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1.
We review the distribution, morphology and taxonomic status of Eryx elegans, E. jaculus, E. miliaris, E. tataricus and E. johnii in Iran and examine four metric and 10 meristic characters of 94 specimens from different parts of the country. There are significant morphological differences between Eryx tataricus, E. jaculus and E. elegans, mainly in snout vent length, tail length, and number of ventrals, subcaudals and dorsal scales. Eryx jayakari and E. johnii can easily be distinguished based on their morphological traits and limited distribution in Iran. The occurrence of E. miliaris in Iran was not confirmed. The Iranian populations of Eryx jaculus are assigned to the subspecies E. j. turcicus. E. jaculus specimens from southwestern Iran had higher ventral scales than other populations, so evaluating their taxonomic status needs genetic studies in the future. A distribution map and a revised key to the genus Eryx in Iran are presented.  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.
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   

4.
Species and varieties in the genus Eudorina Ehrenberg (Volvocaceae, Chlorophyta) were evaluated on the basis of phylogenetic analyses of the large subunit ofribulose-1,5-bis-phosphate carboxylase/oxygenase (rbcL) gene sequences from 14 strains of four Eudorina species, as well as from nine species of Pleodorina and Volvox. The sequence data suggested that 10 of the 14 Eudorina strains form three separate and robust monophyletic groups within the nonmonophyletic genus Eudorina. The first group comprises all three strains of E. unicocca G. M. Smith; the second group consists of one of the E. elegans Ehrenberg var. elegans strains, the E. cylindrica Korshikov strain, and both E. illinoisensis (Kofoid) Pascher strains; and the third group consists of two monoecious varieties of E. elegans [two strains of E. elegans var. synoica Goldstein and one strain of E. elegans var. carteri (G. M. Smith) Goldstein]. In addition, E. illinoisensis represents a poly- or paraphyletic species within the second group. The remaining four strains, all of which are assigned to E. elegans var. elegans, are nonmonophyletic. Although their position in the phylogenetic trees is more or less ambiguous, they are ancestral to other taxa in the large anisogamous/oogamous monophyletic group including Eudorina, Pleodorina, and Volvox (except for sect. Volvox). Thus, the four Eudorina groups resolved in the present molecular phylogeny do not correspond with the species concepts of Eudorina based on vegetative morphology, but they do reflect the results of the previous intercrossing experiments and modes of monoecious and dioecious sexual reproduction.  相似文献   

5.
6.
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   

7.
We studied the structural and cellular organisation of the oviduct of Erythrolamprus miliaris including its morphological variation during the reproductive cycle using light microscopy, scanning electron microscopy and transmission electron microscopy. Four anatomically distinct regions compose the oviduct of E. miliaris including the anterior and posterior infundibulum, glandular uterus, non-glandular uterus and pouch. The cells of the oviductal epithelium secrete material by apocrine and merocrine processes, which vary between the anatomical regions and according to each phase of the reproductive cycle. The infundibular epithelium secretes electron dense vacuoles, which suggests the production of lipids, whereas the epithelial secretion of the glandular uterus, non-glandular uterus and pouch creates lucent and slightly electron dense vacuoles, indicating the production of glycoproteins. The timing of mating, vitellogenesis and sperm storage directly influences the morphofunctional alterations in the oviducts of E. miliaris. Sperm storage occurs only in the infundibular receptacles with increased production of the neutral carbohydrates in the presence of male gametes. Sperm storage happens in vitellogenic, non-vitellogenic and pregnant females of E. miliaris. Thus, females may be able to produce multiple clutches at different seasons of the year regardless of mating during autumn.  相似文献   

8.
Jaculus jaculus (Lesser Egyptian jerboa) and Paraechinus aethiopicus (Desert hedgehog) are small mammals which thrive in desert conditions and are found, among others, in the Arabian Peninsula. Jaculus jaculus is omnivorous while P. aethiopicus is described as being insectivorous. The study aims to describe the gastrointestinal tract (GIT) morphology of these animals which differ in diet and phylogeny. The GITs of J. jaculus (n = 8) and P. aethiopicus (n = 7) were weighed, photographed, and the length, basal surface areas, and luminal surface areas of each of the anatomically distinct gastrointestinal segments were determined. The internal aspects of each area were examined and photographed while representative histological sections of each area were processed to wax and stained using haematoxylin and eosin. Both species had a simple unilocular stomach which was confirmed as wholly glandular on histology sections. Paraechinus aethiopicus had a relatively simple GIT which lacked a caecum. The caecum of J. jaculus was elongated, terminating in a narrow cecal appendix which contained lymphoid tissue on histological examination. The internal aspect of the proximal colon of J. jaculus revealed distinct V‐shaped folds. Stomach content analysis of J. jaculus revealed mostly plant and seed material and some insects, whereas P. aethiopicus samples showed plant material in addition to insects, indicating omnivorous feeding tendencies in areas where insects may be scarce. J. Morphol. 277:671–679, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   

9.
The ultrastructure of the mature spermatozoon of the type genus of the Plagiorchiidae Plagiorchis elegans (Rudolphi, 1802), a parasite of the Golden hamster, Mesocricetus auratus is described. This study is the first ultrastructural study of the spermatozoon of a Plagiorchis, the second of a plagiorchiid species and only the third in the Plagiorchioidea. Previously data on spermatozoon ultrastructure existed only for the plagiorchiid Enodiotrema reductum and the omphalometrid Rubenstrema exasperatum. The mature spermatozoon of P. elegans exhibited the general pattern described in most digenean species, namely two axonemes of the 9 + “1” Trepaxonemata pattern, nucleus, mitochondria, external ornamentation of the plasma membrane, spine‐like bodies, and glycogen granules. However, the rather typical expansion of the plasma membrane is not found in P. elegans. Another peculiarity of the spermatozoon of P. elegans is the presence of a structure called thin cytoplasm termination. Spermatozoon ultrastructure of P. elegans is compared with that of E. reductum and R. exasperatum. Spermatozoon of P. elegans conforms to the general pattern described in E. reductum. Thus, this study further expands our knowledge on the spermatozoon ultrastructure among the members of the Plagiorchioidea, one of the most phylogenetically derived groups of the digenea. J. Morphol. 274:965–972, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   

10.
The occurrence of Aphelinus paramali (Zehavi & Rosen) (Hym., Aphelinidae) was evidenced from North east Iran, in association with Aphis pomi (de Geer). This species is reported from Iran for the first time, and A. pomi is introduced as a new host for this parasitoid. Detailed morphological characters were studied with scanning electron microscopy (SEM) photographs. Also, sequences of ribosomal internal transcribed spacer 2 (ITS2) and cytochrome oxidase subunit I (COI) genes were used for determining species boundaries and comparing with other Aphelinus species. Different results were obtained in phylogenetic analysis of these two regions. Analysis of COI gene supported the closer relationship of this species with Aphelinus abdominalis. This is the first data about comprehensive characterization of a parasitic wasp using morphological characters, SEM and two‐locus information from Iran.  相似文献   

11.
A taxonomic study of two brown algal species, Elachista nigra Takamatsu and Elachista orbicularis (Ohta) Skinner (Elachistaceae), was performed on the basis of morphological observations of field‐collected and laboratory cultured specimens from Japan (including their type localities) and molecular phylogenetic analyses. The two species had been distinguished by developmental patterns of paraphysis‐ and plurizoidangium‐bearing erect filaments, such filaments of E. nigra developing from wide erect filaments and those of E. orbicularis developing directly from basal prostrate filaments. However, many specimens investigated in the present study showed forms intermediate between these two patterns. Molecular phylogenetic analyses (including five additional elachistacean species) based on the internal transcribed spacer (ITS)2 region of the nuclear ribosomal RNA (nrRNA) gene showed a close relationship between all samples of E. nigra and E. orbicularis, and that the developmental patterns of paraphysis‐ and plurizoidangium‐bearing erect filaments were homoplasious. On the basis of these morphological and molecular data, E. orbicularis was reduced to synonymy with E. nigra. The ITS2 sequences of E. nigra were significantly different between samples from the Sea of Japan and those from the Pacific Ocean with several insertion/deletion and substitution mutations.  相似文献   

12.
13.
The lesser Egyptian jerboa Jaculus jaculus is a desert dwelling rodent that inhabits a broad Arabian–Saharan arid zone. Recently, two distant sympatric lineages were described in North‐West Africa, based on morphometric and molecular data, which may correspond to two cryptic species. In the current study, phylogenetic relationships and phylogeographical structure among those lineages and geographical populations from North Africa and the Middle East were investigated. The phylogeographical patterns and genetic diversity of the cytochrome b gene (1110 bp) were addressed on 111 jerboas from 41 localities. We found that the variation in Africa is partitioned into two divergent mitochondrial clades (10.5% divergence relating to 1.65–4.92 Mya) that corresponds to the two cryptic species: J. jaculus and J. deserti. Diversifications within those cryptic species/clades were dated to 0.23–1.13 Mya, suggesting that the Middle Pleistocene climatic change and its environmental consequences affected the evolutionary history of African jerboas. The third distant clade detected, found in the Middle East region, most likely represents a distinct evolutionary unit, independent of the two African lineages. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, ??, ??–??.  相似文献   

14.
As shown by morphological and molecular (ITS, nrLSU and tef1 sequences) evidence, the current concept of Myxarium nucleatum covers four species in the Nordic countries: M. cinnamomescens, M. hyalinum, M. nucleatum s.s. and M. populinum. These species are redescribed here, their nomenclature is discussed and all relevant names are typified. Exidia cartilaginea and E. villosa are typified and shown to be conspecific with the North American species E. candida. Based on morphological differences, E. cartilaginea is retained as a variety of E. candida. Exidia subrepanda is treated as a synomym of E. saccharina, and Heterochaete europaea as a synomym of E. thuretiana.  相似文献   

15.
Rhabdosciadium urusakii E. Akal?n sp. nov. (Apiaceae) is described and illustrated. It occurs very locally on scree slopes in Kemaliye (Erzincan), east Anatolia. This slender species is closely related to R. aucheri (Iran) and R. oligocarpum (south Anatolia). It is a very rare and critically endangered species. A key to all Rhabdosciadium species is given in this paper. The new species is characterized by dichotomous branched, long petiolate, pinnate and linear leaves, ovate‐lanceolate bracts, a brownish band and hairs on the dorsal side of the petals.  相似文献   

16.
Laurencia majuscula has recently been determined to be conspecific with Laurencia dendroidea. To determine the correct taxonomic placement of its only non‐typical variety, L. majuscula var. elegans, mitochondrial COI‐5P and chloroplast rbcL gene sequences were analyzed and its phylogenetic position was inferred. Laurencia majuscula var. elegans consistently formed a well‐supported clade distinctly separate from the L. dendroidea clade. Molecular analyses revealed that L. majuscula var. elegans generally shows two distinct forms; a long‐branched form, and a compact form. Often the compact form has been identified as a different species based on morphology alone. Included in these analyses were topotype sequences of two species with which L. majuscula var. elegans is most often misidentified; Laurencia nidifica and Laurencia mcdermidiae. Laurencia nidifica formed a well‐supported clade separate from L. majuscula var. elegans. Laurencia mcdermidiae, however, formed a well‐defined clade sister to the L. majuscula var. elegans clade. Morphological comparisons were also made. It is concluded that L. majuscula var. elegans is morphologically distinct from L. dendroidea, L. nidifica, and L. mcdermidiae. It is proposed that L. majuscula var. elegans be reinstated to species level as L. elegans.  相似文献   

17.
18.
The snake-eyed lizards of the genus Ophisops (Lacertidae) have been through a series of taxonomical revisions, but still their phylogenetic relationships remain uncertain. In the present study we estimate the phylogeographic structure of O. elegans across its distributional range and we evaluate the relationships between O. elegans and the sympatric, in North Africa, species O. occidentalis, using partial mtDNA sequences (16S rRNA, COI, and cyt b). All phylogenetic analyses produced topologically identical trees where extant populations of O. elegans and O. occidentalis were found polyphyletic. Taking into account all the potential causes of polyphyly (introgressive hybridization, incomplete lineage sorting, and imperfect taxonomy) we suggest the inaccurate taxonomy as the most likely explanation for the observed pattern. Our results stress the need for re-evaluation of the current taxonomical status of these species and their subspecies. Furthermore, our biogeographic analyses and the estimated time of divergences suggest a late Miocene diversification within these species, where the present distribution of O. elegans and O. occidentalis was the result of several dispersal and vicariant events, which are associated with climatic oscillations (the late Miocene aridification of Asia and northern Africa) and paleogeographic barriers of late Miocene and Pliocene period.  相似文献   

19.
Zhou, H., Fend, S. V., Gustafson, D. L., De Wit, P. & Erséus, C. (2010). Molecular phylogeny of Nearctic species of Rhynchelmis (Annelida). —Zoologica Scripta, 39, 378–393. The Nearctic species of Rhynchelmis (Clitellata, Lumbriculidae) are known primarily from cool‐water habitats in western North America. Their taxonomy has so far been based on limited collections from isolated localities, using intuitive assessment of morphological characters. This approach has proved unsatisfactory when additional populations of closely related species were sampled and scrutinized for incorporation in the present classification. Therefore, in this study, mitochondrial (cytochrome c oxidase subunit I and 16S rDNA) and nuclear internal transcriber spacer (ITS rDNA) genes were analysed as phylogenetic markers of Nearctic Rhynchelmis species. A combined approach with all the three gene regions provided a better resolution than any of the individual genes by itself. The genes demonstrated monophyly of all major groupings proposed on the morphological basis. Within the Rhynchelmis yakimorum complex, however, the genetic data and distribution suggested that two clades initially referred to as a ‘R. yakimorum variant 1’, one from the lower Snake River drainage in Idaho and one from southern coastal Oregon, might represent two separate species. On the other hand, the sympatric distribution and low genetic distance between Rhynchelmis gustafsoni and a form tentatively identified as ‘R. cf. yakimorum’ (both collected in eastern Idaho) indicated conspecific status. This study also showed that the cytochrome c oxidase subunit I (COI) gene, which may be informative of recent and on‐going speciation and useful for species discrimination (as a DNA barcode), is less suitable as a single molecular marker for phylogenetic inference. Regardless of whether one deals with very closely related species (such as those of the yakimorum complex), with taxa with a wide and disjunct distribution (such as Rhynchelmis rostrata), or with more distantly related species, COI data should be supplemented by other genetic markers as well as morphological and biogeographical information.  相似文献   

20.
In a survery of the bee fauna of Horand forests in East Azerbaijan province of Iran during 2008 and 2009, 46 species belonging to the families Anthophoridae, Halictidae and Megachilidae were identified. Eight species are new to the fauna of Iran: Evylaeus albipes (Fabricius, 1781), E. corvinus (Morawitz, 1878), E. israelensis (Ebmer, 1974), Seladonia desertorum (Morawitz, 1876), Heriades crenulatus Nylander, 1856, Hoplitis anthocopoides (Schenck, 1853), H. manicata (Morice, 1901) and H. rufohirta (Latreille, 1811).  相似文献   

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