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1.
The ventral nerve cord in the family Carabidae (considered in the widest sense! exhibits variations in the degree of fusion of thoracic and abdominal ganglia. There are usually three discrete thoracic ganglia and between one and seven discrete abdominal ganglia, the number differing between tribes. Of the 44 tribes and 177 species examined, 38 tribes contained species showing no differences in the degree of ventral nerve cord consolidation. However, the remaining six tribes showed variations in the degree of ventral nerve cord consolidation between genera (Lebiini, Cychrini, Nebriini, Scaritini, Licinini and Brachinini), whilst one genus showed variations between species (Leistus , Nebriini). No variation in ventral nerve cord consolidation was observed in conspecifics. The degree of ventral nerve cord consolidation is inversely proportional to overall body length. With respect to phylogeny, the degree of consolidation of the nerve cord docs not consistently support the traditional Carabinae-Harpalinae subfamily division. However, the Harpalinae always have four or less discrete abdominal ganglia (with the sole exception of the Broscinij, whilst the Carabinae exhibit almost the whole range of variations. Thus the Harpalinae (or the major pari of it) may be a monophyletic group, but this is not true of the Carabinae. Trends in the degree of ventral nerve cord consolidation for the various tribes were noted, and phylogenetic implications were evaluated wherever possible.  相似文献   

2.
Aims and methods Ground beetle and satellite‐derived land cover data from 1687 United Kingdom 10 km national grid squares were used to assess the relationship between species pool and cover data in Great Britain using fuzzy classification and constrained ordination. Results Ground beetle species pools classified into nine groups which were related to land cover variables using constrained ordination. There was a strong relationship between upland land cover and three ground beetle groups. Deciduous woodland, coastal and tilled land were associated with three other groups. Three further groups did not appear to be strongly associated with any particular cover, but differed in geographical position. Conclusion The distribution of species pools derived from the British national recording scheme at the 10 km scale was strongly related to satellite‐derived land cover data. There appears to be considerable potential for the use of a synthesis of land cover and ground beetle data in the monitoring of environmental change over a large, countrywide, area.  相似文献   

3.
Dalyat mirabilis Mateu 2002 (Coleoptera: Carabidae) is a cave species recently described from SE Spain, which, based on morphological analyses, has been related to the Promecognathinae (with one genus in western North America and four genera in South Africa). In this paper, we investigated the phylogenetic relationships of the main lineages of family Carabidae, and the placement of Dalyat among them, with the 18S rRNA full sequence and a fragment of wingless with the use of parsimony, a fast maximum likelihood algorithm (implemented in the program phyml ), and Bayesian posterior probabilities. Although with wingless alone the relationships of Dalyat were not robustly supported, both with 18S rRNA and in a combined analysis there was a strong support for a sister relationship between Promecognathus and Dalyat with the three methods used. Using a molecular-clock approach the two lineages were estimated to have diverged at a similar (or slightly earlier) age than the origin of Harpalinae, known to have radiated in the Cretaceous. This is compatible with a vicariant origin of the lineage leading to Dalyat because of the isolation of the Iberian plate from Pangea in the late Jurassic to early Cretaceous. Other robust relationships within the Carabidae are the monophyly of Harpalinae (including Morionini, Peleciini and Pseudomorphini), its sister relationship with Brachininae, and the inclusion of these two subfamilies together with Scaritini and the austral Psydrinae in a strongly supported clade (the 'higher' Carabidae).  相似文献   

4.
Abstract. 1. The causes and reproductive consequences of body size variation of Brachinus lateralis Dejean, a parasitic carabid beetle, were investigated.
2. Body size variation occurs within and between sites. Host size has a major influence on body size of the adult.
3. Fecundity is positively correlated with body size. Egg size is not correlated with body size.
4. Mating males tend to be larger than non-mating males. There is a positive correlation of body sizes in mating pairs.
5. Limited opportunity for host choice may maintain size variation despite the advantages of large size.
6. The non-random patterns of mating for a species without obvious intrasexual aggression suggest that subtle means of male-male competition or female choice may be important.  相似文献   

5.
David R. Maddison 《ZooKeys》2014,(416):113-155
Phylogenetic relationships of the Antiperyphanes Complex of the genus Bembidion are inferred using DNA sequences from seven genes (two nuclear ribosomal, four nuclear protein coding, and one mitochondrial protein coding). Redefined subgenera within the complex are each well-supported as monophyletic. Most striking was the discovery that a small set of morphologically and ecologically heterogeneous species formed a clade, here called subgenus Nothonepha. This unexpected result was corroborated by the discovery of deep pits in the lateral body wall (in the mesepisternum) of all Nothonepha, a trait unique within Bembidion. These pits are filled with a waxy substance in ethanol-preserved specimens. In one newly discovered species (Bembidion tetrapholeon sp. n., described here), these pits are so deep that their projections into the body cavity from the two sides touch each other internally. These structures in Bembidion (Nothonepha) are compared to very similar mesepisternal pits which have convergently evolved in two other groups of carabid beetles. The function of these thoracic pits is unknown. Most members of subgenus Nothonepha have in addition similar but smaller pits in the abdomen. A revised classification is proposed for the Antiperyphanes Complex.  相似文献   

6.
7.
External and internal thoracic structures of two carabid species (Trechini) were examined and documented with different techniques. The study has a main focus on the eyeless cave-dwelling specialist Sinaphaenops wangorum, but detailed information is also provided for a species occurring in cave entrances. The phylogenetic background of the structural features of the thoracic skeletomuscular system was addressed. The thoracic morphology of the examined species was compared to conditions observed in previously studied carabids and non-related subterranean leiodids (Staphylinoidea) in order to identify cave adaptations. Main thoracic character complexes linked with cavernicolous habits in Trechini are elongation of the pro- and mesothorax and the legs, and a complete and irreversible reduction of the flight apparatus. The lost flight capacity is linked with a far reaching modification of skeletal elements of the metathorax including a strongly shortened and simplified metanotum, a shortened metaventrite, and completely reduced wings and sclerites of the wing base. The elongate prothorax together with the long and slender head and elongated legs distinctly increases the activity range in the subterranean lightless environment, which likely facilitates foraging of the carnivorous beetles. Some of the observed features like wing loss and elongation of the anterior thorax and legs are also found in some cave-dwelling Leiodidae (Leptodirini), whereas some other subterranean members of the staphylinoid family have a compact body and legs of normal length. In contrast to the predaceous Trechini, Leptodirini are scavengers.  相似文献   

8.
Putchkov A 《ZooKeys》2011,(100):503-515
A review of the ground beetles of the Ukrainian fauna is given. Almost 750 species from 117 genera of Carabidae are known to occur in the Ukraine. Approximately 450 species of ground beetles are registered in the Carpathian region. No less than 300 species of ground beetles are found in the forest zone. Approximately 400 species of Carabidae present in the forest-steppe zone are relatively similar in species composition to those in the forest territories. Some 450 species of Carabidae are inhabitants of the steppe zone. Representatives of many other regions of heterogeneous biotopes such as forest, semi desert, intrazonal, etc. can be found in the steppe areas. The fauna of Carabidae (ca. 100 species) of the lowlands of southern Ukraine (sandy biotopes), situated mostly in the Kherson region, is very peculiar. The fauna of the Crimean mountains contains about 300 species. Conservation measures for the Carabidae are discussed.  相似文献   

9.
The role of the ventral nerve cord has been investigated in Lithobius forficatus L., using ganglionic destructions, ganglionic implantations and ganglionic electrostimulations. It seems that a stimulating principle is present in the sub-oesophageal ganglion. Its action is not so important as that of the pars intercerebralis.  相似文献   

10.
A survey of invertebrates on exposed riverine sediments (ERS) in four catchments of rivers in Scotland and northern England was carried out in 1996 and 1997 using pitfall traps. The resulting 179 lists of ground beetle species were used in ordination and classification analyses to determine the different types of habitats and the environmental factors influencing species assemblage distribution. Types of ERS habitat differed between highland and lowland catchments; there were also different numbers of habitat types in each catchment. The distribution of ERS within catchments was related to geology, position in catchment, sediment composition and the amount of vegetation. Evidence of the positive nature of river engineering was identified and the role of river management is discussed. The numbers of nationally rare and scarce ground beetle species recorded from the ERS habitats in each catchment are reported and the factors affecting their distribution discussed.  相似文献   

11.
12.
This study presents qualitative and quantitative research on communities of ground beetles (Carabidae) occurring in 2001 and 2003 in three types of habitats located near Bydgoszcz city, Poland (UTM CD19), on the Vistula river floodplain: elm and ash riparian forest (RF), poplar monoculture (P), and unintensively-farmed meadows (M). During both studied years 57 species of ground beetles were found in riparian forests (RF), 56 species in plot P and 47 in plot M. In 2001 from all sample plots 3845 beetles were collected; in 2003- 9589. In both years most specimens came from plot RF (3123 in 2001 and 6224 in 2003). From plot P 2656 specimens of ground beetles were collected and from plot M 1430 specimens. Statistically significant differences were found in the abundance of Carabidae, among sampling areas and the years of study.  相似文献   

13.
大步甲主要分布于北半球,全世界大约有1000余种。因大步甲后翅退化,不能飞行,其移动能力和扩散范围都受到很大程度的限制,因此,容易产生地理隔离和遗传分化,从而成为研究物种分化和生物多样化的好材料。近年来,通过对大步甲分子系统的详细研究,不仅很大程度上解明了大步甲各分类群间的系统发育关系,而且对大步甲的系统演化过程和形态进化模式也有了较深的理解,获得了很多重要的见解。在此做一个简单的综述。  相似文献   

14.
15.
Abstract. 1. Carabid beetles were sampled by means of pitfall traps on several clearcut areas and in adjacent forests.
2. A hierarchical analysis of diversity revealed a significant increase in the within-genus component of species diversity after forest cutting.
3. This trend in intrageneric diversity was obscured, with respect to total species diversity, by a nonsignificant reduction in diversity at the generic level.
4. The increase in the within-genus component of species diversity following forest cutting was consistent with the hypothesis that disturbance of a cornmunity can disrupt processes of competitive exclusion.  相似文献   

16.
As compared to natural forests, managed boreal forests are younger, more homogeneous in terms of tree age and species composition, and consist of smaller fragments. Here we examine the effects of such characteristics caused by forestry on carabid beetles (Coleoptera, Carabidae) in the boreal region. The main results are the following. (1) Fragmentation of forests and the size of a fragment appear not to be crucial for the survival of the majority of forest carabids, as they tend to be distributed over various successional stages, but species requiring old-growth habitats suffer. (2) For carabids there appear to be no or very few edge specialist species, and forest-open land edges appear to be effective barriers for species associated with forest or open habitat. However, generalist species easily cross the edge, and edges of forest fragments may be invaded by species from the surrounding open habitat. (3) Habitat change following clear-cutting dramatically changes the composition of carabid assemblages: species restricted to mature forests disappear and open-habitat species invade, while habitat generalists survive at least in the short term. Carabid diversity can probably best be maintained if forest management mimics natural processes, maintains natural structures and includes the natural composition of vegetation and other structural elements (such as dead wood) within the stands, provided that these forest features can be maintained and recreated through forest management practices. At a larger scale, the whole spectrum of forest types and ages (especially old-growth forests), and different successional processes (especially fire) should be maintained. These require the development and use of innovative logging methods, and the planning, implementation, and assessment of landscape-scale ecological management strategies.  相似文献   

17.
The pattern of localization of the ribosomal genes was studied by means of fluorescence in situ hybridization in 39 species of the tribe Harpalini. Most of them show one pair of autosomes carrying the ribosomal genes in a distal position of a single chromosome arm. This pattern is hypothesized to be ancestral for the whole tribe. Both, chromosome number and the number and localization of rDNA loci, show little variation and are therefore of little phylogenetic value. Only in the subtribe Ditomina is there enough variation to characterize phyletic relationships. The stability of rDNA loci is even higher than the constancy of chromosome number, as most species of Ditomina (genera Dixus, Eocarterus, Carterus, Odontocarus and Ditomus) have the usual pair of autosomes with rDNA loci, in spite of remarkable differences in the diploid number. Only Dixus sphaerocephalus and Dixus clypeatus have two autosomal pairs with a fluorescent signal. These results do not support the hypothesis that the high chromosome numbers found within Ditomina are the result of polyploid change from the ancestral 2n = 37 karyotype of the tribe Harpalini. Chromosomal translocations or the presence of mobile genetic elements are plausible sources of the few cases of intraspecific polymorphism in the rDNA loci found in species of Harpalus.  相似文献   

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19.
A review of data on the background of wing dimorphism in carabid beetles (Coleoptera: Carabidae) and especially of the closely relatedCalathus cinctus andC. melanocephalus is given. In bothCalathus species wing dimorphism is inherited in a simple Mendelian fashion with the brachypterous condition dominant, but inC. melanocephalus the expression of the long winged genotype is under environmental control as well. The development of long winged phenotypes in the latter species is favoured by relatively favourable environmental conditions, such as high temperatures and a high food-supply. The higher fecundity of the larger and heavier long winged females of both species may compensate for losses of long winged phenotypes by flight activities. The evolutionary significance of both types of inheritance is discussed in relation to dispersal. The ‘fixed type’ as found inC. cinctus is considered an opportunistic short term ‘between sites strategy’, whereas the ‘dynamic type’ ofC. melanocephalus represents a flexible long term ‘within sites strategy’.  相似文献   

20.
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