surface of the gas bladder in most pseudopimelodid genera. However, in the species of Pseudopimelodus and Cruciglanis the parapophysis of the fourth vertebra is shorter and has its anterior ramus folded back, partially covering the gas bladder anteroventrally; and the tympanic opening is smaller than in species of the other genera. Five phylogenetic characters are proposed based on the morphology of the gas bladder and associated structures in species of Pseudopimelodidae, and the evolution of those characters in the family is discussed. J. Morphol., 2011. © 2011 Wiley‐Liss, Inc.  相似文献   

2.
In 1987, 4516 species and 339 genera of the phylum Apicomplexa had been named. They consisted of the gregarines (subclass Gregarinasida) (1624 named species and 231 named genera), the hemogregarines (family Haemogregarinidae) (399 species and 4 genera), the eimeriorins (order Eimeriorida) (1771 species and 43 genera), the hemospororids (order Haemospororida) (444 species and 9 genera), the piroplasmids (order Piroplasmorida) (173 species and 20 genera), and a few others (105 species and 32 genera). The first apicomplexan protozoon was seen by Antony van Leeuwenhoek; in 1674 he saw oocysts of Eimeria stiedai in the gall bladder of a rabbit. The first member of the phylum to be named (by Dufour in 1828) was Gregarina ovata in earwigs. During the quarter century 1826–1850, 41 species and 6 genera of Apicomplexa were named. These numbers increased progressively. In the quarter century 1951–1975, 1873 new species and 83 new genera were named. Data are given for the numbers of named species and genera of apicomplexan protozoa of each group known in 1850, 1875, 1900, 1925, 1950, 1975, and 1987.  相似文献   

3.
Progress in taxonomy of the Apicomplexan protozoa   总被引:6,自引:0,他引:6  
In 1987, 4516 species and 339 genera of the phylum Apicomplexa had been named. They consisted of the gregarines (subclass Gregarinasida) (1624 named species and 231 named genera), the hemogregarines (family Haemogregarinidae) (399 species and 4 genera), the eimeriorins (order Eimeriorida) (1771 species and 43 genera), the hemospororids (order Haemospororida) (444 species and 9 genera), the piroplasmids (order Piroplasmorida) (173 species and 20 genera), and a few others (105 species and 32 genera). The first apicomplexan protozoon was seen by Antony van Leeuwenhoek; in 1674 he saw oocysts of Eimeria stiedai in the gall bladder of a rabbit. The first member of the phylum to be named (by Dufour in 1828) was Gregarina ovata in earwigs. During the quarter century 1826-1850, 41 species and 6 genera of Apicomplexa were named. These numbers increased progressively. In the quarter century 1951-1975, 1873 new species and 83 new genera were named. Data are given for the numbers of named species and genera of apicomplexan protozoa of each group known in 1850, 1875, 1900, 1925, 1950, 1975, and 1987.  相似文献   

4.
Aseeva NL 《Parazitologiia》2003,37(2):159-162
Three new species of mixosporidia of the genera, Myxidium and Myxoproteus, from the gall bladder and urinary bladder of fishes from Japan Sea: Myxidium licodae sp. n., M. rarum sp. n., and Myxoproteus ovale sp. n.  相似文献   

5.
The distribution of the swim bladder was examined in 20 species representing all four genera (Percina, Etheostoma, Crystallaria, and Ammocrypta) of darters (Etheostomatini). Including data on species examined in other studies, swim bladders have been found in 15 of 17 species of Percina, but were absent in Crystallaria asprella, Ammocrypta pellucida, and the 18 species of Etheostoma examined. Relative swim bladder length in Percina was shown to be positively correlated with body size. Although not statistically significant, swim bladder size also correlates with habitat (riffle, run, or pool) and swimming behavior (midwater or benthic).  相似文献   

6.
The anatomy of the gas bladder of Diodontidae (porcupinefishes) and Tetraodontidae (pufferfishes) was studied on the basis of dissections and magnetic resonance imaging. Among the examined taxa of Tetraodontiformes, only puffers and porcupinefishes possess a thick walled and dorsally U‐shaped or crescent‐moon‐shaped gas bladder. In the tetraodontid genus Lagocephalus the gas bladder is reduced to a rudiment. The species belonging to the genera Canthigaster, Arothron, and some species of Tetraodon differ in the positioning of their crescent‐moon‐shaped gas bladder. These observations confirm the close relationship of: (i) Diodontidae and Tetraodontidae and (ii) Canthigaster, Arothron, and some species of Tetraodon. The heterogeneity of the genus Tetraodon is supported by the gas bladder morphology, as previously suggested by molecular studies. J. Morphol. 275:894–901, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   

7.
The gross morphology of the gas bladder is described and illustrated for representatives of most species and all valid genera of the Auchenipteridae (Siluriformes). Although, a simple cordiform gas bladder is present in some species of the family, others are characterized by their distinctive gas‐bladder shape and diverticula disposition. An acute posterior end of the gas bladder characterizes Centromochlus heckelii and C. macracanthus, and is variably present in specimens of Auchenipterus. Tocantinsia piresi and Asterophysus batrachus have distinctive gas bladders differing in number of diverticula (two or many). The two species of Trachycorystes are diagnosed based on their gas bladder morphology: T. menezesi has a simple cordiform bladder, whereas T. trachycorystes has a pair of lateral diverticulum and, usually, a well‐developed terminal diverticulum. Species of Auchenipterichthys are characterized by having a secondary bladder with simple chamber. Short or elongate and divergent terminal diverticula are exclusive to most cis‐andine species of Trachelyopterus. Tetranematichthys and trans‐andine species of Trachelyopterus share a well‐developed secondary chamber or terminal diverticula ventrally or dorsally connected to the posterior chambers. The small‐sized species of Ageneiosus have well‐developed gas bladders with a pair of posterior diverticula, whereas large‐sized species have a reduced gas bladder with tunica externa varying from non‐, partially, or completely ossified. Eight phylogenetic characters are proposed based on the morphology of the gas bladder and associated structures in species of Auchenipteridae, and the evolution of those characters in the family discussed. J. Morphol., 2012. © 2012 Wiley Periodicals, Inc.  相似文献   

8.
The interaction of bacteria belonging to several genera with the bladder epithelium was studied. An in vivo rat bladder model system was used to evaluate the cytopathic effects of members of eight representative genera of bacteria and six strains ofEscherichia coli on the bladder surface. Alterations were noted mainly with the Gram-negative bacteria (Escherichia, Klebsiella, Enterobacter, Proteus, Pseudomonas), although some strains were associated with more cytopathology than others. Foci of cytopathology consisted of swelling, exfoliated epithelial cells, strand formation, and ulceration. Aggregates of bacteria, epithelial cells, and debris were shed into the bladder lumen. In contrast, members of three genera of Gram-positive organisms (Lactobacillus, Streptococcus, Staphylococcus) caused little or no cytopathology. The study strongly suggests that the bladder responds in a relatively uniform manner to viable Gram-negative organisms, while the response to Gram-positive organisms is minimal.  相似文献   

9.
The forces involved in the buoyancy of the genus Synodontis are unusually large owing to the well-developed cephalo-nuchal shield possessed by all members of the genus, and the large swim bladder and high levels of body fat needed to counteract this. A new method of determining the quantity of crude lipid in the tissues was developed and tested against a recognized method. Negative correlations were found between the total quantities of fat present and the volumes of the swim bladder for several species. Two species which maintained neutral buoyancy but occupied different ecological niches were found to achieve neutrality by different means, one possessing an abnormally large swim bladder and the other very large quantities of fat. The amount of bone present was found to be considerably greater than in species from other genera.
Several species of this genus regularly invert and swim on their backs. Three of the species known to do this were found amongst the 16 species present in the man-made Lake Kainji on the River Niger in Nigeria. The orientations of many of the species were studied both under natural conditions and in the laboratory. Several possible causes of inversion were investigated, including both physical and behavioural factors. The position of the food source was found to be the most important factor controlling the orientation of the species. By manipulating this it was possible to persuade normally orientating species to invert, and inverting species to return to normal orientation. Three theories to explain the inverting habit are advanced and their merits discussed.  相似文献   

10.
The laterophysic connection (LC) is an association between bilaterally paired, anterior swim bladder extensions (horns) and medial openings in the supracleithral lateral line canals that diagnoses butterflyfishes in the genus Chaetodon. It has been hypothesized that the LC makes the lateral line system sensitive to sound pressure stimuli that are transmitted by the swim bladder horns and converted to fluid flow into the lateral line system via a laterophysic tympanum. The purpose of this study was to define variation in the morphology of the LC, swim bladder and swim bladder horns among 41 Chaetodon species from all 11 Chaetodon subgenera and a species from each of four non-Chaetodon genera using gross dissection, histological analysis as well as 2D or 3D CT (computed tomographic) imaging of live, anesthetized fishes. Our results demonstrate that the lateral line system appears rather unspecialized with well-ossified narrow canals in all species examined. Two LC types (direct and indirect), defined by whether or not the paired anterior swim bladder horns are in direct contact with a medial opening in the supracleithral lateral line canal, are found among species examined. Two variants on a direct LC and four variants of an indirect LC are defined by combinations of soft tissue anatomy (horn length [long/short] and width [wide/narrow], number of swim bladder chambers [one/two], and presence/absence of mucoid connective tissue in the medial opening in the supracleithrum). The combination of features defining each LC variant is predicted to have functional consequences for the bioacoustics of the system. These findings are consistent with the recent discovery that Chaetodon produce sounds during social interactions. The data presented here provide the comparative morphological context for the functional analysis of this novel swim bladder-lateral line connection.  相似文献   

11.
E. F. LoPresti 《Oecologia》2014,174(3):921-930
Trichomes on leaves and stems of certain chenopods (Chenopodiaceae) are modified with a greatly enlarged apical cell (a salt bladder), containing a huge central vacuole. These structures may aid in the extreme salt tolerance of many species by concentrating salts in the vacuole. Bladders eventually burst, covering the leaf in residue of bladder membranes and solid precipitates. The presence of this system in non-halophytic species suggests additional functions. I tested the novel hypothesis that these bladders have a defensive function against insect herbivores using choice, no choice, and field tests. Generalist insect herbivores preferred to feed on leaves without salt bladders in choice tests. In no choice tests, herbivores consumed less leaf matter with bladders. In a field test, leaves from which I had removed bladders suffered greater herbivory than adjacent leaves with bladders. Solutions containing bladders added to otherwise preferred leaves deterred herbivores, suggesting a water-soluble chemical component to the defense. This bladder system has a defensive function in at least four genera of chenopods. Salt bladders may be a structural defense, like spines or domatia, but also have a chemical defense component.  相似文献   

12.
Polystoma fuscus n. sp. (Polystomatidae, Polystomatinae) is described from the urinary bladder of Pelobates fuscus (Pelobatidae) in Bulgaria. Its general morphology is similar to that of other members of the genus but distinguished from them by the underdeveloped hamuli similar to the larval hamular primordia. The new species is also differentiated from the members of the genera of the subfamily Polystomatinae described without hamuli.  相似文献   

13.
New taxa are proposed for Nanopolystoma lynchi n. g., n. sp. from the urinary bladder and phallodeum of the caecilian Caecilia cf. pachynema and N. brayi. n. sp. from the urinary bladder of C. gracilis, both from South America. These are the first species of polystomatids to be described from caecilian hosts. The parasites are small with a maximum body length of 2 mm. The two gut caeca are not confluent posteriorly and have neither diverticula nor anastomoses. The haptor bears six well-developed suckers and one pair of hamuli. The single follicular testis lies in the mid-body and the ovary is small. Vaginae are present. A single large, operculate egg lies in the short uterus, which leads to an armed genital bulb. Neither the nature of the oncomiracidium nor the phylogenetic position of these worms is known. Nanopolystoma n. g. shares various morphological features with other polystomatid genera; however, the non-confluent gut-caeca lacking diverticula and the presence of skeletal elements in the haptoral suckers place it with the chelonian polystomes of the subfamily Polystomoidinae. These findings suggest that the caecilian host species are probably semi-aquatic. More polystomatid species are expected to be found in association with other species of Caecilia.  相似文献   

14.
Polystoma sodwanensis n. sp. andMetapolystoma porosissimae n. sp. are described as new species of the Polystomatidae parasitic in the urinary bladder of adultPtychadena porosissima collected in northern Natal, South Africa. Of 26 frogs examined, 11 host individuals were infected with one of the two parasite species, while in five both parasite species occurred. This is the first record of two different genera of polystomatids occurring together in one host species and the first record ofMetapolystoma in South Africa. The exceptional nature of the reported double infection is discussed in terms of host specificity within the Polystomatidae. Relevant information is given on the ecology and distribution of the host,Ptychadena porosissima.To whom correspondence should be addressed.  相似文献   

15.
1995~2003年调查并整理分析青海湟水流域的蝶类,有9科52属80种,其中凤蝶科1属2种,绢蝶科1属6种,粉蝶科8属22种,斑蝶科1属1种,眼蝶科12属13种,蛱蝶科15属18种,蚬蝶科1属3种,灰蝶科9属10种,弄蝶科4属5种.以古北界为主,青藏区最为丰富.  相似文献   

16.
秦岭太白山北坡蝶类组成共有78种,隶属6个科,43属。其中凤蝶科Papilionidae 3属8种,粉蝶科Pieridne 7属19种,眼蝶科sartyridae 5属9种,蛱蝶科Nymphalidae 15属27种,友蝶科Lycaenidae 7属8种,弄蝶科Hesperiidae 6属7种。新记录3种。  相似文献   

17.
陕西延安北洛河流域蝶类资源调查及区系研究   总被引:3,自引:0,他引:3  
通过对延安北洛河流域的蝶类资源进行调查,发现该地区共有蝴蝶6科54属75种(凤蝶科2属3种、粉蝶科7属10种、眼蝶科10属13种、蛱蝶科15属25种、灰蝶科11属15种、弄蝶科8属9种),其中34种为单属种,陕西省新纪录5种;区系结构分析表明该地区蝴蝶以古北种为主。标本保存于延安大学生命科学学院标本馆。  相似文献   

18.
庐山蕨类植物区系研究   总被引:2,自引:1,他引:1  
庐山共有蕨类植物39科87属247种(含变种、变型),其区系带有热带和温带双重性。其中鳞毛蕨科、水龙骨科、蹄盖蕨科、金星蕨科和铁角蕨科属种优势明显,共有38属160种,分别占总属数的43.7%和种数的64.8%,代表了该地区蕨类植物区系的一个重要特征。该区区系地理成分复杂,相互交错,其中热带性属占总属数的64.2%,温带性属占总属数的35.8%。东亚成分在该区系占有绝对优势,共有14属,占总属数的20.9%,中国特有属缺乏,特有种丰富,表明成分具有多样性并具有热带亲缘性,是亚热带向北温带的过渡地区。该区与井冈山、武夷山关系密切,与鼎湖山、秦岭和横断山关系疏远。  相似文献   

19.
白学礼 《蛛形学报》2013,(2):96-109
本文报道宁夏中气门螨22科61属238种。其中厉螨科15属63种,寄螨科9属38种,血革螨科2属24种,赫刺螨科1属21种,裂胸螨科6属18种,巨螯螨科2属14种,6科共记录35属178种,占其种类的74.79%,是宁夏中气门螨的主要构成者。  相似文献   

20.
陕西延安市区蝶类多样性初探   总被引:5,自引:1,他引:4  
延安市区有蝶类6科25属36种,其中凤蝶科2属3种;粉蝶科5属8种;眼蝶科3属5种;蛱蝶科7属10种;灰蝶科7属9种;弄蝶科1属1种。陕西省新记录5种。区系分析表明,该地区以广布种为优势种。  相似文献   

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