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Summary

The flowers, fruit and seed of Dracontomelon costatum Blume are here described for the first time. It is remarkable in that four of the five carpels present in the flower are suppressed during fruit development. Information concerning habit and habitat is also included.  相似文献   

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Summary

A key to the beetles of the 33 families of Heteromera (Cucujoidea) is presented for the world and a summary of about 67 imaginal characters (where known) for each family is also included. The key is intended not only for those who wish to identify beetles with heteromeroid aedeagi but also for those who want to learn the existing gaps in our knowledge on this subject and problems for future researches. Sincere efforts to distinguish or discover the primitive and derivative characters and groups for all families of beetles (Coleoptera including Strepsiptera) are urgently required.  相似文献   

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Summary

The families Opecoelidae, Lepocreadiidae and Enenteridae are differentiated. The Enenteridae is considered to consist of three subfamilies, the Enenterinae, the Cadenatellinae subfam. nov. and the Pseudolepidapedinae, whose constituent genera are listed. The diagnostic features of the opecoelid subfamilies Opecoelinae, Plagioporinae and Stenakrinae are presented. Plagioporus is restricted to freshwater forms, and Lebouria is considered a synonym of Peracreadium, following the transfer of L. idonea Nicoll, 1909, to the latter genus as P. idoneum comb. nov. Caudotestis is considered to belong to the Stenakrinae, Trematichtys to the Allocreadiidae, Spinoplagioporus to the Enenterinae and Pycnadenoides to the Plagioporinae. Macvicaria gen. nov., with the type-species M. [Plagioporus] alacris (Looss, 1901) and also containing M. [Distoma] soleae (Dujardin, 1845) (syn. Plagioporus varius) is erected for some of the marine forms previously allocated to Plagioporus. Neolebouria is briefly discussed and N. merretti sp. nov. from Bathytyphlops sewelli is described. Gaevskajatrema gen. nov. is erected for type-species G. [Peracreadium] perezi (Mathias, 1926) and G. [Plagioporus] lethrini (Nagaty, 1942). Podocotyle is discussed, especially in relation to P. angulata (Dujardin, 1845), which is reinstated as the type-species, P. atomon (Rud., 1802) and P. staffordi Miller, 1941, and P. abitionis McFarlane, 1936, is transferred to Pellamyzon. Tellervotrema gen. nov. is erected for the type-species T. armstrongi sp. nov. from Nezumia aequalis, which is described, and T. [Plagioporus] beringi (Mamaev, 1965). The genera Peracreadium, Cainocreadium, Hamacreadium, Bathycreadium and Helicometra are also briefly discussed. In addition, a key to the plagioporine genera occurring in European Atlantic waters is presented.  相似文献   

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The taxa centering around Phlox austromontana Coville are revised. Named as a new variety is P. austromontana var. lutescens Welsh from eastern Garfield County, Utah. A new combination is provided as P. austromontana var.  jonesii (Wherry) Welsh.       相似文献   

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Summary

Observations on the vertical distribution of earthworms in pasture confirm that Allolobophora longa, A. rosea and Lumbricus terrestris are relatively deep burrowers, and that the adults of these species burrow deeper than juveniles. Deep burrowing species have more elongated bodies than surface dwellers such as Dendrobaena mammalis and L. castaneus, and adults have more elongated bodies than juveniles. Long-bodied species tend to have more segments than short-bodied ones. On the limited evidence available, increase in relative thinness with age is not, apparently, associated with increased number of segments in A. rosea or L. terrestris but is in A. caliginosa and A. longa, and to a lesser extent in A. chlorotica. In adults and juveniles the diameter of the anterior region is greater than that of the posterior region of the body, and the latter is more strongly flattened dorsoventrally than the former. Such morphological differentiation is consistent with the differences in function of the anterior and posterior regions indicated by a simple model of earthworm locomotion. From the model it can be concluded that short-bodied earthworms will take relatively longer ‘steps’ when moving on the surface than will long-bodied ones, and that earthworms with relatively large anterior segments will take longer ‘steps’ than those with relatively small ones. This is in line with the results of observations on living earthworms. The mechanism of locomotion is just one of many factors influencing earthworm size and form. Others include feeding mechanics, vulnerability to predation and desiccation, and exposure to anaerobic conditions.  相似文献   

11.
Osteochilotrema malayae gen. nov. sp. nov. (Osteochilotrematinae subfam. nov.) from the intestine of Osteochilus hasselti in Malaysia is described. It is characterized mainly by the symmetrical extracaecal testes and the structure of the male terminal ducts. Protocladorchis pangasii is reported from Pangasius pangasius, Barbus daruphani, B. tambroides and from Malaysia for the first time. It is redescribed and the generic diagnosis amended. Helostomatis indica is reported from O. hasselti in Malaysia, both new records. The subfamily and generic diagnoses are amended. Orientodiscus jumnai was recovered from new hosts, B. tambroides and P. micronemus, and is new for Malaysia.  相似文献   

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Summary

The life history of the African grasshopper Ornithacris turbida (Walker) was studied under controlled laboratory conditions. No phase variation was observed between isolated and crowded stock in respect of colour, morphometrics, weight of hatchlings or fledglings. All the females reared in isolation Had seven nymphal instars but in the case of the isolated males the majority had six but some had seven nymphal instars. This variation was also observed in the crowded stock for both males and females.

In isolation the mean nymphal life of 15 females was 78·7 ± 3·2 days, the mean for nine males having six instars was 59·9 ± 3·2 days and for five males having seven instars the mean nymphal life was 74·6 ± 3·8 days. Overall the nymphal life for the insects reared in crowds was slightly shorter, but no attempt was made to separate the insects having six or seven instars.

The stripes in the compound eye correlated with the number of nymphal instars. Colour changes in the compound eye coincided with overall body colour changes and maturation.

The mean maturation period of females reared in isolation was 101 days, varying from 72 to 158 days. The mean maturation period of the crowded females, estimated by the collection of the first egg-pod, was 73 days with a range of 62 to 84 days; when estimated by the collection of egg-pods averaging one per female it varied with the cage from 91 to 114 days. This suggests that maturation in the crowded females was quicker.

The isolated females lived longer than ones reared in crowded conditions, and laid more egg-pods. There was, however, no difference in the number of eggs per pod or their hatchability between crowded and isolated stock. In both cases 76% of the total number of eggs hatched. Hence overall the isolated females had a greater fecundity than those reared in crowds.

The average weight of a single hopper from isolated parents was 15·5 mg and that from crowded parents was 14·0 mg.  相似文献   

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Summary

  • 1. A morphological study of five body regions of the Lepidoptera has been made, these being (a) the radial system of the mesothoracic wing, (b) the mesothoracic sternopleural region, (c) the ventral thoraco-abdominal articulative (and adjacent) structures, including the integumental components of the tympanum where present, (d) the dorsal thoraco-abdominal articulation, etc., and (e) the metathoracic furca or endosternite. These regions were selected because the nature of the variation they exhibit suggested that, of the much larger number of regions primarily investigated, they are the most likely to provide information on the evolution of the higher taxa in the order. None of these regions had been investigated at all fully previously, and therefore a considerable amount of basic morphological study was necessary as a preliminary to phylogenetic discussion. This morphological work has been extended to include the primitive Lepidoptera (with the Trichoptera) in the case of the mesosternopleural region, and in the regions of thoraco-abdominal articulation, in order to clarify basic homologies where these were obscure in the Ditrysia.

  • 2. Included also in the preliminary morphological treatment are two other body regions, the variation of which is not complex, and can be more briefly described. These regions are the prothoracic sclerites and the metanotal subdivisions—both of these showing interesting variation throughout the order which can be easily interpreted from the phylogenetic standpoint.

  • 3. Following reference to the basic morphology of each region studied, a broad outline of the evolutionary dynamics of each character complex is given in order to provide a basis for discussion of the evolutionary trends manifested within the superfamilies.

  • 4. In sections four and five of this work, the character complexes which were the subject of morphological study earlier are examined further with regard to their dynamics as manifested within each of the Ditrysian superfamilies. The formation of the concepts which are outlined here is based on consideration of all information derivable from all of these character complexes along with previously published information on other aspects of Lepidopterous anatomy. Resulting from this, a re-organization of the superfamilies has been possible on a phylogenetic basis. The chaotic state of the past literature on the classification of the Lepidoptera, the result of superficial taxonomic work, renders the comparison of the present system with previous ones clearly impossible within the scope of the present paper, but it is noted that many of the superfamily groupings do not differ very widely from those in some of the more comprehensive early studies, such as Forbes (1923). Through lack of material, no radical re-organization of the primitive Ditrysian superfamilies included in the Tinaeoid complex has been attempted, and for the same attempting to convey a very great deal of information by means of varied labelling of the two components of the suture. Reference both to the text, and to the figures given in the introductory (morphological) section of this paper, should however, enable anyone to appreciate these factors from the figures given. (3) Abbreviations used with reference to wing veins and pupal tracheae follow the standard Comstock-Needham system, apart from the identification of Cu2, which follows Tillyard's (1969) interpretation.

Note also that a few of the less common structures have been explained with the captions to the figures.  相似文献   

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Summary

The African Ctenidae in the Collections of the British Museum (Natural History) are revised. Thirty species are contained in the subfamilies Cteninae and Acantheinae. Ctenus batesii Pocock, 1903, is a synonym of Ctenus capulinus (Karsch), 1879, Ctenus dirus Thorell, 1899, is a synonym of Ctenus kingsleyi F. O. P.-Cambridge, 1898, Ctenus marshalli F. O. P.-Cambridge, 1898, is a synonym of Ctenus melanogastra (Bösenberg & Lenz), 1895, and Ctenus spenceri F. O. P.-Cambridge, 1898, is a synonym of Ctenus pulchriventris Simon, 1896.

The subfamily Acantheinae is recorded from Africa for the first time. A new genus, Africactenus, is erected for a group of allied species. The genotype is Ctenus agilior Pocock, 1899, and the following new species are described:—A. depressus, A. desartsi, A kribiensis, A. pococki, A. sandersoni, A. simoni, A. sladeni, A. tridentatus and A. trilateralis. Ctenus longurio Simon, 1909, is transferred to the genus Africactenus on examination of the type-material.

Certain species from the Simon Collection are listed in the Appendix and figured for the first time.  相似文献   

18.
The uncontrolled, global increase in atmospheric CO 2 concentration (ca 80 ppmv) and decline in δ 13 C air (ca 1.5%) since industrialization provide experimental boundary conditions by which to assess physiological response of vegetation. To examine consequences of these global atmospheric changes in the southwestern U.S., 350 specimens of Atriplex confertifolia, A. canescens, Ephedra viridis, Pinus edulis, P. flexilis, Juniperus scopulorum, and Quercus turbinella of precisely known age spanning the last 150 years were acquired from 9 herbaria. Cellulose analysis of δ 13 C plant and estimation of isotopic discrimination (Δ) permitted calculation of water-use efficiency (A/g). The δ 13 C plant chronologies of C 4 Atriplex spp. show some promise as a reliable proxy for δ 13 C air because their mean trends approximate the known δ 13 C air chronology. However, the high variability would necessitate multiple samples at any time period to accurately represent the mean. The generally increasing A/g trends of the 5 C 3 species are particularly pronounced for P. edulis and, after the 1950s, for J. scopulorum, but less evident for P. flexilis, E. viridis, and Q. turbinella, evidencing possible differences in species response to rising CO 2 concentrations. The trends are statistically noisy, however, possibly due to complex microclimates, extreme seasonality, and great interannual variability typical of the southwestern U.S. Herbarium specimens, at least in the Southwest, may be less useful for precise detection of direct CO 2 effects on plant physiology than tree rings, where the variability can be constrained to a single individual over time.  相似文献   

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Abstract

Parapsyllaephagus Adulticolus Robinson (CHALCIDIDAE: Encyrtinae) is an endoparasite of the adults of Psylla melanoneura Förster and Psylla subferrigenea Edwards. The life histories and biology of the hosts and parasite are described. Parapsyllaephagus adulticolus has five larval instars, which feed selectively upon the developing internal genitalia of the host at first, and eventually, as the final instar, upon the whole of the abdominal viscera. Pupation within the psyllid is followed by emergence of the adult parasite through the posterior dorsal surface of the abdomen of the host. The effect of these activities upon the migration of the adult psyllid from a winter shelter plant to a summer host plant is discussed and a relationship between the stimulus to migrate and the state of development of the internal genitalia is postulated. Some aspects of the orientation of the parasite larva within the host and the phenomenon of larval reversal are discussed.  相似文献   

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Multiple surveys carried out by herpetologists in México, D.F., during the 1980s failed to find specimens of Aspidoscelis septemvitatta (Squamata: Teiidae). However, 10 specimens were recently collected to the east of México, D.F., inside a protected area, Sierra de Santa Catarina. The Sierra de Santa Catarina has been heavily modified by human activity and habitation. Morphological and natural history information about the specimens are presented, as well as notes on locality.  相似文献   

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