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1.
Uredinia and urediniospores of six Puccinia species growing on Poaceae in southwestern Saudi Arabia were morphologically compared by light and scanning electron microscopy (SEM). Puccinia cenchri, P. fragosoana and P. isiacae were recorded for the first time in Saudi Arabia. Many differences between uredinia and urediniospores of studied Puccinia species were recorded. These differences are not related to host plant but may be due to the species of Puccinia itself. Observations by SEM led to more information in distinguishing between these Puccinia species particularly the presence of paraphyses and density and length of spines.  相似文献   

2.
Dr. Saleh M. Okla 《Facies》1992,27(1):217-223
Summary Late Permian bioclastic calcarenite beds of the middle Khuff Formation were sampled for their algal constituents near the city of Unayzah, Quassim district in central Saudia Arabia. The algal flora includes two species of udoteacean algae (Succodium difficile andSuccodium sp.), the dasycladacean algaMizzia velebitana and two species of red algae (Gymnocodium bellerophontis, Permocalculus plumosus). Other algal floral remains found forming isolated single layers which have generally been named algal microfacies. These include a phylloid microfacies, an oncoid microfacies and algal stromatolites. The Khuff Formation is well-known for its accumulation of non-associated gas and particularly for its oil accumulation in eastern Saudi Arabia and the Arabian Gulf states.  相似文献   

3.
Asaccus geckos are distributed in southwest Asia, mainly in Iran and Arabia. Currently, seven Asaccus species are recognized in Arabia, all endemic to the isolated Hajar Mountains in Oman and the UAE, an area regarded as a biodiversity and endemicity hotspot. Previous phylogenetic studies have shown a non‐monophyletic structure of the Arabian Asaccus species, with the Hajar endemic A. montanus diverging first from the remaining Iranian and Arabian taxa, thus suggesting a possible Arabian origin for the genus. Despite the species’ obvious phylogeographical importance, no study has yet explored its intraspecific diversity. In this study, we assessed the genetic diversity and phylogeography of A. montanus and its phylogenetic relationships with the rest of the Arabian Asaccus species and some available representatives from Iran. We used both mitochondrial and nuclear data to assess phylogenetic relationships based on haplotype networks, concatenated datasets and species trees, performed species delimitation analyses, and estimated divergence times and genetic diversity. We suggest Asaccus began diverging during the Middle Oligocene, a period of major tectonic activity in and around Arabia. Our results mainly support previous phylogenetic studies and uncover the presence of cryptic diversity within A. montanus. Asaccus montanus diverged in the Jebel Akhdar Mountain range into two deep allopatric lineages during the Late Pliocene. Our findings suggest further taxonomic research is necessary for this species, especially due to its vulnerable status and restricted range in an area of great conservation importance.  相似文献   

4.
Members of the Eurasian (or Common) Reed Warbler complex, Acrocephalus scirpaceus, are widespread across much of Europe, Africa, the Middle East and Central Asia. With its relatively complex taxonomy, the identity of several local (and sometimes remote) populations remains somewhat unresolved. In Saudi Arabia, populations of reed warblers were first identified in mangroves at Yanbu’ on the Red Sea coast in 1984, with several subsequent records up to 900 km further south toward the Yemen border. We took morphological data from 51 individuals and genetic material from three individuals captured near Jazan in southwest Saudi Arabia. Both genetic and morphometric data confirmed that these birds belong to the taxon A. scirpaceus avicenniae, sometimes referred to as the Mangrove or Red Sea Reed Warbler.  相似文献   

5.
A small collection of cephalopods from the middle Ordovician of the Tabuk region of Saudi Arabia consists entirely of orthoconic longicones tentatively referred to the actinocerid genus Mesaktoceras? and pseudorthocerid Sactoceras?. Both taxa have Australasian affinities. Circumpolar Gondwana cephalopod faunas in the mid Ordovician were of low diversity and dominated by orthocerids, whilst actinocerids were largely restricted to low palaeolatitudes. The presence of Mesaktoceras? and Sactoceras? in a benthonic fauna belonging to the Neseuretus community is regarded as anomalous. Comparison is made with the occurrence of Trocholites in middle Ordovician Iberian successions. It has been suggested that Trocholites may have arrived in the Iberian area from Baltica through the transfer of bodies of warm water in storm masses. Mesaktoceras? and Sactoceras? may have arrived (albeit temporarily) in Saudi Arabia from Australasia through a similar process.  相似文献   

6.
Male and female specimens of Meriones rex were collected from agricultural areas of Asir province in Saudi Arabia. The mitotic and meiotic chromosomes were analysed and the diploid number of chromosomes was found to be 38. The karyotype showed 24 metacentric, 10 submetacentric and 2 acrocentric autosomes. The sex chromosomes were represented by a medium-sized metacentric X and a small metacentric Y chromosome. The fundamental number (FN) was 74.This project has been supported by Research Center of College of Science, King Saud University (Zoo/1402/11), Riyadh, Saudi Arabia.  相似文献   

7.
A 12 month period survey of the fungi associated with Euphorbia inarticulata was evaluated. Sampling was concentrated mainly in Aseer region (South-West Saudi Arabia) and seven fungal species were identified as pathogens of this plant. Melampsora euphorbiae and Alternaria euphorbiicola were the most common species on this plant. Bipolaris euphorbiae, Botrytis ricini, Colletotrichum gloeosporioides, Oidium sp., Sphaceloma poinsettiase and Uromyces euphorbiae were less frequent species. These fungal pathogens were recorded for the first time on Euphorbia inarticulata in Saudi Arabia. Scanning and transmission electron microscopy revealed the colonization of M. euphorbiae, as an example, in leaf tissues of E. inarticulata. Remarkable ultrastructural changes in chloroplasts and nuclei of infected cells of E. inarticulata as a result of infection by M. euphorbiae were observed.  相似文献   

8.
An analysis was made of the R- and C-banding of chromosomes of the following Gerbillus species (Rodentia, Gerbillidae): G. poecilops (Taif, Saudi Arabia), G. henleyi (Oursi, Burkina Faso; Kairouan, Tunisia), and G. nanus (Taif and Hofuf, Saudi Arabia; Sind desert, Pakistan). Their karyotypes show the same chromosome number (2n = 52), but a different N.F.a. (number of autosomal arms), ranging from 58 to 62 in the species overall, and from 58 to 60 among G. nanus forms, due to pericentric inversions involving chromosomes 1 and 4. Moreover, large inter-individual variations of heterochromatin segments of chromosomes 25, X, and Y were found. Considering morphology and karyotype, G. poecilops and G. henleyi appear to be rather monomorphous species, whereas G. nanus produces a series of forms as a consequence of speciation, in which both chromosomal and morphological differentiations occur that do not correlate.  相似文献   

9.
Thirty-four genera and 80 species in addition to one variety of A. nidulans were identified from 40 soil samples colleted from different places in desert of Saudi Arabia. More than forty-two species are new records from Saudi Arabian soils. Aspergillus and Penicillium contributed the greatest number of species (15 species + 1 variety and 13 species respectively).The most frequent genera were Aspergillus, Penicillium, Botryotrichum, and Ulocladium followed by Macrophomina, Rhizopus, Fusarium, Alternaria and Cladosporium from which A. fumigatus, A. terreus, A. niger, A. flavus, P. citrinum, P. corylophilum, B. atrogriseum, U. botrytis, M. phaseoli, R. stolnifer, F. moniliforme, A. alternata and C. herbarum were the most common.Comparison between the present results and those of the other studies showed that there is no fungal flora characteristic of desert soils of Saudi Arabia.  相似文献   

10.
Abstract

Red date palm weevil Rhynchophorus ferrugineus Oliv. is a widespread major pest of date palm in the Kingdom of Saudi Arabia. Three different forms (black and brown with and without spots on thoracic region) were investigated using PCR-based RAPD technique. Although weevils were collected from the same geographical region of Al-Hassa in Saudi Arabia, the banding profile acquired suggested that black and brown colored morphs are genetically closer compared to the brown with spots. Intra color variation remained minimum in black but brown and brown spotted morphs exhibited more genetic variation. This genetic variation may be either due to the generation of new mutants from the non-spotted or spotted weevil or they may belong to a different race.  相似文献   

11.
Mosquitoes (Diptera: Culicidae) are considered to be huge threat among millions of peoples, animals, and other living organisms in the world. Most of the vector borne diseases such as malaria, filariasis, dengue hemorrhagic fever, chikungunya, Japanese encephalitis etc., created huge impact on humans in all over the world. Vector diseases in Kingdom of Saudi Arabia are increasing day by day and their control measures taken through the government sectors for eradicating the vectors helps in controlling the diseases but still more approaches to be implemented or assimilated. Most of the synthetic or chemical based insecticides to control mosquitoes developed resistance among their communities even though they showed their potential in controlling the vector in initial days. Botanical insecticides from plant-based origin such as active compounds, essential oils, green synthesized nanomaterials, and microbial secondary metabolites helps more efficiency in controlling vectors. Mode of action against vectors differs based on its persisting active ingredients, such as larvicidal, pupicidal, adulticidal, oviposition, morphological changes etc. Even though number of research works has been carried out against mosquito species, there is only limited number of studies undergone against mosquito vectors from Saudi Arabia origin. Hence this review will give us the current knowledge on the effectiveness of botanical insecticides against major mosquito vectors from Saudi Arabia. Thus, it gives more significant against medical and veterinary sectors.  相似文献   

12.
Aerial exposure of patch reef corals occurred in Tarut Bay, western Arabian Gulf, (Saudi Arabia) between December 1991 and May 1992, and coincided with extreme low spring tides (below the predicted lowest astronomical tide-LAT). Colonies of Acropora and Stylophora occurring at the highest levels on the tops of patch reef platforms were most affected by the low tides. Corals fully exposed to air suffered total mortality, whereas those not fully exposed suffered tissue damage to their upper parts. Exposure occurred during winter months when air and water temperatures are at their lowest in the gulf. Coupling of extremely low spring tides with wind-induced negative surges (below LAT) are not regular events but are not infrequent. Cold temperatures and exposure may act in concert to produce disproportionate mortalities of reef flat corals in the shallow coastal areas of eastern Saudi Arabia. It is highly unlikely that the Gulf War oil spill played any role in the observed damage to reef corals in the Gulf in 1992.  相似文献   

13.
Sarcostemma areysianum Bruyns is described from the southern mountains of Yemen. It appears to be most closely related to S. arabicum Bruyns & P. Forst. and S. socotranum Lavranos, differing from both by the taller gynostegium with narrow, mostly acute inner corona lobes. A key to the species from Arabia and Socotra is provided.  相似文献   

14.
Phagnalon rechingeri spec. nova from S Baluchestan (Iran) is described as a species new to science and illustrated; its relationships to other species of the genus, in particular to thePh. woodii group from S Arabia, are discussed.Dedicated to Hofrat Univ.-Prof. DrK. H. Rechinger on the occasion of his 80th birthday.  相似文献   

15.
Boromophus saudicus sp. n. (subfamily Pimeliinae Latreille, 1802, tribe Boromorphini Skopin, 1978) is described from the Kingdom of Saudi Arabia (Rawdhat Khorim, Riyadh Province). This finding represents the first record of the genus Boromorphus Wollaston, 1854 from the Arabian Peninsula. The species was collected from Acacia trees and from pitfall traps.  相似文献   

16.
Almost 20% of Oman’s terrestrial reptiles are found on Masirah Island. Despite its ancient geological history and its long isolation, Masirah Island only harbours one endemic reptile species, Hemidactylus masirahensis. In this study, we use an integrative approach to explore the variation in Pristurus minimus, to revise its systematics and to assess its phylogeography by using molecular (mitochondrial and nuclear DNA sequences) and morphological data. Our results uncovered a deep divergence within P. minimus that dates back to ~4?Ma, during the Pliocene Epoch. The old divergence separated P. minimus into two allopatric species: one from mainland Arabia, P. minimus, and one endemic to Masirah Island, described as a new species herein. Despite the general similarity between the two sister species, there are morphological differences related mainly to body size. The new Pristurus species endemic to Masirah Island is significantly smaller than its mainland sister taxon, becoming the smallest known vertebrate species in Arabia and one of the smallest lizard species in the world. The phylogenetic analyses also uncovered a low level of genetic diversity within the newly described Pristurus species endemic to Masirah Island and a relatively deep genetic divergence within P. minimus that dates back to the Pleistocene. Once more, the present study highlights the relatively high levels of reptile diversity and endemicity in south-eastern Arabia despite its harsh, arid climate and stresses its relevance from a conservation point of view.

The LSIDs for this publication is: urn:lsid:zoobank.org:pub:DB0658D5-7F68-4E66-885F-75E27F9CD512.  相似文献   

17.
Eighteen scleractinian coral species belonging to 13 genera, 8 families and 4 suborders have been identified from the lower and upper parts of the Upper Jurassic (Oxfordian) Hanifa Formation at Jabal Al-Abakkayn, central Saudi Arabia. Actinastrea bernensis, A. crassoramosa, Coenastraea hyatti, Stylina kachensis, Cryptocoenia slovenica, C. wegeneri, Isastrea hemisphaerica, I. bernensis, Montlivaltia cornutiformis, M. frustriformis, Collignonastraea jumarensis, Ovalastrea michelini and Vallimeandropsis davidsoni are believed to be recorded for the first time from the Jurassic rocks of central Arabia. Most corals have massive hemispherical and globular forms, and few corals have dendroid and conical growth forms. They occur as small, isolated patches, about 0.5 m thick and about 10–30 m wide, in argillaceous reefal limestones. The identified corals show Africa, north America, northern, southern and western Europe, and southern or eastern Asia corals. The low diversity and abundance as well as the small size of colonies are attributed to inimical palaeoecological factors throughout the reefoids formation such as muddy substratum, water turbidity, high rate of sedimentation.  相似文献   

18.
Colletotrichum lindemuthianum isolated from soybean in Saudi Arabia produced polygalacturonase, pectin methylesterase, pectin trans-eliminase and carboxymethylcellulasein vitro. Polygalacturonase showed maximaum activity at 30 to 35°C and pH 4.0 to 5.0. The absorption maximum for pectin trans-eliminase reaction products was at approximately 548 nm. The polygalacturonase and pectin trans-eliminase activities increased with culture age. The degradation of carboxymethylcellulose was also demonstrated.  相似文献   

19.
Three specimens of the blackfin coral goby, Paragobiodon lacunicolus, were collected in 2010 and 2011 at different locations of the eastern Red Sea along the coast of Saudi Arabia. Reexamination of 14 museum specimens from Eritrea also confirmed the presence of the species for the western Red Sea. This represents the first published report of P. lacunicolus from the Red Sea.  相似文献   

20.
The Persian Horned Viper (Pseudocerastes persicus) is distributed from northeast Iraq through the Iranian Plateau to western Pakistan with isolated populations in the Hajar Mountains of south-eastern Arabia. Like the other members of the genus Pseudocerastes, P. persicus is a sit-and-wait ambush feeder with low vagility, a characteristic that often results in high levels of population differentiation. In order to clarify the level of genetic variability, phylogenetic relationships, and biogeography of the Arabian populations of P. persicus we sequenced 597 base pairs of the mitochondrial cytochrome b of four individuals from the Hajar Mountains in south-eastern Arabia and inferred their phylogenetic relationships including 10 samples of P. persicus from Iran and Pakistan, four P. urarachnoides and one P. fieldi downloaded from GenBank. The four Arabian samples are genetically very similar in the gene fragment analysed and are phylogenetically very closely related to populations of P. persicus from coastal south Iran. Biogeographically, it appears that colonisation of the Hajar Mountains by P. persicus took place from Iran very recently, most probably during the last glaciation, when most of the Persian Gulf was above sea level and did not represent a barrier for dispersal.  相似文献   

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