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1.
Soricid remains collected from Bed I of Olduvai Gorge are described. The great majority of the specimens are mandibles. A survey of the mandibles of living African species revealed many differences in characters of the lower teeth and jaw that can be used for identification. On the basis of these characters, nine species are distinguished in the Olduvai collection, of which six are well enough preserved to permit a discussion of their relationships to living species. Three new species and one new subspecies are described. All the Olduvai shrews differ in some respects from their nearest living relatives; three species are close to species from Makapansgat, Swartkrans and Sterkfontein, RSA, though there appear to be slight differences. A change in the soricid fauna takes place within Bed I, interpreted as due to increasing aridity.  相似文献   

2.
Previous systematic treatments of the neotropical palm genus Hyospathe have recognized from two to 18 species. An explicit, quantitative, repeatable sequence of operations for delimiting and testing groups of specimens and applying species concepts is carried out. Multivariate statistical analysis of morphological data is used to delimit and test groups of specimens. Cluster analysis is used to distinguish between characters and traits. Analysis of qualitative and quantitative characters reveals six groups of specimens, and the Phylogenetic Species Concept is applied to these groups. Two species, H. peruviana Henderson and H. frontinensis Henderson, are described as new. One of the specimen groups is large and widespread, and six geographically separate subgroups can be recognized within it. These subgroups can be distinguished by one or more significantly different quantitative characters. A Phylogenetic Subspecies Concept is applied to these subgroups. Three subspecies, H. elegans subsp. costaricensis Henderson, H. elegans subsp. sanblasensis Henderson, and H. elegans subsp. tacarcunensis Henderson are described as new, and two new combinations are made: H. elegans subsp. sodiroi (Dammer ex Burret) Henderson and H. elegans subsp. concinna (H. E. Moore) Henderson. One subspecies occurring in the Amazon region is complex morphologically and is not resolved by the methods used here.  相似文献   

3.
The generic concept of Gelasine Herb. (Iridaceae) is reviewed, and the characters discussed in connection with Sphenostigma Bak., a synonym of Gelasine. The reduction of Sphenostigma is further justified on account of overlapping features. A new species from Uruguay, G. uruguaiensis Rav. sp. nov., is described and illustrated. This is shown to include two subspecies: ssp. uruguaiensis , and ssp. orientalis ssp. nov. The chromosome number of the latter is 2n = 14.  相似文献   

4.
The type material of the Cretaceous ornithopod Iguanodon orientalis Rozhdestvensky, 1952 is redescribed. The characters which were ori0ginally used to establish a new species are shown to be either incorrect or indistinguishable from Iguanodon bernissartensis Boulenger, 1881. Additional material, previously unrecognized, further confirms the similarity of I. orientalis to I. bernissartensis. It is proposed that I. orientalis should be relegated in synonymy as a junior subjective synonym of I. bernissartensis Boulenger, 1881. The identification of the Barremian species I. bernissartensis in Asia indicates an unusually wide geographic spread for this species, and provides a potential biostratigraphic indicator for beds in Mongolia which had been previously dated variously between the Cenomanian and Maastrichtian stages.  相似文献   

5.
A cytological survey ofLeucanthemum species in North Africa has shown that they are all diploid with a somatic chromosome number of 2n = 18. New counts are reported for 8 species and 1 subspecies. 11 taxa were used in a crossing programme and the results show a good agreement between phenetic distance based on morphological characters and genetic differentiation as expressed in the ability of the species to hybridize. A strong barrier to gene exchange exists between European and North African species. Bagging experiments showed that the North African species comprise a self-incompatible group of cytogenetically related species.  相似文献   

6.
The genus Cidaria Treitschke is revised. Eight species of the genus which occur widely in the Palaearctic and northern India, are recognized, of which one, Cidaria luteata sp. nov. , is described as new while two subspecies of C. fulvata (Forster) are elevated to species, C. nugata Felder stat. rev., and C. distinctata Staudinger stat. nov. C. ochripennis Prout is proposed as a junior synonym of C. ochreata Staudinger. C. deletaria Hampson is excluded from the genus. All species of Cidaria and their genitalia are described and illustrated. The cladistic analysis of these eight species of Cidaria is carried out using two data matrices, the first comprising morphological characters alone and the second morphological and distributional characters. The most parsimonious cladogram of Cidaria is selected, and its monophyly defined. The character analysis shows that some distribution characters contribute to resolving the in group node. The choice of multiple trees is discussed.  相似文献   

7.
The genus Monobellu Cassagnau, 1979 (Collembola) is redefined. Four new species and one new subspecies are described from Pyrenees and Cevennes (France) on the basis of labrum morphology, tubercle arrangement on tergites and chaetotaxy of somites: Monobellu culvu sp. n., Monobellu eduphica sp. n., Monobellu grussei minor ssp. n., Monobellu juu sp. n., and Monobellu rousseti sp. n. The subspecies Monobellu grussei dubiu Deharveng, 1986 is reassigned to specific level. A key to the 14 species and subspecies of Monobellu is given. Except M. g. minor ssp. n. which is present in the Pyrenees and the Massif Central and the widespread M. g. grussei (Denis, 1923), all Monobellu species and subspecies are narrow endemics of the Pyrenean range; their distribution is mapped in details. A phylogenetic analysis is performed, taking into account the high level of polymorphism of some characters and the incomplete genetic isolation between certain subspecies, indicated in the field by the presence of narrow hybrid zones. Though obtained under different assumptions and constraints, the most parsimonious cladograms exhibit only slight differences, and the proposed phyletic reconstruction can be considered as robust. It adequately reflects the known distribution of the species in the Pyrenees, it confirms the monophyly of the species M. grussei and supports, in agreement with field distribution data, the idea that reticulate evolution might have occurred in this taxon. © The Norwegian Academy of Science and Letters  相似文献   

8.
Although the integration of DNA information in taxonomy has been invaluable, logistical problems relating to sampling can seriously limit its applicability. Here we describe the analysis of a morphologically cryptic species complex, in which we maximize the information present by using both a DNA phylogeny and a multivariate morphometric approach. The green pitviper Trimeresurus stejnegeri s.l. is widespread in Asia, with a number of described subspecies (some of which are considered full species by some workers) and two new species that have recently been described from Thailand. The phylogeny indicates three clades, which can also be discerned in the principal component analyses of morphological variation. Combining molecular and morphological information permits evaluation of the taxonomic position of populations not represented in the phylogeny − in particular, the subspecies T. s. chenbihui and T. s. yunnanensis . We discuss nomenclatural issues raised by this analysis, although these cannot be fully resolved until the holotypes of these subspecies can be examined. Finally, we apply a molecular clock calibrated in New World pitvipers, and discuss some of the palaeoclimatic changes that might have impacted upon diversification in this group.  © 2004 The Linnean Society of London, Biological Journal of the Linnean Society, 2004, 82 , 219–235.  相似文献   

9.
We studied external morphology and molecular genetics of two forms of the oriental fire-bellied toad, described as separate subspecies Bombina orientalis silvatica Korotkov, 1972, and Bombina orientalis practicola Korotkov, 1972. We have found significant differences between them in body size, coloration and some morphometric parameters but not in genetics. Taking into account their geographical separation, one can consider them as forest and meadow ecological morphs but not different taxa. Therefore, the names Bombina orientalis practicola Korotkov, 1972, and B. orientalis silvatica Korotkov, 1972, should be considered as junior synonyms of the name Bombina orientalis (Boulenger, 1980). We suppose that these morphs have been isolated from each other recently, and their morphological differences at genetic similarity are related to high plasticity of the species, when ecologically determined morphological differentiation precedes genetic differentiation.  相似文献   

10.
The larvae of Leptus Latreille, 1796 (Acarina: Erythraeidae) of Europe and North America are comprehensively revised. Of those described since 1900 a total of 34 species is considered recognizable and capable of being keyed; no species described before 1900 is considered recognizable. The nominal type of the genus, Acarus phalangii de Geer, 1778 is rejected as an illegitimate name. Eighteen European and 17 North American species are described and keyed, of which 17 are new to science. One new subspecies from North America, of a species previously known from Europe, is described and keyed. Standard metric data are given for each species or subspecies from available specimens (except two North American species, L. ariel Southcott and L. clarki Southcott, recently described elsewhere; for these last-named two additional metric data are given). Larvae have been recorded from April to September, with the greatest number found being for July and August.
Protonymphs are described for two North American species ( L. ghiradellae sp. nov. and L. welbourni sp. nov. ), and deutonymphs for two North American species ( L. calix sp. nov. and L. ghiradellae ). Keys are given to separate the reared protonymphs, and three described deutonymphs (the two preceding and the European L. galerucae Feider). Data on the duration of the protonymphal instar suggest that in North America and Europe there are two modes: one lasting 3–4 weeks, the other 5–7 months. Developmental abnormalities are recorded systematically.  相似文献   

11.
Careful investigations of live coloration and other characters in the eublepharid gecko Goniurosaurus kuroiwae orientalis from Tonakijima Island, the type locality of the subspecies in the Central Ryukyus, Japan, revealed its slight but consistent external differences from the consubspecific Tokashikijima population, whose phylogenetically divergent status against the former had been strongly suggested in a previous molecular study. A new subspecies, Goniurosaurus kuroiwae sengokui subsp. nov., is thus described for the Tokashikijima population. In life, Goniurosaurus k. sengokui subsp. nov. can be discriminated from G. k. orientalis in showing tint of reddish or pinkish, instead of yellowish, coloration in dorsal body pattern, and also usually darker and more or less reddish, instead of yellowish or grayish, iris in both adults and juveniles. Recalculation of sequence data at hand with relevant Gen Bank data confirmed substantial sequence divergences of G. k. sengokui from all other congeneric taxa of the Ryukyus described so far.  相似文献   

12.
This paper comprises a complete revision of the Afrotropical species of the genus Amerila ( Rhodogastria auct.), based on adult morphology. Examination of type material for most described taxa has resulted in numerous taxonomic changes. From a total of forty-seven previously described African taxa, thirty-five species including five newly described species and two new subspecies are recognized. For ten taxa, lectotypes have been selected, and for one species a neotype had to be designated. For each species, in addition to synonymy, a brief diagnosis based on external characters and genitalia is given, and the known distribution summarized. All species are illustrated by photographs and illustrations of male genitalia (except A.rufifemur , the male of which is unknown), and a key for determination of males by external characters is provided.  相似文献   

13.
The taxonomy of Prunus subgenus Prunus is notoriously problematic and reliable discriminating characters for species and subspecies identification are missing. Principal Component Analysis (PCA) was performed on different morphological data sets and useful diagnostic characters for Prunus spinosa and P. domestica ssp. insititia were found. Many traditionally used morphological characters were found unreliable. The hypothesis of widespread hybridization between Prunus spinosa and P. domestica ssp. insititia in Denmark were examined using PCA and HYWIN. It was found that hybrids between the two taxa are rare in Denmark.  相似文献   

14.
Detailed examination of the periotic bones of ten species of phalangerid marsupials revealed the existence of three distinctive classes of periotic morphology, termed ailuropine, trichosurin and phalangerin. Cladistic analysis of fifteen characters of the periotic suggested the ailuropine periotic to be the most plesiomorphic in morphology, with the trichosurin and phalangerin periotics representing a more derived clade. This character distribution would support recent taxonomic schemes, in which the cuscuses are seen as a paraphyletic grouping: the greater and lesser Sulawesi cuscuses ( Ailurops ursinus and Strigocuscus celebensis ) exhibiting respectively ailuropine and trichosurin periotics, with all other cuscuses possessing phalangerin periotics. However, it does not support the assertions of some authors that the Moluccan cuscuses ( Phalanger ornatus and P. rothschildi ) and the ground cuscus ( P. gymotis ) are trichosurins.  相似文献   

15.
Eighteen graded non-metric characters and 30 measurements of the mandible and lower dentition were used to investigate the grouping of African species of the genera Crocidura, Suncus and Sylvisorex. Seventy-seven taxa (species, subspecies and synonyms), including four European species, were represented by one to nine mandibles (147 mandibles in all), and the means of four Pleistocene African species were also included. The metric data were subjected to principal component and canonical variate analyses, and the non-metric data to principal component analysis. Grouping was detected by comparing the results of the three analyses. Six groups are recognized within the genus Crocidura , typified by C. fumosa, C. turba, C. russula, C. fuscomurina, C. hirta and C. flavescens. Sylvisorex is divisible into two groups, typified by S. lunaris and S. granti. The African species of Suncus (but not the introduced species, S. murinus ) form a single group, which is linked to the Sylvisorex granti group. Suncus is closely related to, or convergent with, the Crocidura fuscomurina group. The first non-metric principal component, the second metric principal component and the second canonical variate are significantly correlated. It is considered that these together represent a general trend of evolutionary advance. Phylogenetic relations are discussed in the light of this; Crocidura may be diphylefic.  相似文献   

16.
L. A. Kutikova 《Hydrobiologia》1980,73(1-3):215-220
An attempt is undertaken to determine criteria and limits of taxonomic rank in the genus Notholca proceeding from the standpoint of level-values of the characters evolution. Level-values of characters were established using Vavilov's principle of homologic series of hereditary variability. As a result of taxonomic revision such terms as group of species, species and subspecies are recommended. Analysis of the scheme of relations between representatives of the genus and data on their ranges gives a clue to relations between phylogeny and geographic distribution of the group over the vast territory of the Asian continent which may have been its centre of speciation.  相似文献   

17.
A new species of Heliconius and a new geographical race of Heliconius melpomene are described from the vicinity of Mocoa, Dpto. Putumayo, Colombia, based on molecular and morphological characters. The new species, H. tristero , is a close relative of H. cydno , a geographically differentiated species which lacks red coloration and engages in Müllerian mimicry with other blue and yellow Heliconius species in Central and northwestern South America. H. tristero has switched mimetic associations, instead mimicking the local, sympatric forms of two widespread mimetic species, H. erato and H. melpomene. This discovery provides evidence that the splinter species H. heurippa, H. tristero and H. timareta represent phenotypically divergent members of the H. cydno group that are endemic to successive river valleys on the eastern slope of the northern Andean Cordillera. The nominal taxon Heliconius amaryllis bellula Stichel, currently misapplied to both H. tristero and H. melpomene populations from the Mocoa region of Colombia, is considered here to represent a hybrid between H. heurippa and H. tristero. The Mocoa melpomene race is formally named Heliconius melpomene mocoa , new subspecies.  相似文献   

18.
19.
在本文中描述了乌头属和翠雀属各一新种和一新亚种,唐松草属一新种,侧金盏花属一新亚种,以及毛茛属五新种,首次报道了圆叶唐松草在中国西藏南部的分布,在对叶、雄蕊和心皮的形态特征进行了分析之后认为,这种植物与特产云南的糙叶唐松草有一定亲缘关系。  相似文献   

20.
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