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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

Evaporative cooling, through moistening of the eyes, panting, urinating and salivating, takes place in the spurred tortoise at high ambient temperatures. The mean temperature at which thermoregulatory salivation is initiated (39·5° ± 0·4°C) is constant, irrespective of body size, but the rate of panting is slower in heavier tortoises. Very small tortoises, however, do not pant for more than a few seconds.

Tortoises are inactive at 13°C and their body temperatures do not vary from the ambient. At 21° and 26°C, heat loss through transpiration exceeds metabolic heat production: at 33°C body temperatures are higher than the ambient. Increased range and variability at higher temperatures may be explained by the fact that spurred tortoises hold their breaths for long periods—a mechanism that could serve to reduce respiratory water loss. When breathing is actually taking place, however, the rate of respiration depends on body temperature: this grades into panting above 35°C.  相似文献   

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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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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

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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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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《Journal of Natural History》2012,46(15-16):951-971
The larva, nymphal stages and adult of Hydrozetes longisetosus sp. nov. are described and illustrated, and the relationship of this species with the other European species of Hydrozetes is investigated. This species was first found at the edge of a forest lake, Dury 3, in the Tuchola Forest (Poland). Subsequently, we studied specimens that had been collected in 1976 by Dr H.M. Engelmann 40 km north of Görlitz Niederspree (Germany). Many adults of this species have three setae of the c‐series, which is rare in Hydrozetes and is considered a primitive character. Most adults have two pairs of p‐series setae, which is not common in Brachypylina and is unique among European Hydrozetes. The nymphal stages have many long setae in the marginal part of the gastronotum (whole l‐ and h‐series and seta p 1), and some or all long setae of the c‐ and d‐series, which is unique among European Hydrozetes. In H. longisetosus neotrichy occurs in the h‐series, as in H. parisiensis Grandjean, 1948 Grandjean, F. 1948. Sul les Hydrozetes (Acariens) de l'Europe occidentale.. Bull Mus Natl Hist Nat Série 2., 20: 328335. French [Google Scholar]. Therefore, the former species is closely related to the latter, and also to H. lacustris (Michael, 1882) and H. octosetosus Willmann, 1932 Willmann, C. 1932a. Oribatiden aus dem Moosebruch.. Archiv Hydrobiol., 23: 333347.  [Google Scholar], which rarely retain all the c‐series setae in the adults.  相似文献   

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Since the pioneering works of the Norwegian biologist G.O. Sars, little attention has been given to the freshwater harpacticoids in Norway. The prime purpose of this paper is to present the state of current knowledge about the Norwegian freshwater harpacticoid fauna based on all known published and unpublished literature and archive material. We highlight the contribution of G.O. Sars to the knowledge of this group by presenting his remaining unpublished archive material. We present two Norwegian species checklists – one for freshwater harpacticoids (16 species) and another for freshwater-associated/brackish-water harpacticoids (nine species). Four of the freshwater harpacticoid species are described by G.O. Sars. Original unpublished plates with drawings of those species are included in the paper. In addition, an overview of species distributions throughout the country is given.  相似文献   

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《Journal of Natural History》2012,46(37-40):2537-2542
The earliest report on radiolarians from the Arctic Ocean (north of the Arctic Circle) was provided by H. B. Brady (1878 Brady, H. B. 1878. On the reticularian and radiolarian Rhizopoda (Foraminifera and Polycystina) of the North‐Polar Expedition of 1875–76.. Annals and Magazine of Natural History, Series 5, 1: 425440. [Taylor & Francis Online] [Google Scholar]). He documented the occurrences of 10 genera from soundings in northern Baffin Bay and north of Greenland, but he did not illustrate any specimens in his report. We have re‐examined Brady's original slide collection, housed at the Natural History Museum, London (NHM), in order to refine his radiolarian identifications to species level. We have identified 11 radiolarian taxa in his slides, but some are definitely more characteristic of tropical oceans rather than high northern latitudes. We conclude that this is most likely due to sample contamination or misidentification of samples. Therefore, the actual occurrence of tropically affiliated radiolarians recorded from the Arctic is uncertain and should be regarded with suspicion.  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   

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Two akanthophoreid taxa, Chauliopleona and the new genus Saurotipleona, are modest contributors to tanaidacean diversity in the benthos of seas from Iceland to the British Isles along the ‘Atlantic Margin’. Three of H.J. Hansen’s ‘Ingolf’ species, originally within the genus Leptognathia, are rediagnosed, i.e. Chauliopleona amdrupii, C. armata and C. hastata. One new species, C. bamberi, from British waters is described and a new genus and species, Saurotipleona julii, is described from bathyal depths in the Irminger and Iceland basins. The latter is similar to Chauliopleona in having a sternal spur on pleonite-5 but this is of a slightly different form and is ventrally directed; it also has two superodistal spines on the propodus of pereopod-5, a distinctly plesiomorphic character in the family. A distribution map and key to the identification of these species are given.

http://zoobank.org/urn:lsid:zoobank.org:pub:E7EF8C72-D1C6-438E-B9C2-A5CE637FB75A  相似文献   

18.
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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