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1.
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   

2.
3.
The shallow-water tanaidacean fauna of the Bass Strait has been the subject of recent intensive studies. The present paper extends this work into the deeper waters of the region, describing two new species and one new genus. The new species of the genus Paradoxapseudes has a combination of three maxillule palp setae, no plumose setae on the basis of pereopod 1 nor proximal serration on the antennal peduncle. The second species represents a new genus of the family Anarthruridae, having six marginal setae on the third maxilliped palp article and spines on the merus and carpus of the anterior pereopods. The high diversity of Tanaidacea in Australian waters is discussed. In particular, we conclude that Australian coasts suffer a diversity of immigration routes, have sufficient marine longevity, and afford such a diversity of available niches to have allowed multiple colonization and subsequent allopatric speciation of Tanaidacea. http://www.zoobank.org/urn:lsid:zoobank.org:pub:EE309A5A-E06D-416F-95BD-4C8D0D2BEB97  相似文献   

4.
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   

5.
6.
We examined 590 specimens of Reithrodontomys from 95 localities in the state of México. Four species of the subgenus Reithrodontomys and 1 of the subgenus Aporodon were identified. The former subgenus included R. chrysopsis , R. sumichrasti , R. megalotis , and R. fulvescens , which has 2 subspecies— R. f. toltecus and R. f. mustelinus — in the state. The representative of the subgenus Aporodon is R. microdon wagner , which is recorded for the first time in the state. We give information on taxonomy, morphometrics, reproduction, habitat characteristics, and related fauna. A discriminant analysis correctly classified 100% of specimens from the 6 taxa with 5 canonical variates, and accounted for 96.1% of the variance with the first 3 canonical variates.  相似文献   

7.
Summary

Eleven species from the shallow water of the Gálapagos are recognized. Of these, two are also found on the Pacific coast of Central America and one occurs in the Caribbean region. Eight species appear to be endemic, of which five are described as new: Anoplodactylus torus, Ammothella dawsoni, Eurycyde encantada, Rhynchothorax barnardi, Tanystylum distinctum. A deepwater species, Ascorhynchus laterospinum Hilton, is redescribed. The pycnogonid fauna shows close relationship to that of mainland Central America, but does not suggest insular speciation on the basis of the collections studied. Indo-Pacific representation is lacking in the material studied.  相似文献   

8.
《Journal of Natural History》2012,46(41-44):2569-2620
The aim of this paper is to revise populations of Macrothrix cf. hirsuticornis (Cladocera: Anomopoda: Macrothricidae) from different regions of the southern hemisphere. It is demonstrated that M. hirsuticornis Norman and Brady, 1867 Norman, A. M. and Brady, G. S. 1867. A monograph of the British Entomostraca belonging to the families Bosminidae, Macrothricidae and Lynceidae.. Natural History Transactions of Northumberland and Durham, 1: 354408.  [Google Scholar] s. str. is absent there, and five related species occupy different Subantarctic islands and the southernmost portions of South America, and Africa. Macrothrix boergeni Studer, 1878 Studer, T. 1878. Beiträge zur Naturgeschichte wirbelloser Tiere von Kerguelensland.. Archiv für Naturgeschichte, 44: 102121.  [Google Scholar] from the Kerguelen Archipelago is redescribed and a neotype is selected. All populations in the southernmost portion of continental South America, Tierra del Fuego, Falklands, South Georgia, South Orkney Islands, and on the Antarctic Peninsula belong to M. oviformis Ekman, 1900 Ekman, S. 1900. Cladoceren aus Patagonien, gesammelt von der schwedischen Expedition nach Patagonien 1899.. Zoologische Jahrbücher, Abteilung für Systematik, Geographie und Biologie der Tiere, 14: 6284.  [Google Scholar]. All the taxa described from this region—M. ciliata Vávra, 1900 Vávra, W. 1900. “Süsswasser‐Cladoceren. Ergebnisse der Hamburger magalhaensische Sammelreise 1892/93. II Band. Arthropoden.”. In Hamburg 125.  [Google Scholar], M. odontocephala Daday, 1902 Daday, E. 1902. Mikroskopische Süsswasserthiere aus Patagonien, gesammelt von Dr. Filippo Sylvestri.. Természetrajzi Füzetek, Budapest, 25: 201310.  [Google Scholar], M. propinqua Sars, 1909 Sars, G. O. 1909. Fresh‐water Entomostraca from South Georgia.. Archiv for Mathematik og Naturvidenskab, 30: 135.  [Google Scholar], and, probably, M. inflata Daday, 1902 Daday, E. 1902. Mikroskopische Süsswasserthiere aus Patagonien, gesammelt von Dr. Filippo Sylvestri.. Természetrajzi Füzetek, Budapest, 25: 201310.  [Google Scholar]—are junior synonyms of M. oviformis. Two new species are established: M. sarsi sp. nov. from the Cape region of South Africa and M. ruehei sp. nov. from Crozet, Marion islands, and Île Amsterdam. Macrothrix cf. flagellata Smirnov and Timms, 1983 Smirnov, N. N. and Timms, B. V. 1983. A revision of the Australian Cladocera (Crustacea).. Records of the Australian Museum, Supplement, 1: 1132. [Crossref] [Google Scholar], previously known only from Tasmania, is found on Macquarie Island too. Differences between species from the southern hemisphere and Palaearctic M. hirsuticornis are summarized. It is demonstrated that characters of the general body shape (i.e. presence of a hood or a tooth on posterior head border) have a limited value for the systematics of Macrothrix. In contrast, some fine details, mostly missed by previous authors, are valuable for species discrimination. The present study increases the number of species recorded from the Antarctic‐Subantarctic region. Probably, the current pattern of Macrothrix distribution results from a disruption of a pan‐continental (early Mesozoic?) species complex.  相似文献   

9.
10.
Bahadzia setimana sp. nov. from South Andros, and B. obliqua sp. nov. from Cat Island, both in the Bahamas, are described. The recently described genus Bahadzia now contains five closely related taxa, each apparently confined to a single island or isolated group of islands, in a restricted area of the West Indies, ranging from Haiti in the south to the northern Bahamas.

The present discoveries show not only that low-salinity groundwaters of the West Indies have a marked degree of insular endemism, but that the high-salinity anchihaline habitats possess endemics in certain groups as well.

Current models which seek to explain the evolution of stygobionts on Atlantic Islands are reviewed critically and the most likely synthesis is provided.  相似文献   

11.
Genera assigned to the cheilostome bryozoan family Onychocellidae are revised based on the skeletal morphology of the type species and, when possible, the type material of these species. All genera are illustrated using scanning electron micrographs, some for the first time. Onychocellidae, which ranges from the Cenomanian stage of the Cretaceous to the Recent, has been a particularly troublesome family because of poorly defined generic concepts correlating at least in part with a paucity of morphological characters. Thirty-five genera are described in this review. Of these, two are recognised as subjective synonyms of other onychocellid genera (Rhebasia and Semieschara), one cannot be sufficiently characterised from the type material (Collura), and two are new: Aechmellina gen. nov. (type species Aechmella falcifera) and Kamilocella gen. nov. (type species Eschara latilabris). A neotype is chosen for Rhagasostoma hexagonum, the type species of Rhagasostoma. A key is provided to assist in the identification of onychocellid genera. Phylogenetic relationships between genera remain obscure and are unlikely to be fully resolved based on skeletal morphology alone. The family as an entity is loosely circumscribed and almost certainly paraphyletic, containing stem genera of other anascan familes such as Lunulitidae, Coscinopleuridae and Aspidostomatidae.

www.zoobank.org/urn:lsid:org:pub:63A31AD2-F049-42CB-A45B-557014DC286E  相似文献   


12.
The West Palearctic species of Rhoptromeris are revised. A total of 11 species are recognised as valid in this region, including four newly described species: Rhoptromeris dichromata sp. nov., Rhoptromeris koponeni sp. nov., Rhoptromeris leptocornis sp. nov. and Rhoptromeris macaronesiensis sp. nov. Eucoila luteicornis Ionescu, 1959 is synonymised with Rhoptromeris heptoma (Hartig, 1840) syn. nov. A checklist of the Holarctic Rhoptromeris is presented and an identification key to the West Palearctic species is provided. www.zoobank.org/urn:lsid:zoobank.org:pub:8164332C-93E2-4E3F-A408-F5FF5DFB366E  相似文献   

13.
14.
《Journal of Natural History》2012,46(15-16):1093-1120
During the study of rich material collected in the USA, six Zerconidae species were found which seem to belong to the genus Amerozercon Hala?ková, 1969 Hala?ková, V. 1969. Some new species of the family Zerconidae from North America (Acari: Mesostigmata). Acta Soc Zool Bohem, 33: 115127.  [Google Scholar]. Four of them, Amerozercon annularis sp. nov., Amerozercon auricularis sp. nov., Amerozercon halaskovae sp. nov. and Amerozercon penicillatus sp. nov. proved to be new to science. The unknown female of the type species of the genus, Amerozercon suspiciosus Hala?ková, 1969 Hala?ková, V. 1969. Some new species of the family Zerconidae from North America (Acari: Mesostigmata). Acta Soc Zool Bohem, 33: 115127.  [Google Scholar], is described. Amerozercon minimus (Sellnick, 1958) is redescribed and transferred from the genus Zercon C. L. Koch, 1836 to Amerozercon. Some remarks on the problems of the present Zerconidae systematics are discussed.  相似文献   

15.
16.
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   

17.
This paper presents the results of a study performed in eight caves located in the area of the Kraków-Cz?stochowa Upland. In total, 586 samples (400 cm3 each) were taken from the caves and sites located up to one metre from the main entrances of the caves. Of 109 species belonging to 13 families that were identified, four were species new for Polish fauna. In this study, cluster analysis and correspondence analysis were used to compare the species composition of mite communities living in the caves and their immediate surroundings. We also examined the possibility of isolating troglophilic species based on IndVal analysis. Those results showed distinct differences between Gamasina mites living in two distinct habitats. We also established indicator species for the examined caves.  相似文献   

18.
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   

19.
The present study summarizes additions to the known fauna of Eucharitidae of Saudi Arabia. Cherianella arabica Gadallah &; Soliman sp. nov. and the male of previously known female Eucharis (Psilogastrellus) albipennis Bou?ek, 1956 are described and illustrated. Three new records are also added to the fauna of Saudi Arabia: Eucharis (Eucharisca) intermedia Ruschka, 1924, Eucharis (Psilogastrellus) acuminata Ruschka, 1924 and Eucharis (Psilogastrellus) punctata Förster, 1859.

http:/zoobank.org/urn:lsid:zoobank.org:pub:F1B1C493-AA83-4696-AF8B-3B3F62C09B41  相似文献   

20.
《Journal of Natural History》2012,46(5-8):401-417
Four species of Caligus, with two new species, are reported from five species of marine fishes of Taiwan. They are: Caligus arii Bassett‐Smith, 1898 Bassett‐Smith, P. W. 1898. Further new parasitic copepods found on fish in the Indo‐tropical region.. Annals and Magazine of Natural History (Series 7), 2: 7798. [Taylor & Francis Online] [Google Scholar] on the body surface of Trichiurus lepturus Linnaeus, Caligus dasyaticus Rangnekar, 1957 Rangnekar, M. P. 1957. Caligus dasyaticus sp. nov. and Caligus dussumieri sp. nov., (Copepoda) parasitic on Bombay fishes.. Journal of the University of Bombay, 25: 1622.  [Google Scholar] on the body surface of Dasyatis navarrae (Steindachner), Caligus dactylus n. sp. on the gill filaments of Dactyloptera peterseni (Nyström), and Caligus lutjani n. sp. in the oral/gill cavities of Lutjanus argentimaculaltus (Forsskål) and Lutjanus bohar (Forsskål). Both C. arii and C. dasyaticus are reported for the first time from Taiwan. Caligus dactylus differs from its congeners by the possession of the following combination of features: large myxal process on the maxilliped; a pair of parallel tines on the sternal furca with truncate tip; simple elements (without accessory process) at the tip of leg 1 exopod; and an armature formula of I‐0; I,III on leg 4. Caligus lutjani is distinguished by carrying a two‐segmented abdomen; a pair of diverged tines on the sternal furca with acute tip; an accessory process on the middle two of the terminal four elements on the exopod of leg 1; and a bipectinate, spiniform process on the exopod of leg 4 at the insertion of each of the five outer spines.  相似文献   

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