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1.
The tadpole shrimp Triops cancriformis (Branchiopoda, Eucrustacea) is often referred to as a “living fossil.” This term implies that the morphology of a species has barely changed for hundreds of millions of years; in the case of T. cancriformis, for about 200 million years. In 1938, Trusheim documented fossil notostracans from the Upper Triassic of southern Germany (237–200 million years) and named them T. cancriformis minor due to their small size compared to modern forms of T. cancriformis. We compared the ontogenetic sequence of the fossil forms to that of modern forms. Fossil material came from the Museum Terra Triassic in Euerdorf and originated from the same geological formation (the Hassberge Formation) as the Trusheim material, which is considered to be nearly entirely lost. The specimens were documented using cross-polarized light and processed into high-resolution images. Fluorescence microscopy was used to document exuviae and carcasses of extant representatives of T. cancriformis. Both forms showed an elongation and similar trends in the length/width ratio of the shield during ontogeny. However, differences were found in the starting point of the developmental processes. Fossil forms start out with a more roundly shaped shield, which becomes more elliptical, while extant forms already start with a more elliptical shield shape. Further differences between extant and fossil forms were found upon comparing shield to trunk ratios. All differences are highly significant statistically. These differences in ontogeny cast severe doubt on the interpretation that T. cancriformis has been static for 237 million years. While the term “living fossil” is misleading and its use should be discouraged in general, it seems to be especially inappropriate to apply it to T. cancriformis.  相似文献   

2.
Central Himalayan region of India encompasses varied ecological habitats ranging from near tropics to the mid-elevation forests dominated by cool-temperate taxa. In past, we have reported several new records and novel species from Uttarakhand state of India. Here, we assessed genetic variations in three mitochondrial genes, namely, 16S rRNA, cytochrome c oxidase subunit I and cytochrome c oxidase subunit II (COI and COII) in 26 drosophilid species collected along altitudinal transect from 550 to 2700 m above mean sea level. In the present study, overall 543 sequences were generated, 82 for 16S rRNA, 238 for COI, 223 for COII with 21, 47 and 45 mitochondrial haplotypes for 16S rRNA, COI and COII genes, respectively. Almost all species were represented by 2–3 unique mitochondrial haplotypes, depicting a significant impact of environmental heterogeneity along altitudinal gradient on genetic diversity. Also for the first time, molecular data of some rare species like Drosophila mukteshwarensis, Liodrosophila nitida, Lordiphosa parantillaria, Lordiphosa ayarpathaensis, Scaptomyza himalayana, Scaptomyza tistai, Zaprionus grandis and Stegana minuta are provided to public domains through this study.  相似文献   

3.
The present communication deals with recording of nine species of soldier flies (Insecta: Diptera: Stratiomyidae) from Sunderban Biosphere Reserve of India, of which, Tinda indica (Walker, 1851), Hermetia illucens (Linnaeus, 1758), Odontomyia kashmirensis Brunetti, 1920, Odontomyia viridana (Wiedemann, 1824), Prosopochrysa vitripennis (Doleschall, 1856) are being reported for the first time from this unique and globally acclaimed mangrove ecosystem. Odontomyia kashmirensis Brunetti, 1920 is reported for the first time from the state of West Bengal. A key to identify these species is provided with taxonomic notes.  相似文献   

4.
5.
Two new species viz., Acaricalus indicus n. sp. from Fern (indet) and Neooxycenus dilleniae n. sp. from Dillenia pentagyna Roxb. (Dilleniaceae) are described from West Bengal. Four species viz., Acaphyllisa araucuriae Flechtmann (2000), Aculops pretoriensis Smith Meyer and Ueckermann (1990), Tetra tyrohylae Smith Meyer (1992) and Tetra visci Smith Meyer (1992) are recorded for the first time from India. Besides, 23 other species are reported for the first time from West Bengal. An eriophyoid species is recorded for the first time from a species of Fern in India.  相似文献   

6.
Availability of molecular methods, gene sequencing, and phylogenetic species recognition have led to rare fungi being recognized as opportunistic pathogens. Fungal keratitis and onychomycosis are fairly common mycoses in the tropics, especially among outdoor workers and enthusiasts. The frequently isolated etiological agents belong to genera Candida, Aspergillus, and Fusarium. Within the genus Fusarium, known to be recalcitrant to prolonged antifungal treatment and associated with poor outcome, members of the Fusarium solani species complex are reported to be most common, followed by members of the Fusarium oxysporum SC and the Fusarium fujikuroi SC (FFSC). Morphological differentiation among the various members is ineffective most times. In the present study, we describe different species of the FFSC isolated from clinical specimen in south India. All twelve isolates were characterized up to species level by nucleic acid sequencing and phylogenetic analysis. The molecular targets chosen were partial regions of the internal transcribed spacer rDNA region, the panfungal marker and translation elongation factor-1α gene, the marker of choice for Fusarium speciation. Phylogenetic analysis was executed using the Molecular Evolutionary Genetics Analysis software (MEGA7). In vitro susceptibility testing against amphotericin B, voriconazole, posaconazole, natamycin, and caspofungin diacetate was performed following the CLSI M38-A2 guidelines for broth microdilution method. The twelve isolates of the FFSC were F. verticillioides (n = 4), F. sacchari (n = 3), F. proliferatum (n = 2), F. thapsinum (n = 1), F. andiyazi (n = 1), and F. pseudocircinatum (n = 1). To the best of our knowledge, this is the first report of F. andiyazi from India and of F. pseudocircinatum as a human pathogen worldwide. Natamycin and voriconazole were found to be most active agents followed by amphotericin B. Elderly outdoor workers figured more among the patients and must be recommended protective eye wear.  相似文献   

7.

Key message

Genetic structure among M. azedarach populations was detected and two subpopulations were present among them. A significant ‘isolation by distance’ was found in M. azedarach population in North-Western Plains of India.

Abstract

Melia azedarach is an important forest tree with pharmaceutical, insecticidal, pesticidal, and commercial significance. It is a good reforestation tree because of its fast growth and drought hardy nature. Genetic variation in a species allows itself to adapt, evolve and respond to environmental stress. It provides the basis for survival of a species and critically influences its evolutionary potential. Assessment of genetic diversity is necessary for improvement and conservation of a species. For this, microsatellite markers are of particular interest given the attributes like co-dominance, reproducibility, hyper variability and abundance throughout the genome. In the present study, we analyzed the genetic diversity and population structure of M. azedarach, an ecologically imperative species growing in the North-Western Plains of India. We developed 43 microsatellite markers, of which 20 were subsequently employed for analysis of diversity and population structure among 33 populations encompassing 318 genotypes representing North-Western Plains of India. A moderate level of diversity (Na = 5.1, Ho = 0.506, He = 0.712, I = 1.386) was assessed. The highest value of ΔK estimated using STRUCTURE indicated 2 subpopulations (K = 2). AMOVA exhibited 73 % variation within populations and 12 % variation was found among regions. Significant positive correlation between geographical and genetic distance was found (Rxy = 0.365, P = 0.010). The present study lays a foundation on a better understanding of genetic dynamics of the species and reveals its diversity and population structure in North-Western Plains of India.
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8.
Although mutualism between ants and flowering plants is wide spread, ant pollination has not evolved as a major pollination syndrome. So far ant pollination has been reported largely in herbaceous species, growing in warm and dry habitats. While studying pollination ecology of Syzygium species (Myrtaceae), growing in tropical forests of the Western Ghats, India, we observed one of the ant species, Technomyrmex albipes, to be the dominant floral visitor in S. occidentale (Bourd.) Chithra among a range of other insect (species of Xylocopa and Trigona, and Apis cerana) and bird visitors. We studied the role of ant species in pollination when compared to other floral visitors. The fruit set in flowers exclusively visited by T. albipes was significantly higher than those visited by any other visitor. The day and night exclusive pollination experiments allowing only T. albipes indicated diel pollination by T. albipes, which was the only active flower visitor during the night. The breeding system of the species was studied through controlled pollinations. The species is partially self-compatible and exhibits considerable autogamy.  相似文献   

9.
Endelus (Kubaniellus) indicus sp. n. from India, E. (K.) lao sp. n. and E. (K.) khnzoriani sp. n. from Laos, E. (s. str.) sausai sp. n. from China, and E. (s. str.) dembickyi sp. n. from India are described, the two latter species are included in the Endelus bicarinatus Théry, 1932 species-group recently established by the author. E. collinus Obenberger, 1922 is included in this group; lectotype of this species is designated. Keys to species of the subgenus Kubaniellus and of the E. collinus group are provided. E. (K.) kareni Kalashian is for the first time recorded for Shaanxi Prov., E. pacholatkoi Kalashian, E. smaragdinus Desc. et Vill., and E collinus Obenb., for Laos (the latter species, also for Myanmar).  相似文献   

10.
Hybridization is regarded as a rapid mechanism for increasing genetic variation that can potentially enhance invasiveness. Tamarix hybrids appear to be the dominant genotypes in their invasions. Exotic Tamarix are declared invasive in South Africa and the exotic T. chinensis and T. ramosissima are known to hybridize between themselves, and with the indigenous T. usneoides. However, until now, it was not known which species or hybrid is the most prevalent in the invasion. With a biocontrol programme being considered as a way of suppressing the alien Tamarix populations, it is important to document the population genetic dynamics of all species in the region. This investigation sought to identify Tamarix species in southern Africa and their hybrids, describe their population structure, and reveal the geographic origin of the invasive species. To achieve this, nuclear Internal Transcribed Spacer (ITS) sequence data and the multilocus Amplified Fragment Length Polymorphisms (AFLPs) markers were used. Phylogenetic analysis and population genetic structure confirmed the presence of three species in South Africa (T. chinensis, T. ramosissima and T. usneoides) with their hybrids. The indigenous T. usneoides is clearly genetically distant from the alien species T. chinensis and T. ramosissima. Interestingly, the Tamarix infestation in South Africa is dominated (64.7 %) by hybrids between T. chinensis and T. ramosissima. The exotic species match their counterparts from their places of origin in Eurasia, as well as those forming part of the invasion in the US.  相似文献   

11.
Litsea glutinosa (Lour.), one of the most dwindling forest species in central India, is represented by highly fragmented populations that have been drastically reduced for the last 40 years, promulgating government ban on its extraction. For the first time with the help of ISSR markers, we investigated genetic variation and population structure of L. glutinosa in central Indian states. A total of 84 genotypes from 10 populations covering the entire potential pockets of the species in central India were collected. The percentage of polymorphic loci ranged from 44.79% (Rewa) to 94.79% (Marvahi) with a mean value of 70.10%. The sampled populations harbored high level of genetic diversity (mean h?=?0.294 and I?=?0.424) that was partitioned more within populations (73%) than between populations (27%). Bayesian structure analysis revealed the existence of four admixed genetic pools in L. glutinosa. The unsustainable extraction rather than genetic factor seems to be responsible for population fragmentation and dwindling status of this species. The dioecious nature of the species advocates an in-situ conservation to be the most suited approach for which Chhindwara, Jagdalpur, Balaghat and Jabalpur populations are appropriate.  相似文献   

12.
The monotypic genus Spathebothrium Linton, 1922 contains the only known species Spathebothrium simplex Linton, 1922. In this paper Spathebothrium vivekanandai sp.n. is described and illustrated. The specimen was obtained from the intestine of a freshwater fish Channa striatus which was collected from Basirhat, North 24 Parganas, West Bengal, India. The species is characterized by a small scolex, rounded anteriorly; presence of neck; genital pores irregularly or regularly alternate and U-shaped ovary. In addition to these characters, absence of vaginal sphincter and absence of seminal receptacle differentiates the present species from the earlier described one. The genus Spathebothrium Linton, 1922 is being reported for the first time from West Bengal, India.  相似文献   

13.
Present work is a part of our studies on the cytological details of some species of Artemisia L. inhabiting Ladakh region of Jammu and Kashmir state. Of the six populations investigated for three different species (Artemisia sieversiana Ehrh. ex Willd., A. tournefortiana L. and A. gmelinii Weber ex Stechm.), some variations were noticed only for Artemisia gmelinii. The species occurring in Leh region at altitudinal range of 3992 masl is diploid with 2n = 18 (n = 9). In one of the population of the species, sprawling in Hemis region (4009 masl), В chromosome was found to be present in addition to the diploid chromosome complement. Comparison of the different morphological and reproductive features revealed that the population with В chromosome had reduced vigour.  相似文献   

14.
Here we report the results of an archaeobotanical study carried out on Ceramic Neolithic (2700–2000 bc) and Kushan period (ad 100–300) deposits at Kanispur, Kashmir, northern India. Botanical evidence from the Ceramic Neolithic phase reflects a nascent agriculture based on cold-tolerant crops (barley, wheats, lentil, field pea and grass pea) related to farming patterns of adjacent cultures and possibly evidence for the earliest cultivation in the valley. The Kushan period is characterized by a double-cropping pattern, suggesting a change in agricultural practices associated with a population recovery following a post-Neolithic decline. Finds of Juglans regia, and Prunus cf. amygdalus shells in ceramic Neolithic levels, and Vitis cf. vinifera, Emblica officinalis and Ziziphus cf. nummularia in addition to J. regia, and P. cf. amygdalus during Kushan times suggest that horticulture and foraging played an important role in the diet of the occupants. The present dataset provides new absolute dates for the subsistence economy of the Ceramic Neolithic population in the Kashmir Valley. We also present the oldest directly dated wheat and barley in Kashmir.  相似文献   

15.
We evaluated the genetic diversity of the African poplar (Populus ilicifolia) populations found in Kenya compared with reference samples of five poplar species from North America and one species introduced in Kenya from India (KEFRI-Kenya). Amplified fragment length polymorphism (AFLP) was used with the objective of providing important information for breeding and in situ/ex situ conservation of this species. Samples collected from three locations along the species’ natural range (Athi, Ewaso Nyiro, and Tana rivers) were compared with four samples of locally planted Populus deltoides stand introduced from India and ten reference samples from North America. Six AFLP primer combinations produced 521 clear bands for analysis. The percentage polymorphic loci were lowest in Tana (20.4 %) and highest in Athi (40.6 %). The average heterozygosity across the studied populations was between 0.07 and 0.3. AMOVA revealed more genetic variation partitioning within population (87 %; P?<?0.01) than among populations (13 %; P?<?0.01) suggesting significant genetic variation between populations. Further, UPGMA delineation showed two clusters of the Tana, Athi, and Ewaso Nyiro populations clustered together compared to the North America and India/KEFRI reference samples. Moreover, the study showed that the Athi population is more diverse than those of Tana and Ewaso Nyiro and may be important for conservation, domestication, and improvement studies. The genetic differentiation (F ST ?=?0.134) among Kenyan P. ilicifolia populations suggests limited possibility of gene flow between these populations.  相似文献   

16.
The genus Anonchotaenia Cohn, 1900 contains 23 valid species. In this paper Anonchotaenia adhiraji sp.n. obtained from the intestine of a bird Hypsipetes madagascarensis commonly known as black bulbul from Bomdila in Dirang district of Arunachal Pradesh, India is described and illustrated.The species is characterized by a large unarmed, square-shaped scolex; testes 7–8 in number arranged in two lateral groups and a voluminous paruterine organ that differentiates it from the rest of the described species in the genus. This is also the first report of the genus Anonchotaenia Cohn, 1900 from Arunachal Pradesh, India.  相似文献   

17.
A novel saprobic fungal genus, Thyridariella (Thyridariaceae), is herein described to include Thyridariella mangrovei, the type species and T. mahakoshae spp. nov. Both species were collected as saprobes on decaying wood of Avicennia marina, a common mangrove species found near Kaveri River Delta, Tamil Nadu, on the east coast of India. Thyridariella is diagnosed by having an exclusive combination of characters, such as ascomata with ostiolar necks thickened laterally, hyaline, and centrally constricted muriform ascospores with a single longitudinal septum in each segment and surrounded by a mucilaginous sheath. These characters demarcate these taxa from morphologically similar genera such as Halojulella and Julella. In addition, the new genus also differs from Parathyridaria and Thyridaria in having hyaline, muriform ascospores with distinct mucilaginous sheaths. The monophyly of Thyridariella is well supported in the phylogenetic analysis based on a concatenated dataset from two proteins and three nuclear gene regions. The phylogeny also depicts a sister group relationship of our new genus to Parathyridaria and Thyridaria and hence confirms its position within Thyridariaceae.  相似文献   

18.
Mites of the genus Tyrophagus (Acari: Acaridae) are among the most widespread and common mites, inhabiting diverse natural and anthropogenic habitats. Some species are pests of agricultural products and stored food and/or live in house dust, causing allergies to humans. We sequenced 1.2 kb of the mitochondrial COI gene for 38 individuals belonging to seven species of Tyrophagus, including T. curvipenis, T. putrescentiae, T. fanetzhangorum, T. longior, T. perniciosus, and T. cf. similis. Molecular phylogenetic analyses (1) recovered two major clades corresponding to the presence or absence of eyespots, and (2) separated all included morphological species. Tyrophagus curvipenis and T. putrescentiae had the lowest between-species genetic distances (range, mean?±?SD): 14.20–16.30, 15.17?±?0.40 (K2P). The highest within-species variation was found in T. putrescentiae 0.00–4.33, 1.78?±?1.44 (K2P). In this species, we recovered two distinct groups; however, no geographical or ecological dissimilarities were observed between them. Based on our analyses, we document important morphological differences between T. curvipenis and T. putrescentiae. For the first time, we record the occurrence of T. curvipenis in the New World and suggest that it may be an emerging pest as it is currently spreading in agricultural produce.  相似文献   

19.
The purpose of this study was to evaluate the performance of Neoseiulus californicus (McGregor) for the control of Tetranychus urticae Koch in commercial strawberry fields, under greenhouse conditions, in association or not with the use of acaricides. The N. californicus strain used in this study was tolerant or resistant to several pesticides. Three experiments were carried out in the State of São Paulo, Brazil. For the first experiment, the initial infestation of T. urticae was 87.1 active stages per leaflet. Two applications of propargite were made on the first and the 14th day of the experiment. Approximately 2 h after each propargite application, N. californicus was released at a rate of 3.0 and 1.9 adult mites per plant, respectively, for each application. The population of T. urticae decreased from 87.1 to 2.8 mites per leaflet in the first three weeks. After this period, the population of T. urticae was maintained at low levels (≤1.5 mites/leaflet) until the end of the experiment (10th week). Propargite and dimethoate sprayed on the strawberry field did not affect significantly the population of this predaceous mite. For the second experiment, the infestation of T. urticae was 29.1 mites per leaflet, when the acaricide chorfenapyr was applied on the strawberry field. The release of N. californicus (2 mites per plant) was made 2 weeks after spraying the acaricide. The population of T. urticae was maintained at low levels (≤2.8 mites/leaflet) for 8 weeks (evaluation period). The T. urticae infestations in plots with N. californicus were significantly lower than in non-release plots, for the experiments 1 and 2. In the third experiment, the initial infestation of T. urticae was 40.5 mites per leaflet (55.5 active stages/leaflet on release plants; 25.5 active stages/leaflet on non-release plants). Three releases of N. californicus (average rate of 3.0 adult mites/plant), without any acaricide application, were not sufficient to reduce significantly the T. urticae population in release plots (release plants + non-release plants) in 6 weeks from the first release, however, the spider mite population decreased from 55.5 to 7.8 active stages per leaflet on release plants, during this period. Interplant dispersal of N. californicus was low in this strawberry field with high infestation of T. urticae. The studies indicate the viability of the use of this strain of N. californicus for the control of T. urticae in strawberry fields under greenhouse conditions, especially in association with selective acaricides.  相似文献   

20.
Sphenoptera (s. str.) galkae sp. n. from North Pakistan and. S. (s. str.) jacobsonorum sp. n. from India (Jammu and Kashmir State) are described and compared with closely related species. New synonymy is established for the following taxa: S. hypocrita Mannerheim, 1837 (= S. torrida Jakovlev, 1898; S. ixion Kerremans, 1912, synn. n.), S. bodemeyeri Jakovlev, 1900 (= S. quadrata Kerremans, 1909, syn. n.), S. exoleta Jakovlev, 1908 (= S. politipennis Obenberger, 1927, syn. n.), S. obruta Kerremans, 1909 (= S. chalcosoma Obenberger, 1927; S. abbreviata hetera Obenberger, 1927, synn. n.), S. tragacanthae (Klug, 1829) (= S. maledicta Obenberger, 1920; S. cilicica Obenberger, 1927; S. rambouseki Obenberger, 1927; S. klickai Obenberger, 1927; S. corrosa Obenberger, 1927; S. satrapa Obenberger, 1927; S. syriae Obenberger, 1927; S. vavrai Obenberger, 1927, synn. n.), S. magna Gory et Laporte, 1839 (= S. alexandri Obenberger, 1927, syn. n.). Lectotypes for 74 nominal species and subspecies are designated.  相似文献   

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