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1.
Summary

In this paper the different interpretations of the genus Delthyris are discussed, and that given by Schuchert in 1913 is adopted with slight amendment. The species Delthyris elevata, D. crispa, D. elegans (nom. nov. for D. crispa, Hisinger, non Linnæus), and D. tenuilamellata, sp. n., from the British Silurian, are all described and figured.

The distinguishing characters of the genera Uncinulus and Uncinulina are pointed out, and Uncinulina is retained with U. fallaciosa as genotype. Rhynchonella stricklandi and Terebratula lewisi are transferred to the genus Uncinulina. Meristina tumida (Dalman) is shown to be a synonym of Meristina obtusa (Sowerby).

The British Silurian Spirifers can be separated into two groups:—(1) those with longitudinal folds and a transverse ornament of imbricating lamellæ (=Delthyris of Dalman) and (2) those with longitudinal folds bearing fine continuous longitudinal striæ (=Eospirifer of Schuchert).

The species referable to both these genera have as a rule been assigned to the genus Spirifer, from which, however, they differ in internal characters.  相似文献   

2.
ABSTRACT

Noyesaphytis Polaszek & Woolley gen. nov. (type species Noyesaphytis lasallei Polaszek & Woolley sp. n. ) is described from Berenty, Tuléar, Madagascar. The genus differs from its closest relatives primarily in the structure of the female antenna, which has a single, elongate flagellum preceded by four anelli, the largest of which could be interpreted as a single anelliform funicle. This type of antenna is unknown in other Aphytini, but approaches the condition found in many Signiphoridae. Noyesaphytis possesses a character state that was until now thought to be an autapomorphy of Azotidae (sole genus Ablerus), being the groove in front of the propodeal spiracle. A second putative autapomorphy shared by Azotidae and Signiphoridae, and also Noyesaphytis, is the presence of anterior projections on the metasomal sterna. However, in Azotidae and Signiphoridae these are narrow, whereas as they are broader in Noyesaphytis. The form of the wing is consistent with Aphytini, although lacking a linea calva. The presumed male of Noyesaphytis lasallei has an antennal structure completely unknown in Aphelinidae, with a 1-segmented clava preceded by an extremely elongate single funicle, and four anelli. Differences between the female and male are discussed, some of which could indicate that the male might eventually be shown to belong to a different species, although the species are undoubtedly congeneric, despite the striking difference in antennal structure which is common in Aphelinidae. The male genitalia also suggest Aphytini. Based on a phylogenetic analysis of 50 morphological characters, we provisionally place Noyesaphytis in Aphytini pending the results of a forthcoming phylogenomic analysis. The new genus is named for its collector, John Noyes (NHM, London), and the new species is named after the late John La Salle.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:6EE6F35C-32A4-4E91-AE39-5E2C173E58BF  相似文献   

3.
Summary

The Chalk Echinoids of the genera Infulaster and Hagenowia are redescribed. Three published species of Infulaster are regarded as synomyns of the genotype species. Two new species of Hagenowia are described from the English Senonian. While Infulaster is held to be an Echinocorythid of the subfamily Cardiasterinæ, Hagenowia is shown, by certain important structural features, to belong to the curious family Pourtalesiidæ of Loven. The phylogeny of the forms considered is also discussed.  相似文献   

4.
《Journal of Natural History》2012,46(23-24):1491-1514
ABSTRACT

A comprehensive revision of the genus Thalerosphyrus in Thailand is assessed. Four species are recognised: T. flowersi, T. sinuosus, T. vietnamensis and one new species, Thalerosphyrus thailandensis sp. nov., which is described here. A morphological comparison of the described species is provided. A Maximum Likelihood (ML) consensus tree based on 658 bp of the mitochondrial cytochrome oxidase I (COI) gene of five species was performed. Uncorrected p-distances strongly support the identity of these species, originally based on morphology, and show differences of 8.4–29.8% between species and 1.4–6.3% within species.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:850FB31C-2B6A-4AB2-92D5-3413B193F196  相似文献   

5.
Summary

The variability of four characters commonly used in the separation of species of Limnodrilus has been described, and their relative values assessed. The number of setae per bundle is useless as a specific character; the shape of the setae can serve to distinguish only a single species and the length: breadth ratio of the penial sheath is more useful as an additional or confirmatory character. The shape of the penial sheath proved to be the most important character, but even this was not completely reliable, and it is concluded that several characters must be used in the identification of species of Limnodrilus. It is suggested that structures other than the cuticular derivatives should be examined and that a similar study be carried out on North American species.  相似文献   

6.
Summary

In 3 years 13 485 female Tabanidae of 4 Genera and 12 species were caught near cattle of a Dar es Salaam dairy farm. 58·44% of the flies were T. fraternus and 24·5% T. taeniola, which, in the context of possible mechanical disease transmission, were considered to be major species.

T. gratus, T. biguttatus and Haematopota decora showed a proportion of 6·77%, 5·8% and 3·5% respectively.

Another 7 species represented altogether 0·98% of the total catch.

The seasonal occurrence of Tabanidae depended on the pattern of annual climatic changes, with the highest seasonal incidence observed in T. taeniola.  相似文献   

7.
8.
《Journal of Natural History》2012,46(33-34):2123-2131
ABSTRACT

A new whitefly species, Pealius satakshiae Dubey, found infesting Quercus leucotrichophora A. Camus (Fagaceae) in the Chail Wildlife Sanctuary, Himachal Pradesh, India, is described. Puparia of the new species differ from described Pealius species in being larger in size, having a differentiated cephalus, rhachisform abdomen and reduced abdominal segment VII, and lacking the first abdominal setae. Puparial characteristics for the genus Pealius Quaintance and Baker in relation to new species are discussed. Camera lucida drawings, images of habitus and holotype, and scanning electron microscope photomicrographs are provided.

http://www.zoobank.org/lsid:zoobank.org:pub:9712A865-4DD6-457B-84B0-1C7873316DE4  相似文献   

9.
Summary

Detailed examination of the cheliceral flagella of four British species (C. cimicoides, L. nodosus, A. dubius, and P. scorpioides) belonging to the family Chernetidae shows that the number of blades is stabilized by the protonymph. The morphology and pattern of growth of the blades are described, and the significance of the flagellum as a useful taxonomic character at the generic, if not specific level, is discussed.  相似文献   

10.
Summary

Larvae of Alpheus heterochaelis from North Carolina hatch from large eggs as advanced zoeae, usually moult three times, and exhibit almost no linear growth during a short (4 days at 25°c) larval development. Stage I lasts 6 hours at most and is sometimes skipped; III lasts about twice as long as II. Individuals simultaneously exhibiting characteristics of Stage III and the postlarva were occasionally seen. The three zoeal stages and postlarva are described in detail and illustrated. Stages in embryonic and juvenile development and the hatching process are briefly described.

An ‘extended’ pattern of larval development, characteristic of most alpheid species, is described in a general way, and the ‘abbreviated’ development of A. heterochaelis compared to it. At hatching, A. heterochaelis larvae bear rudimentary pereiopods and pleopods; other structures are at the same level of development in both patterns, but subsequent morphogenesis is faster in A. heterochaelis. Larval development of Synalpheus spp., some of which exhibit extreme abbreviation or direct development, is briefly described with reference to the A. heterochaelis pattern.  相似文献   

11.
ABSTRACT

A new species of the genus Setelacher Bou?ek, S. lasallei sp. nov. Gumovsky and van Noort, is described from the Afrotropical region (Central African Republic, Gabon and Uganda). It confirms the presence of the genus in the region. The only described species of the genus, S. fasciatus Bou?ek, is of Australasian and Indo-Malayan distribution, and one undescribed species was previously recorded from South Africa. All images presented here are available on www.waspweb.org

http://www.zoobank.org/urn:lsid:zoobank.org:pub:D6AA0B15-6EA7-4C93-827C-1807E69BD6D2  相似文献   

12.
Summary

A new species of terrestrial isopod, Metatrichonixoides celticus is described and differentiated from other European species of the same genus. M. celticus occurs on the coast of South Wales, U.K. and its supralittoral habitat is outlined.  相似文献   

13.
14.
15.
Summary

Information obtained about the association of various flies with different types of filth in Dacca city, their life histories, food preference of the larvae, and the seasonal changes of their population has been recorded.

The filth of Dacca city has been classified into the following eight categories for the present work. (1) Human excrement, (2) cow dung, (3) manure heaps, (4) garbage and kitchen refuse, (5) decaying fruits and vegetables, (6) carrion, (7) rotten fish and meat, and (8) municipal sewage and other liquid waste.

In total nine fixed areas in different parts of the city were visited regularly to collect adult flies, or their eggs or larvae.

The association of various flies with the above eight types of filth has been discussed.

The duration of the life cycle from oviposition to emergence of the adults was recorded for five species of Psychoda, seven species of Musca, one species of Calliphora, two species of Chrysomyia, two species of Lucilia, and three species of Sarcophaga, during summer and winter.

Food preferences of the larvae of two common species of Musca, two species of Sarcophaga, one species of Lucilia, one species of Calliphora, and two species of Chrysomyia have been recorded.

The trend of the seasonal variation of the various fly populations have been discussed.  相似文献   

16.
《Journal of Natural History》2012,46(100-102):189-197
Abstract

The occurrence in South West Africa, i.e. within the confines of the Republic of South Africa, of the Amphipod genus Ingolfiella Hansen is recorded. The species is subterranean, is larger than any of the previously known species, and is described as I. opisthodorus sp. n. It is compared with I. leleupi Ruffo from the Congo and Northern Rhodesia. The majority of the specimens seem to be females although none has even a trace of oostegites or brood lamellæ. They exhibit a marked dimorphism of the first pair of pleopods, chiefly in specimens exceeding 14 mm. in body length; a juvenile form of this pair occurs in specimens measuring 12 to 14 mm. A few supposed males, among the last specimens to be collected (in June), are smaller than the supposed females but the two pairs of gnathopods are relatively larger and of a different form.  相似文献   

17.
《Journal of Natural History》2012,46(21-22):1351-1368
ABSTRACT

In Mexico, there are currently two known species of Racekiela: R. ryderii and R. montemflumina. Here we describe a new species from high-altitude streams in central and southern Mexico. Racekiela cresciscrystae sp. nov. presents two morphotypes: thick encrusting with raised ridges or lobose outgrowths at the surface and dark green in colour, or lime-green encrustations. The new species as megascleres presents microspined oxeas from 200 to 300 µm long, some centrotylote, or with malformations. Gemmules are spherical with a tri-layered theca, constituted by radially embedded birotules and pseudobirotules. The birotules have longer shaft than the rotule diameter, which is flat, and some slightly umbonate. Pseudobirotules of typical morphology have strongly or somewhat spined shaft. Spines can be straight or hooked. The species also presents other type of pseudobirotules, which are umbonate and with only small warts, instead of spines. DNA sequences from the nuclear ITS1-5.8-ITS2 region were sequenced from the holotype and a paratype of the new species to determine their phylogenetic relationships with other members of the family Spongillidae. Tree topologies (Bayesian Inference and Maximum Likelihood) were consistent in showing Racekiela creciscrystae sp. nov. as a sister clade of R. montemflumina confirming its allocation in a monophyletic genus Racekiela. A comparison with all the Racekiela species described so far is also included. This paper increases the number of species of freshwater sponges in Mexico, and confirmed that Racekiela is a monophyletic genus with morphological characters very well defined.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:3769C54F-23C4-409A-AF02-81F3AA084F7A

http://www.zoobank.org/urn:lsid:zoobank.org:act:A512359D-E428-4D04-B08A-E189E3F6F962  相似文献   

18.
ABSTRACT

We describe two diminutive species of rattlesnakes (genus Crotalus) from small nearshore islands off the coast of Baja California in the western Gulf of California, Mexico. In order to test the hypothesis that some island populations represent cohesive species entities, we applied linear discriminant analysis and uniform validation procedures to multiple classes of intrinsic trait data. By using previously recognised species to establish a threshold for species recognition, we found that assignment of specimens to either new species was as probable as with other established rattlesnake species within the speckled rattlesnake (Crotalus mitchellii) complex. We also found that assignment of specimens from other island populations was not as probable as for the established species, and these populations are referable to C. pyrrhus. The species endemic to Piojo Island is most closely related to other island and mainland populations of C. pyrrhus whereas the species endemic to Cabeza de Caballo Island is apparently most closely related to C. angelensis, a nearby island endemic of large body size. However, patterns from both mitochondrial and nuclear phylogenies, and phenotypic variation, indicate that evolutionary trajectories of both of these species have been influenced by introgression from C. angelensis. We speculate that collective evidence based on contrasting patterns of nuclear and mitochondrial evolution supports a hybrid origin of the species from Cabeza de Caballo Island followed by exceptionally rapid mitochondrial evolution. Consistent with small body size, both species show a reduction in various scale counts relative to other species of the C. mitchellii species complex, suggesting that dwarfism is not simply a plastic response to insular conditions.

http://www.zoobank.org/urn.lsid:zoobank.org:pub:FBC8A11B-04A3-4231-85CA-3972DF5A42FF  相似文献   

19.
Book reviews     
Summary

Five early ontogenic stages of Scomberomorus lineolatus (C. &; V.) ranging in standard length from 18·4 mm to 99·5 mm are described.

Direct comparison of these early stages with those of S. commerson (Lac.) showed differences in the number of gill rakers, the length of preopercular spines and the position of the anal fin in relation to the second dorsal fin. In the case of S. guttatus (Bl. &; Schn.) the gill rakers are of the same number as in S. lineolatus but the preopercular spines decrease in size from above with the upper two subequal in size and none projects beyond the operculum.

In the earlier stages, S. lineolatus could be easily distinguished from S. guttatus by the absence of the bluish green coloration characteristic of S. guttatus. In later stages when the coloration has developed in both the species the only marked difference between the two is in the nature of the bent portion of the lateral line which is wavy in S. lineolatus and straight in S. guttatus.

The number of vertebrae is 46 in S. lineolatus; 42–45 with 43·9 as mean in S. commerson and 47–52 with 49·7 as mean in S. guttatus.  相似文献   

20.
Summary

The morphology of adults and young of Acanthomia tomentosicollis Stål. and A. horrida, Germ. is described. Measurements of head-width and antennal segments of nymphs and adults were made. The heads of adults and nymphs of A. tomentosicollis are wider than those of A. horrida. The comparisons of head and antennal growth showed that the two species developed at about the same rate. Some of the morphological features of these species are remarkably primitive and are probably new features known in the Pentatomamorpha.  相似文献   

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