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1.
The sand boas of the genus Eryx (Daudin, 1803) comprise four species in northe-astern Iran: E. tataricus (Lichtenstein, 1823), E. miliaris (Pallas, 1773), E. elegans (Gray, 1849), and E. jaculus (Linnaeus, 1758). Based on a morphological study of the Eryx species in the area, a high similarity between E. tataricus and E. miliaris on the one side, and E. jaculus and E. elegans on the other side has been well documented, so that they are hardly distinguishable from each other. We analysed sequences of the mitochondrial cytochrome b gene of 29 individuals of morphotypes of this species complex in north-eastern Iran to clarify the phylogenetic relationships. Based on the branch pattern of the phylogenetic trees, the amounts of genetic distances within and between major clades and considering the morphological data, we concluded that the traditional grouping of species within the genus Eryx in north-eastern Iran should be fundamentally revised. We believe that E. elegans is conspecific with E. jaculus, and E. tataricus is conspecific with E. miliaris. Considering the principle of priority, the north-eastern populations of Eryx in Iran should be classified into only two distinct species: E. jaculus and E. miliaris.  相似文献   

2.
Jerboas belonging to the genus Jaculus are widely distributed rodents inhabiting Palearctic desert and semi‐desert areas. Previous studies on the lesser Egyptian jerboa Jaculus jaculus showed the existence of various morphological forms of controversial taxonomic status. They were sometimes related to two different species, J. jaculus and Jaculus deserti, although this has not been recognized in recent taxonomic updates. To clarify the systematic status of J. jaculus in Tunisia, we performed molecular (phylogenetic analyses of cytochrome b sequences), morphological (multivariate analyses of 13 skull measurements) and karyotypic (standard preparations from bone marrow cells) analyses on a number of specimens collected from ten localities. Our analyses revealed two monophyletic, well differentiated clades, with a mean genetic divergence value (K2P = 10.9 ± 0.01%), which is within the range of distances generally observed between rodent species. Morphometric analyses clearly separated populations of the two genetic clades from each other. However, karyotypes of individuals from both clades appeared similar. Individuals from both molecular clades/morphometric groups were found in sympatry in most of the localities sampled. These results, as obtained from a restricted area of the total distribution, suggest that there are two separate species within the currently accepted J. jaculus in Tunisia. Alternative hypotheses such as the occurrence of a strong, ancient phylogeographic structure, or the presence of pseudogenes, are also considered to account for the results obtained. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 99 , 673–686.  相似文献   

3.
Zusammenfassung Die mit Scribtol injizierten Augen der untersuchten Boidae (Python reticulatus, Eryx johnii, Eryx conicus und Corallus enydris cooki) zeigen im Vergleich zu den Augen aller bisher daraufhin geprüften Colubridae (Natrix natrix, Coluber najadugn, Ahaetulla nasuta und der für these Arbeit gesondert hinzugezogenen Elaphe longissima) eine unterschiedliche, möglicherweise stammesgeschichtlich bedingte Struktur ihres Brillenkapillarnetzes. Während bei den Colubridae bevorzugt eine vertikale Orientierung der langgestreckten Maschen ihres Kapillarnetzes gefunden wird, ist für die Boidae durch die Lage der zu- und abführenden Gefäße eine mehr radiäre Struktur bei weniger gestreckten Maschen kennzeichnend.Die Dichte der Maschen des Kapillarnetzes in dem von den Ocularia freien Brillenteil liegt für Python reticulatus bei 11,4, für Eryx johnii bei 9,2, für Eryx conicus bei 6,3, für Corallus enydris cooki bei 1,8 (!) und für Elaphe longissima bei 11,6 Maschen/mm2.Für die untersuchten Arten liegt in dem von den Ocularia freien Brillenteil die Durchschnittszahl der Kapillarmaschen mit einem Quotienten der Koordinatendifferenzwerte (Abszissen- zu Ordinatenwert, Abszisse=Grenze der Supralabialia) 1 und bezogen auf die Gesamtmaschenzahl für Python reticulatus bei 44,1 %, für Eryx johnii bei 36,5%, für Eryx conicus bei 47,1%, für Corallus enydris cooki bei 49,3%, dagegen fur Elaphe longissima bei 20,3%.Die Lage dieser Kapillarmaschen mit einem Quotienten 1 gibt Auskunft darüber, ob ein oder mehrere Sektoren der Brille eine bevorzugte Maschenform aufweisen. Bei dem radiär strukturierten Brillenkapillarnetz von Python reticulatus ist dies im Gegensatz zu dem ähnlich angeordneten von Gekko gecko nicht der Fall.Im proximalen Teil der Aa. chorioideae, d.h. um den Sehnervenaustritt liegt bei Python reticulatus vorwiegend temporal, dorsal und nasal, aber weniger ventral ein relativ großlumiges Gefäßnetz, dessen Maschen verwunden und mehrfach mit der Choriocapillaris verbunden Bind. Fine ähnliche, wenn auch nicht so starke Anastomosenbildung zwischen den Aa. chorioideae und den Aa. ciliares communes nasalis bzw. temporalis wird auch bei Corallus enydris cooki und Elaphe longiwima festgestellt. Die A. ciliaris communis temporalis gibt bei Eryx conicus kurz vor ihrem Übergang in die A. iridis temporalis einen dorsalen und danach einen ventralen, langen diinnen Zweig ab.Die Choriocapillaris von Corallus enydris cooki wird dorsal von fünf bis sechs Abflüssen, ventral von einer V. chorioidea, neben einem an der Sehnervenscheide liegenden Ringgefäß drainiert.
The eyes, especially the spectacles blood capillary system of Python reticulatus Schneider 1801, Eryx johnii Russel 1801, Eryx conicus Schneider 1801 and Corallus enydris cooki Gray 1842 (Boidae)
Summary Study of the eyes of the Boidae (Python reticulatus, Eryx johnii, Eryx conicus and Corallus enydris cooki) following the injection of Scribtol revealed that the structure of the spectacle capillary network was different from that in Elaphe longissima and the previously investigated Colubridae (Natrix natrix, Coluber najadum and Ahaetulla nasuta), probably due to evolution. While in the Colubridae the orientation of the stretched meshes found in the capillary network is normally vertical, in the Boidae the meshes of the network are typically less tightly stretched and the structure is more radiating, because of the position of the influx and efflux vessels.The density of the meshes of the capillary network in the part of the spectacles not covered by ocularia is 11.4 in Python reticulatus, 9.2 in Eryx johnii, 6.3 in Eryx conicus, 1.8 (!) in Corallus endyris cooki, and 11.6 meshes/mm2 in Elaphe longissima.When the quotient of the values for the coordinate difference (abscissa to ordinate value, abscissa=border of the supralabiala) 1 in the species investigated the average number of capillary meshes in the part of the spectacles not covered by ocularia represents in Python reticulatus 44.1% of all the meshes, 36.5% in Eryx johnii, 47.1% in Eryx conicus and 49.3% in Corallus endyris cooki, values significantly higher than the 20.3 % found in Elaphe longissima.The location of the capillary meshes with a quotient 1 provides information as to whether one or more sectors of the spectacles possess a preferred mesh form. With the radiating structure of Python reticulatus this is not the case, however, in contrast to the similar structure found in Gekko gecko.In the proximal part of the Aa. chorioidaea, that is, in the area where the optic nerve leaves the bulbus, there is a relatively wide luminal vessel network in Python reticulatus, this extends slightly in a ventral direction but more in temporal dorsal and nasal directions, and its meshes are twisted and often connected with the choriocapillaris. The vessel network of Corallus enydris cooki and Elaphe longissima was found to be similar, except that not as many connections were observed between the Aa. chorioideae and the Aa. ciliares communes nasalis or temporalis. In Eryx conicus the A. ciliaris communis temporalis has a dorsal branch shortly before it becomes the A. iridis temporalis, and later a long narrow ventral branch. The choriocapillaris of Corallus enydris cooki is drained dorsally by five or six veins, and ventrally by one V. chorioidea and a ring vessel surrounding the sheath of the optic nerve.
  相似文献   

4.
The rediscovery of the Minor Snake-eyed Skink, Ablepharus grayanus, from two different localities in Sistan and Baluchestan and Kerman Provinces, southeastern Iran is reported. A total of 24 specimens was examined based on morphometrics, colour pattern and pholidotic characters. One-way analyses of variance (ANOVA) based on morphometric measurements revealed significant differences in terms of the snoutvent length (SVL) and fore- and hind limb distances (GA) between eastern and western populations of Ablepharus pannonicus. The most distinguishing characters of Ablepharus grayanus are morphological features, especially ear opening status and scales around the midbody (18-20 versus 20-22). Based on morphological grounds, Ablepharus grayanus is clearly distinguished from A. pannonicus occurring in the eastern and western regions of the Iranian Plateau.  相似文献   

5.
The meadow spittlebugs Philaenus spumarius and P. tesselatus are closely related taxa with uncertain taxonomic position in the light of previous morphological, ecological, cytological and molecular research. Despite morphological homogeneity of P. spumarius (with the exception of high colour and pattern polymorphism) across its wide Holarctic range, it is possible that additional taxa (species or subspecies) exist. Philaenus spumarius is a potentially important pest in parts of its range where it was introduced. We used DNA markers to describe the genetic diversity of P. spumarius and P. tesselatus and to verify the taxonomic status of P. tesselatus and remote populations of the former species. The mitochondrial (cytochrome B) data showed that there are two main groups encompassing a northeastern (Asia and north‐central Europe) and a southwestern (Mediterranean area and western Europe, including North American specimens) clade. According to the elongation factor‐1α gene, there are three main clades: northeastern (Eurasiatic clade, E1), southeastern (east Mediterranean – Caucasus clade, E2) and southwestern (Iberian clade, E3). These two or three mitochondrial and nuclear clades could be considered as separate taxonomic units. On the other hand, all studied individuals of both species possessed the same internal transcribed spacer 2 haplotype. American specimens most probably originated from some western European populations. All studied specimens of P. tesselatus belong to the southwestern clade and western Mediterranean cluster. Therefore, together with cytological data, its species status is doubtful. To definitively solve the taxonomic status of P. tesselatus and populations of P. spumarius, further research using more samples and more genetic markers are needed.  相似文献   

6.
This study is focused on the genus Euphorbia L. in a part of northeast Iran, viz. the three Khorassan provinces. Since there are many taxa of Euphorbia in Iran which are used in different industries and have significant effects on human and non‐human life it is important to revise their taxonomy. With about 90 species, following Turkey with 91 species, Iran is the second richest country for Euphorbia in Asia. Of these, 30 species are distributed in the Khorassan provinces. This is the first comprehensive work on the genus in this region. According to ‘Flora Iranica’, there are 17 species of Euphorbia in northeast Iran, while according to our results, there are 30 species of Euphorbia in the Khorassan provinces alone. In addition to various new taxonomic and biogeographic results, a new species, viz. E. chamanbidensis, is described. Euphorbia chamanbidensis is closely related to E. aucheri, but seed micro‐morphological characters differentiate them. Two identification keys to the Euphorbia species of the studied area are provided, one based on macro‐morphological characters and another based on seed micro‐morphological characters. Phytogeographic analysis and distribution maps for all species are also presented.  相似文献   

7.
8.
Twenty-three morphological features of 140 specimens of Ophisops elegans were analysed in order to identify sexual dimorphism in west and northwestern populations of Iran. Sexual dimorphism is significant (P<0.05) in nearly all metric features except for trunk length (TL) and length of widest part of belly (LWB), and in only two meristic characters, the number of dorsal scales around mid-body (DSN) and the number of femoral pores (FPN). Males have a relatively longer snout-vent length (SVL) than females and males have generally relatively larger heads compared to females.  相似文献   

9.
国家Ⅰ级重点保护极危植物藤枣研究进展   总被引:1,自引:0,他引:1  
国家Ⅰ级重点保护植物藤枣[Eleutharrhena macrocarpa(Diels)Forman]属防己科单种属植物,主要分布于云南南部地区。藤枣因其形态特征和分布式样在防己科植物中较为独特,具有重要的植物系统学和区系地理学研究价值。据相关文献记载,目前发现和记录的藤枣自然种群数量小于60株,种群处于极危状态,面临灭绝风险。国内外与藤枣相关的研究资料也相对匮乏。为及时拯救和关注这一濒危物种,该文在前贤研究的基础上,总结报道了藤枣的分类学简史、科学研究价值、自然种群数量、濒危状况、生物多样性保护地位、区系分布、模式标本认定等方面的最新研究进展,提出了近期的研究目标。期望能对藤枣的准确鉴定、精准调查和进一步深入研究提供基础信息和理论参考。  相似文献   

10.
Aim The ‘taxonomic impediment’ has led to a growing trend in ecology and conservation biology to use operational surrogates for species within the context of a particular research project. Because such ‘parataxonomic’ classifications are typically spatially limited in scope, we examined the influence of increasing spatial scale on the congruence of two such approaches with a more traditional taxonomic classification. Location Sturt National Park, north‐western New South Wales, Australia. Methods Specimens of two ant genera, Camponotus and Rhytidoponera, were classified by three independent methods. The ‘parataxonomic’ classification assigned specimens to morphospecies without specialist taxonomic expertise; the ‘taxonomic’ classification assigned specimens to either described species or, where this was not possible, to operational taxonomic units (OTUs) using specialist taxonomic expertise; the ‘phenetic’ classification assigned specimens to putative species using a K‐means partitioning algorithm on basic morphometric data. Specimens of each genus were pooled into ‘assemblages’, which were defined at multiple spatial scales using a nested sampling design. Congruence in the interspecimen relationships of the different classifications was tested for each assemblage using pair‐wise Mantel correlations. Results Classification congruence tended to decrease with increasing spatial scale. There were, however, clear differences between the genera. Parataxonomic–taxonomic congruence was consistently greater for Camponotus, while phenetic–taxonomic congruence showed the opposite pattern. Conclusions Observed patterns in classification congruence are attributed to two principal causes: (i) within‐species morphological variation, including ecotypic variation in Rhytidoponera and caste polymorphism in Camponotus; and (ii) a limit to the morphological similarity of potentially competing species at small spatial scales. Regardless of cause, the decline in agreement as the spatial scale of observation is increased has important implications for the measurement of biodiversity, particularly when comparing samples over regional, continental, and global scales.  相似文献   

11.
12.
Fleas are important vectors of diseases such as murine typhus, tularaemia, hymenolepiasis and plague. The presence of active foci and history of human‐ and flea‐transmitted plague in northwest Iran prompted the present group to collect and identify fleas from human and livestock dwellings across West Azerbaijan Province. Adult fleas were collected and identified using routine taxonomic keys. Species designation was confirmed by sequencing the cytochrome oxidase subunit I (COI). Of the collected specimens (n = 989), 104 were collected off‐host (30 from human dwellings and 74 in light traps) and the rest were found on hosts (107 on animals and 778 by human bait). Of these fleas, 394 (40%) were male and 595 (60%) were female. The collected specimens belonged to the species Ctenocephalides canis, Ctenocephalides felis, Ctenocephalides orientis and Pulex irritans (all: Siphonaptera: Pulicidae). The amplified COI fragment, in addition to confirming the morphological identification of species, showed good efficacy in separating the different species in the phylogenetic analysis. In addition to the identification of fleas from human and livestock dwellings using morphological and molecular characteristics, the current paper represents the first report of the presence of C. orientis in northwest Iran. This finding suggests that changing climate conditions may have expanded the distribution of this species.  相似文献   

13.
Two clades of the lesser Egyptian jerboa Jaculus jaculus sensu lato were recently described in North Africa and considered as cryptic species. Members of both clades are also found in Israel, where they can be easily identified according to fur and tail colouration and morphology of the male external genitalia, but cannot be separated confidently using skull characters. Examination of type specimens demonstrated that the correct names for the two species are Jaculus jaculus (Linnaeus 1758) and Jaculus hirtipes (Lichtenstein, 1823). Comparisons of geographic and habitat differences of the two species revealed a high niche divergence between them, slightly higher in the sympatric North African populations than in the parapatric populations of Israel and Sinai. A low niche divergence was detected between North African and Middle Eastern populations of J. jaculus, and a low niche convergence between North African and Middle Eastern populations of J. hirtipes. The levels of niche differentiation coincide with those of genetic differences.  相似文献   

14.
15.
Bláha, M., Hulák, M., Slouková, J. & Tě?itel, J. (2010). Molecular and morphological patterns across Acanthocyclops vernalis‐robustus species complex (Copepoda, Cyclopoida).—Zoologica Scripta, 39, 259–268. Morphological traits within Acanthocyclops (Kiefer, 1927) are highly variable, and morphology is too constrained to give complete information of phylogenetic relationships. This study combined morphological and molecular techniques to investigate the taxonomic and phylogenetic relationships of three species of Acanthocyclops (Acanthocyclops trajani, Acanthocyclops einslei and Acanthocyclops vernalis) inhabiting continental Europe. Morphological indices subjected to principal component analysis (PCA) separated sample populations into three distinct clusters corresponding with the taxonomic status of the species analysed. In addition, the taxonomy status of A. trajani and A. einslei was in agreement with molecular data; however, the intraspecific variation in sequences of 12S rRNA was lower in contrast to specimens morphologically determined as A. vernalis, which were divided into two deeply divergent clades, based on mtDNA sequence divergences. Moreover, high sequence divergence (26%) between these clades indicated the existence of another species that may not be a sister taxon of A. vernalis s.s. Results point to the need for further taxonomic work on Acanthocyclops.  相似文献   

16.
We compared the morphological characters of populations of the Caucasian Pit Viper, Gloydius halys caucasicus, from different regions of the Alborz mountain range. For this purpose, we studied 7 metric and 21 meristic characters in 12 specimens from the western Alborz, 44 specimens from the eastern Alborz and nine specimens from the central Alborz Mountains. The results of the statistical analyses by npMANOVA, ANOVA and Kruskal Wallis tests showed significant differences between all three populations, while the western Alborz and the eastern Alborz populations are more distinct from each other. The important characters showing differences between them are: Subcaudals, dorsal scales in anterior part, dorsal scales in posterior part, supralabial scales, scales between gulars, gulars, ventrals, ratio of snout length over snout width, and ratio of snout length over head length.  相似文献   

17.
Aphanius Nardo, 1827 (Actinopterygii, Cyprinodontidae) is a widely distributed genus in the Mediterranean and Persian Gulf area and includes several endangered species. The otolith morphology in Aphanius is known to represent a valuable tool for the taxonomy, and is also indicative for the genetic diversity of a particular population. The present study focuses on the otoliths of the endangered A. ginaonis (Holly, 1929), which is endemic to the Geno hot spring in southern Iran. The taxonomic status of A. ginaonis has repeatedly been questioned, and some scholars have argued that it merely represents a morphological variation of the widespread A. dispar. We present a comparison of the otolith morphology of A. ginaonis (52 specimens) with that of A. dispar (Rüppell, 1828) from the Mehran River Basin (southern Iran) (17 specimens) and an A. dispar population from the Persian Gulf coast of the United Arab Emirates (32 specimens). Our data obtained from SEM pictures, otolith morphometry and statistical analyses suggest that A. ginaonis represents a valid species. In A. ginaonis individuals with a standard length exceeding 23 mm, the otolith variables length–height and rostrum length represent useful complementary diagnostic characters discriminating this species from other Aphanius species. Besides ontogenetic variation, we found extremely high otolith form variability in A. ginaonis, including some otoliths with a morphology distinctly deviating from the basic morphology type. We hypothesize that these variations may be a result of the artificial introduction of A. dispar into the Geno hot spring during the last years and subsequent hybridisation.  相似文献   

18.
The desert biota is exposed to extreme and variable conditions that shape its evolution and diversification processes. In this respect, the Jaculus jerboas have gained the attention of researchers as a result of their broad Saharan–Arabian distribution and their high and unexplained, morphological, anatomical, and molecular variation. In the present study, mitochondrial and nuclear genealogies where used to confirm monophyly of two cryptic species: Jaculus jaculus and Jaculus deserti. The reconstructed demography showed that the evolutionary histories of the species are markedly different and that the expansion into North‐West Africa by J. deserti was more recent than that of J. jaculus. The weak ecological separation between species and the signs of recent population growth and expansion of J. deserti suggest that its sympatric occurrence with J. jaculus is recent and that these species evolved in isolated populations, after diverging around the Pliocene–Pleistocene boundary. The importance of climate changes on the Sahara Desert biota is discussed in the context of genetic diversification. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 105 , 435–445.  相似文献   

19.
Fifteen cranial measurements were taken from wild caught specimens ofAlouatta seniculus seniculus, A. s. stramineus andA. s. macconnelli. A morphological analysis showed sex dimorphism in these three groups. A multivariate analysis discriminated among these taxa; males being more clearly discriminated than females. Our data showed that these taxa can be separated on the basis of quantitative cranial traits, biogeographic distribution, karyological differences, and biochemical characters. We therefore propose a new taxonomic arrangement, changing their taxonomic status to the species level (Alouatta seniculus, A. macconnelli, andA. stramineus).  相似文献   

20.
Grass shrimps Palaemon mundusnovus, P. pugio and P. vulgaris sympatrically inhabit in the Laguna Madre, Mexico. They exhibit very close morphological similarity and overlap in their diagnostic characteristics, which has hindered certainty in their identification and has raised doubt regarding their taxonomic validity. In this work, we analyse intra‐ and interspecific morphometric and meristic variability through a multivariate analysis, and we determine the molecular variation using mitochondrial sequences of the 12S, 16S and COX1 genes to confirm the validity of the three taxa as having distinct lineages or to recognize a smaller number of species with phenotypic plasticity. Our results corroborate the taxonomic validity of the three species; however, there is intraspecific plasticity, interspecific overlap of characteristics and greater morphological and molecular similarity between the species P. mundusnovus and P. pugio, whereas P. vulgaris was better delimited. These species form a monophyletic group but the phylogenetic relationship obtained is discussed. Telson length was the primary variable in the principal components analysis, whereas the length of the propodus of the second pereiopod was the best discriminant. The range of variation reported in the characteristics linked to the rostrum is extended, and its influence on the separation of these species is recognized. The joint application of multivariate analysis from morphological variables and molecular tools is recommended to clarify the taxonomic status of species featuring close morphological similarity and sympatric distribution.  相似文献   

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