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温度和热驯化对胡氏大生熊虫运动行为的影响   总被引:1,自引:0,他引:1  
李晓晨  王立志 《动物学报》2005,51(3):516-520
对外温脊椎动物体温和运动能力关系的研究表明,外温动物的运动行为对身体温度的变化高度敏感(Bennett,1990)。在许多动物种类中,体温的升高或降低显著影响动物的运动能力(Huey,1982;Miller,1982;Watkins,2000),而运动能力的下降则影响外温动物逃避捕食者(Christian andTracy,19  相似文献   

3.
During the “Workshop on Arctic tardigrades” at the Danish Arctic Station (Qeqertarsuaq, Disko Island, Greenland) an undescribed species of Dactylobiotus was found in freshwater sediments of the Isunngua spring. We have the honour and pleasure to describe this new taxon that we dedicate to all participants of that symposium, naming the species Dactylobiotus octavi sp. n. The animals appear similar to Dactylobiotus dispar and Dactylobiotus haplonyx with the presence of a very short secondary branch in the claws of the first three pairs of legs, but they differ from these species in the size of claw and buccal tube width. This new species also has peculiar ornamented eggs. The eggshell consists of bowl-like processes, each one surrounded by a band of fine pores. A morphological parsimony analysis to identify phylogenetic relationships among D. octavi sp. n. and the other Dactylobiotus species was performed, obtaining inconclusive results. The discovery of this new species increases an unsolved paradox in tardigrade systematics related to the presence of closely related species which share a very similar morphology of the animals but clearly differ in their egg morphology, while, conversely, there are species belonging to different evolutionary lines that have similar eggs, but very different adult morphology. The finding of D. octavi sp. n. increases the already high number of species found in Disko Island and once again underlines the importance of tardigrades in the biodiversity of the Arctic area.  相似文献   

4.
The tribe Maxfischeriini, previously placed in Helconinae, is emended to subfamily status based on morphological and biological evidence. Proposed autapomorphies for Maxfischeriinae include: the presence of a pronotal shelf, forewing vein 1a and 2a present, although 1a nebulous, ventral valve of the ovipositor with serrations from tip to base and specialized egg morphology. The novel, pedunculate egg morphology is described for Maxfischeria, representing a new life‐history strategy among Braconidae. Based on egg and ovipositor morphology, we suggest that Maxfischeria is a proovigenic, koinobiont ectoparasitoid. Five new species of Maxfischeria Papp are described with an illustrated key to all species (Maxfischeria ameliae sp.n. , Maxfischeria anic sp.n. , Maxfischeria briggsi sp.n. , Maxfischeria folkertsorum sp.n. and Maxfischeria ovumancora sp.n. ). In addition to the identification key presented here, all known species of Maxfischeria can be separated using the barcoding region of cytochrome c oxidase subunit I (COI). Based on molecular data, the phylogenetic relationships among the six known species of Maxfischeria are as follows: (M. folkertsorum sp.n. (M. ovumancora sp.n. (M. briggsi sp.n. (M. anic sp.n. (M. tricolor + M. ameliae sp.n. ))))).  相似文献   

5.
In sixteen moss, lichen and mixed (moss/lichen) samples, collected from Estonia, Latvia and Lithuania, 291 specimens, 48 simplexes, including one exuvium with 6 eggs, and 8 free-laid eggs of eutardigrades were found. In total, 17 species, together with one new to science, were identified (all are new records for the Baltic states): Astatumen bartosi, Diphascon (Adropion) prorsirostre, D. (Diphascon) bullatum, D. (D.) pingue pingue, D. (D.) recamieri, D. (D.) rugosum, Hypsibius convergens, H. dujardini, H. cf. scabropygus, Isohypsibius ronsisvallei, I. sattleri, Macrobiotus harmsworthi harmsworthi, M. hufelandi hufelandi, Milnesium asiaticum, Milnesium tardigradum tardigradum, Minibiotus formosus sp. n. and Paramacrobiotus richtersi. The new species is most similar to Minibiotus gumersindoi, but differs from it mainly by the presence of two types of cuticular pores, the absence of a triangular or pentagonal arrangement of pores above a single large pore on legs, the presence of granulation on all legs and a different macroplacoid length sequence. In this paper we also provide photographs and morphometrics of H. cf. scabropygus.  相似文献   

6.
The immature stages of Holometabolan insects can provide valuable data both for taxonomy and phylogeny, but they are well known only for a negligible proportion of the described species. Scanning electron microscopy (SEM) analysis of all preimaginal stages of the lauxaniid species Meiosimyza decempunctata (Fallén 1820), M. platycephala (Loew 1847), M. rorida (Fallén 1820), M.?subfasciata (Zetterstedt 1838), Tricholauxania praeusta (Fallén 1820) and Aulogastromyia anisodactyla (Loew 1845) is presented for the first time. Detailed images of eggs and all three larval instars are provided along with illustrations of the cephaloskeleton and photos of puparia. The egg is rather simple, white, with developed longitudinal ridges. The body integument of all larval instars is smooth and uniform across species. The cephaloskeleton is slender; the mouth hooks are parallel, subhypostomal sclerites are arched and fusing to a ventral bridge. The puparium is brownish, oval, without calcareous deposits. Generally, the morphology of larvae and puparia is very conservative. On the other hand, the eggs show considerable degree of interspecific variability.  相似文献   

7.
Previous reports showed that the tepezcuintle (Agouti paca) is commonly infested by gastrointestinal parasites (GIP), mainly Eucoccidiida and helminths. However, there is no available information on the frequency of those parasites and their faecal egg excretions at different moments during the year. These information would provide a valuable baseline for the establishment of control strategies against GIP in tepezcuintles under captivity. The objectives of the present study were to determine the prevalence of GIP orders and genera that infest tepezcuintles under captivity and, to describe the dynamics of faecal egg and oocyst excretion in a year. Ten tepezcuintles were sampled (faeces) twice every month for twelve months. The faecal samples were processed by the flotation and McMaster techniques. Two orders of parasites were determined: Strongylida and Eucoccidiida. Two genera of nematodes were also determined: Strongyloides and Trichuris. The prevalence of Strongylida eggs, Eucoccidiida oocysts and Trichuris sp. eggs reached 10-20% of animals in certain months. The most important genus was Strongyloides, found in 60 to 100% of the animals year round. The average excretion of eggs in the group was 45 to 372 eggs per gram. Tepezcuintles kept under captivity in Yucatan are parasited with Strongyloides sp throughout the year, but only occasionally had oocysts of Eucoccidiida and eggs of Strongylida and Trichuris sp.  相似文献   

8.
Megasolena dongzhaiensis n. sp. was collected from the intestine of Scatophagus argus (Linnaeus) (Perciformes: Scatophagidae) from the Dongzhai Bay (110 degrees 32'-37'E, 19 degrees 51'-20 degrees 1'N), Hainan Province, China. It resembles Megasolena acanthuri Machida and Uchida, 1991 in having larger body size, but it differs from the latter species in having an oral sucker that is larger, instead of smaller, than the acetabulum (sucker length ratio 1:0.456-0.494, and width ratio 1:0.61-0.65 in M. dongzhaiensis n. sp., as opposed to 1:1.3-1.7 in M. acanthuri). Moreover, the cuticle is spinose rather than aspinose; there is a band of circular muscle in the pharynx, and its eggs are smaller instead of larger (0.062-0.068 x 0.036-0.039 in M. dongzhaiensis n. sp., compared with 0.087-0.103 x 0.058-0.072 in M. acanthuri). Finally, the intestinal bifurcation is anterior, instead of dorsal, to the acetabulum. It resembles other species of Megasolena Linton, 1910 in having oral sucker larger than the acetabulum, and in having a circular muscle band in the oral sucker and pharynx, but it differs in having a larger body and smaller eggs. This is the first record of a Megasolena species from ray-finned fishes as well as in China.  相似文献   

9.
Two hundred and forty-four specimens of Parapharyngodon riojensis n. sp. were found in the large intestines of 2 adult lizards Phymaturus punae collected from Quebrada del Leoncito, Province of La Rioja, Argentina. Parapharyngodon riojensis n. sp. represents the ninth species of the genus from the Neotropical Realm and the first species to be described from Argentina. It can be distinguished from all species of Parapharyngodon on the basis of the morphology of the anterior cloacal lip, the location of the ovary, and geographical distribution. Parapharyngodon riojensis n. sp. is most similar to P. senisfaciecaudus in that the ovary does coil around the esophagus and the number and location of caudal papillae in the males are the same. These 2 species differ in that the eggs of P. senisfaciecaudus are slightly asymmetrical, with a smooth, thin shell, whereas the eggs of P. riojensis are oval, with a punctate thick shell. In addition, the cloacal lip of males of P. senisfaciecaudus is smooth, whereas the cloacal lip of males of P. riojensis is echinate. A key to the species of Parapharyngodon in the Neotropical Realm is provided.  相似文献   

10.
Previous studies established the existence of morphologically highly similar amphiatlantic populations of the predominantly interstitial genus Microphthatmus (European coastline - from the German Bay to the Bay of Biscaya; American coastline - from Maine to Massachusetts and at the coast of North Carolina). Originally these three populations were seen as belonging to a single species. By using a broad spectrum of different methodologies for character investigations (especially through the use of electron microscopy) three, distinct species can now be distinguished: M. listensis Westheide 1967, M. nahantensis n. sp. and M. carolinensis n. sp. While habitat structure and external morphology - generally important in polychaete systematics - were found to be rather similar between the three species, this study uncovered distinct differences between the species in their internal organization. Such sharp differences could even be followed down to the ultrastructure of single cells (e. g. copulatory stylets, position and number of ovaries, sperm and secretory granules of male accessory glands). Within population character variability is significantly lower in several features of M. carolinensis than in the same characters of the other two species. Similarities as well as differences have been noted in behavioural features and population dynamics between the species.  相似文献   

11.
Macroderoides minutus n. sp. is described based on specimens collected from the Florida gar (Lepisosteus platyrhincus) from Orange Lake, Alachua County, Florida. The new species is the ninth recognized species of Macroderoides and is morphologically closest to Macroderoides flavus and Macroderoides typicus. It differs from both species in having a smaller body, ventral sucker larger than the oral sucker, substantially lower body length to width ratio, fewer and larger eggs, and other characters. A comparison of sequences of nuclear rDNA (partial 18S, complete ITS region, and partial 28S) of the new species, with sequences of 5 other Macroderoides, convincingly supports the status of M. minutus as a new species. Molecular phylogenetic analysis, including all North American Macroderoides species except for Macroderoides parvus, has demonstrated the presence of 2 distinct clades, 1 including Macroderoides spinifer + (Macroderoides minutus n. sp. + Macroderoides texanus) and the other including Macroderoides trilobatus + (M. typicus + M. flavus). The tree topology suggests that the similarity in body proportions among M. minutus n. sp., M. typicus + M. flavus is not a result of close phylogenetic relationship. It has also revealed for the first time the phylogenetic affinities of M. flavus, which is the only North American member of Macroderoides that switched from holostean fishes to teleosts.  相似文献   

12.
Samples of foregut content were collected from 86 macropodid marsupials and examined for the presence of endosymbiotic ciliates. Four host species were examined: Macropus giganteus (eastern grey kangaroo), M. fuliginosus (western grey kangaroo), M. robustus (common wallaroo) and Thylogale billardierii (Tasmanian pademelon). Ciliate morphology was determined by microscopical examination of live and silver-impregnated specimens. Isotrichid ciliates were detected in 51 (59%) of the 86 animals examined. Five new species and one new genus are described. Three of the species belong to the genus Dasytricha Schuberg, 1888: D. dehorityi n. sp. from M. giganteus, D. dogieli n. sp. from M. robustus and D. mundayi n. sp. from T. billardierii. Bitricha n. g. is characterised by the possession of two fields of somatic ciliation, a transverse ventral and a longitudinal dorsal field. B. oblata n. sp. is described from M. giganteus and M. fuliginosus and B. tasmaniensis n. sp. is described from T. billardierii. The occurrence of isotrichid ciliates in both metatherian and eutherian mammals suggests that the family either evolved prior to the divergence of the mammalian lineages or switched hosts from one group to the other following host diversification.  相似文献   

13.
Triteleia peyerimhofficomb. n. (Kieffer, 1906) is redescribed taking into account its great variability and is considered the senior synonym of Triteleia dubia (Kieffer, 1908), Calliscelio lugens (Kieffer, 1910) and Triteleia striolata Kononova & Petrov, 2000, syn. n. Neotypes are designated for Triteleia dubia and Triteleia peyerimhoffi. Triteleia peyerimhoffi is a new record for Greece, France and Croatia and was reared for the first time from eggs of Orthoptera laid in the dead wood of Quercus sp. and Tilia sp. in Romania.  相似文献   

14.
1. Ptilothrix plumata (Hymenoptera) is a neotropical solitary bee that nests in bare, sandy soils. Data on the biology and behaviour of this species are provided. Egg‐to‐adult development time of a neotropical solitary bee and its parasitoids is quantified for the first time. 2. The bee showed huge variability in egg‐to‐adult development time. There are two categories of eggs relative to adult emergence. The same season eggs are those from which adults emerge in the same reproductive season in which the eggs were laid. Adults from next season eggs emerge in the next dry reproductive season. This variability in egg‐to‐adult development time is reached through prepupal diapause. The bee larval parasitoids Leucospis genalis (Hymenoptera) and Anthrax sp. (Diptera) showed similar range in their development times. The data show that diapause is controlled by season. 3. By synchronising adult emergence, this variability in egg‐to‐adult development time facilitates mate finding, and population recruitment is a consequence of the bees avoiding the unfavourable reproductive season.  相似文献   

15.
Tardigrades were sampled from diverse biotypes and classified according to four xeric variables to assess susceptibility to desiccation: exposure to insolation, elevation, and standardized desiccation rate and hydration capacity of the habitat plant. Fifteen tardigrade species were recorded including Hypsibius cataphractus Maucci, a new addition to the British fauna.
Xeric associations with seven tardigrade species were analysed by multiple regression, using incidence and population density as independent abundance estimates. Species show considerable variation in ecotype. The hygrophilic Macrobiotus hufelandi and Hypsibius dujar dini are excluded from rapidly desiccating habitats. Xerophiles, Milnesium tardigradum and H. oberhaeuseri , do not favour high insolation or high desiccation rate but apparently shun poorly drained sites and/ or prolonged hydration. Significant interspecific associations are identified between Milnesium tardigradum and two Hypsibius species which it may exploit for food. Negative associations between three other species— M. hufelandi, M. richtersi and H. prosostomus —suggest competitive exclusion.
The interstitial meiofauna of a dehydrating moss cushion migrates vertically to the proximal C-zone, although this behaviour is not observed in Echiniscus testudo; implications of this for the species' ecotype are discussed.  相似文献   

16.
The genus Monobellu Cassagnau, 1979 (Collembola) is redefined. Four new species and one new subspecies are described from Pyrenees and Cevennes (France) on the basis of labrum morphology, tubercle arrangement on tergites and chaetotaxy of somites: Monobellu culvu sp. n., Monobellu eduphica sp. n., Monobellu grussei minor ssp. n., Monobellu juu sp. n., and Monobellu rousseti sp. n. The subspecies Monobellu grussei dubiu Deharveng, 1986 is reassigned to specific level. A key to the 14 species and subspecies of Monobellu is given. Except M. g. minor ssp. n. which is present in the Pyrenees and the Massif Central and the widespread M. g. grussei (Denis, 1923), all Monobellu species and subspecies are narrow endemics of the Pyrenean range; their distribution is mapped in details. A phylogenetic analysis is performed, taking into account the high level of polymorphism of some characters and the incomplete genetic isolation between certain subspecies, indicated in the field by the presence of narrow hybrid zones. Though obtained under different assumptions and constraints, the most parsimonious cladograms exhibit only slight differences, and the proposed phyletic reconstruction can be considered as robust. It adequately reflects the known distribution of the species in the Pyrenees, it confirms the monophyly of the species M. grussei and supports, in agreement with field distribution data, the idea that reticulate evolution might have occurred in this taxon. © The Norwegian Academy of Science and Letters  相似文献   

17.
Three new species of Huffmanela, here described from eggs only, are reported from the gills of marine fish caught off Nouméa, New Caledonia. Eggs of Huffmanela branchialis n. sp., from Nemipterus furcosus (Nemipteridae), are 45-52 (mean 48) microm in length and 23-30 (mean 25) microm in width, with thin shells. Each egg is enclosed in a thin membrane forming a spindle-shaped envelope 53-85 (mean 63) microm in length. Eggs of H. filamentosa n. sp., from Gymnocranius grandoculis (Lethrinidae), are 48-53 (mean 50) microm in length and 25-30 (mean 27) microm in width, with thin shells. Each egg bears a few long (150 microm), thin filaments. Eggs of these two new species were compared to those of H. paronai Moravec & Garibaldi, 2000, which are redescribed. Eggs of H. ossicola n. sp. were found within the branchial arch bone of Bodianus loxozonus (Labridae) and also filled the spinal chord bone and other bones. This is the first species of Huffmanela reported from bone tissue. Eggs are large, 72-88 (mean 79) microm in length and 32-40 (mean 36) microm in width, with a very thick shell. Each egg is covered with numerous filaments enclosed in a thin envelope. Fresh eggs were unembryonated, but embryos were visible after incubation in seawater. The three new species can be distinguished from other species of Huffmanela by size and the nature of the egg covering. Egg morphology of and their location in the host suggest different life-cycles: those of the first two species (small eggs, thin shells, egg covering possibly favouring flotation) are released from the gill mucosa with the turnover of living tissues and immediately continue their life-cycle, but eggs of H. ossicola (large eggs, thick shell) are only available for the continuation of the life-cycle after the host's death.  相似文献   

18.
ABSTRACT. The morphology, infraciliature, and silverline system of a new marine scuticociliate, Wilbertia typica n. g., n. sp., collected from coastal waters off northern China, were investigated. The new genus Wilbertia is characterized as follows: sculptured and dorso-ventrally flattened body; dominant buccal field that is almost completely surrounded by the paroral membrane; three apically positioned long membranelles, arranged in parallel; membranelle (M)1 and M2 prominent, M3 small; reticulate silverline system. The type species W. typica n. sp. is defined by having a conspicuous anterior beak-like protrusion; five to eight caudal cilia; M1 four-rowed, M2 two-rowed; M3, single-rowed, bipartite; 15 or 16 somatic kineties; contractile vacuole positioned just posterior to the buccal field; globular macronucleus. The small subunit ribosomal DNA sequence of W. typica is 98.5% similar to the similar morphotype, Eurystomatella sinica . Phylogenetic analyses indicate that Wilbertia groups with Eurystomatella sinica forming a branch that diverges at a deep level from all other pleuronematid scuticociliates. The molecular and morphological data indicate that Wilbertia should be placed within the family Eurystomatidae, which is closely related to the well-known Cyclidiidae.  相似文献   

19.
Huffmanela moraveci n. sp. (Nematode: Trichosomoididae) is described from the skin of fins and gills of the silversides Odontesthes smitti Lahille, 1949, and Odontesthes nigricans Richardson, 1848 (Pisces: Atheriniformes), from southwestern Atlantic coast, on the basis of the morphology of adults and eggs found in the host tissues. Huffmanela moraveci n. sp. can be distinguished from Huffmanela carcharini, H. banningi, H. japonica, H. mexicana, H. paronai, H. schouteni, H. shikokuensis, H. branchialis, H. filamentosa, H. ossicola, and H. lata by the size and shape of the eggs. The adult stage of H. moraveci n. sp. can be differentiated from H. hufmani and H. canadensis by the position of the nerve ring and by the total esophagus length/body length ratio. Huffmanela moraveci n. sp. also differs from H. huffmani by the presence of bacillary bands and by the body length. This is the first report of a species of Huffmanela in South America, the first report of a species of Huffmanela with Odontesthes spp. as host, and the third known adult form in the genus.  相似文献   

20.
A new species, Macromotettixoides lativertex Deng et al n. sp. is described with detailed illustrations of external morphology. Comparison between the species M. lativertex n. sp. and allied species is compiled into a table for identification. The distribution and an updated identification key to all known species of the genus is given.  相似文献   

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