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1.
The diversity and distribution of the genus Tulipa in Uzbekistan are discussed; 34 taxa of Tulipa are recognized in Uzbekistan. The taxa were mapped using GIS software and their distributions were analyzed. Six species are endemic to the country. A national check‐list of Tulipa was created based on the classification developed by Zonneveld (2009). ‘Hot spot’ areas of tulip diversity in Uzbekistan are western Tien‐Shan (18 taxa), the western Pamir–Alay mountains (18 taxa) and the Turan lowland (5 taxa). An assessment of rare tulip species according to IUCN red list categories and criteria was performed for the first time for Uzbekistan. Evaluation of the latest classification of Tulipa clearly shows that further studies are required to arrive at a natural classification of the genus.  相似文献   

2.
Alburnoides holciki Coad & Bogutskaya, 2012 was originally described to be found in the Hari River basin. So far, this species is known to occur in tributaries of the Hari River in Afghanistan, Iran and Turkmenistan, and also in the upper reaches of the Amu Darya in Tajikistan. Populations from the inland waters of Uzbekistan were previously considered as A. eichwaldii. Our study recognized specimens of Alburnoides from the inland waters of Uzbekistan as A. holciki based on both morphological data and the molecular data. The novelty of the study is the confirmation of A. holciki for the inland waters of Uzbekistan, which constitutes the northernmost record of this species.  相似文献   

3.
Three species of Lophocharis (Rotifera: Monogononta), collected from lakes and ponds of Uzbekistan, are described. Two are new to science, and one is recorded for the first time from Uzbekistan. Some data on the variability of these species are given.  相似文献   

4.
The ability to competitively suppress native species is key to successful invasion. Since invasions involve an increase in abundance or dominance of a species in its non-native range, competitive effects might be expected to be stronger in the non-native range of an invader; however, there have been few comparisons of the competitive effects of invasive plants on species from invaded ranges versus species from native ranges. We compared the competitive and allelopathic effects of Acroptilon repens on native North American species to effects on related species from the native range of Acroptilon in Uzbekistan. We also compared the competitive interactions among these North American and Eurasian species, in the absence of Acroptilon, examining the hypothesis that particular regional species pools may show differences in competitive ability. The results showed that Acroptilon had stronger competitive effects against native North American species than against species native to Uzbekistan. There was no difference in the competitive effects among Eurasians and North Americans. The effects of leachates collected from Acroptilon roots were weak but more negative on species from North America than on species from Uzbekistan. Our results suggest that inherently stronger competitive and allelopathic effects of Acroptilon on North American plants than on plants from its native range may contribute to its invasive success.  相似文献   

5.
Three new species of the genus Dolichopus Latr. (Diptera, Dolichopodidae) are described. All these species are closely related to Dolichopus signifer Haliday, 1832 and form a species-group including this species. Dolichopus taimyricus sp. n. is described from the southern tundra of the Taimyr Peninsula (northern Central Siberia); D. zlobini sp. n. was collected in the Pamirs (Tajikistan) and D. asymmetricus sp. n., in the mountains of Kazakhstan, Tajikistan, and Uzbekistan. A key to all these species of the group is given.  相似文献   

6.
The paper `A taxonomic revision of the genus Taenia Linnaeus, 1758 s. str.' (Verster, 1969) gives concise characterisations, together with drawings of rostellar hooks and the terminal genital organs, of the 32 Taenia species and three subspecies which this author found to be valid. Yet, it is hardly possible to quickly identify a questionable species or to readily access information on their hosts, geographical range and synonyms. The present paper compiles these data and additional information on larval characteristics into tables. Measurements and numbers of hooks are shown using a graph. Additional data are included from authors not mentioned by Verster and for seven new species (T. dinniki, T. jaipurensis, T. kotlani, T. madoquae, T. saigoni and T. simbae), two re-validated species (T. krepkogorski, T. retracta) and two subspecies (T. polyacantha arctica and T. saginata asiatica) described since 1969. Reasons for rejecting one new species and one new subspecies are given. A table of definitive hosts and the Taenia species occurring in them is also included, as is one of synonyms from 1850 onwards. A good procedure for the staining and mounting of cestodes is described.  相似文献   

7.
No Devonian disparid crinoids have been described from Uzbekistan, although parahexacrinid thecae and assorted columnals have been described in several papers in the past 50 years. Discovery of a cup of Pisocrinus and a thecae of Haplocrinites are the first of these genera known from Uzbekistan. The stratigraphic range of Haplocrinites is revised to be late Early Devonian (Emsian) to Early Carboniferous (Tournaisian) because Silurian species assigned to the genus are based on loose ossicles that morphologically do not belong to the genus. The paleogeographic ranges of Pisocrinus and Haplocrinites are extended into Uzbekistan. Haplocrinites uzbekistanensis n. sp. is described.  相似文献   

8.
Tripsacum andersonii Gray (Gramineae) is a species with 2n = 64 chromosomes. Chromosome behaviour during meiosis of microsporogenesis suggests that the species combines three homologous haploid Tripsacum genomes of x = 18 (54 chromosomes), and an alien haploid genome of x = 10 chromosomes. Cytogenetic studies indicate that T. andersonii originated as a hybrid between a species of Tripsacum (2n = 36) and a species of Zea (2n = 20). Comparative morphology and flavonoid chemistry fail to identify the Zea species involved in this intergeneric hybrid. Chromosome morphology suggests that it was either Z. mays L. subsp. mays (domesticated maize) or subspecies mexicana (Schrad.) Iltis (annual teosinte). The Tripsacum parent probably was T. latifolium Hitchc. of Central America. It resembles T. andersonii in vegetative morphology. Tripsacum maizar Hernandez et Randolph and T. laxum Nash, which resemble T. andersonii in flavonoid chemistry, are eliminated as possible parents on the basis of growth habit and the morphology of their hybrids with maize.  相似文献   

9.
We investigated the floral characteristics, floral biology and floral visitors of the six Bornean Tacca species: T. bibracteata (only floral characteristics), T. borneensis, T. havilandii, T. leontopetaloides, T. palmata and T. reducta, and T. cristata from Peninsular Malaysia. All species are protogynous with pollen strings extruded post flower opening. Blooming of all species started from dawn except for T. leontopetaloides which flowered from dusk. While T. borneensis, T. cristata, T. havilandii, T. leontopetaloides and T. reducta are facultatively autogamic as the pollen/ovule ratios (P/O ratios) were low, T. bibracteata is facultatively xenogamic as its P/O ratio was higher. Four species (T. borneensis, T. cristata, T. havilandii and T. reducta) were tested for autonomous self-pollination but all failed to set fruit. Manual self- and cross-pollination treatments of T. borneensis, T. cristata and T. havilandii showed reduced fruit set and seed set. In contrast, T. reducta was highly self-compatible. The showy bracts and bracteoles of T. borneensis are needed to guarantee pollination success but is not so in the other species investigated. Tacca are pollinated by two pollination guilds of female midges: two species of Forcipomyia (Lasiohelea) and Culicoides hinnoi. The floral biology and mating system of Tacca species indicate that most fruits and seeds were produced in samples resulting from natural pollination.  相似文献   

10.
It is only in the Hawaiian Islands that species of the otherwise marine genus Telmatogeton have evolved into freshwater. An analysis of polytene chromosomes and karyotypes of two marine species and five freshwater species revealed that paracentric inversions and centric fusions were important in chromosomal evolution. The sequence of polytene chromosome bands common to most species, established as the Telmatogeton standard sequence, is found in a population of T. torrenticola from West Maui. Most species and other populations of T. torrenticola may be derived from the standard sequence by paracentric inversions. Similarities with the standard band sequence places T. japonicus (n=7) rather than T. pacificus (n=4) in the proposed phylogeny as the species closest to the marine ancestor of the freshwater species. One of three species (T. fluviatilis from Oahu, T. torrenticola from West Maui, or an undescribed species from East Maui), each with seven pairs of chromosomes is considered to be closest to the original freshwater species. T. torrenticola is a complex species in which there is an accumulation of fixed inversions and centric fusions in stepwise fashion in populations from west to east (West Maui n=7; East Maui n=6; Kohala Mountains n=5 and Mauna Kea n=4 both from the island of Hawaii). The population of T. torrenticola from Molokai has a reduced chromosome number (n=4) and fixed inversions. T. abnormis and T. hirtus, the only species which exhibit differentiated sex chromosomes, may be derived from the standard sequency by paracentric inversions. T. abnormis (n=4) has a simple XY system and T. hirtus (n=3/4) has a complex XY1Y2 system. Unique sequences of bands, differences in staining intensity of puffs and bands, and an inversion form the basis for the differentiation of the various Y-chromosomes in these species.  相似文献   

11.
A taxonomic revision of Tectaria from New Caledonia is presented here based on a thorough study of herbarium specimens from New Caledonia and adjacent Pacific islands. Six species of Tectaria are presently recognized in New Caledonia. Tectaria kouniensis and T. pseudosinuata are reduced to synonyms of T. dissecta and T. sinuata, respectively. The morphological limit between T. seemannii and T. sinuata and the confused specimen citations in previous accounts are clarified. Apart from T. dissecta, the other five species, i.e. T. lifuensis, T. moorei, T. seemannii, T. sinuata and T. vieillardii, are mainly distributed in New Caledonia, with only T. seemannii and T. sinuata recently reported also from Vanuatu. A key to species, typification of accepted names and relevant synonyms, and brief comments on the relationships of species are provided.  相似文献   

12.
The genus Tribolium Desv. consists of nine species, i.e., T. utriculosum (Nees) Renv., T. ciliare (Stapf) Renv., T. echinatum (Thunb.) Desv., T. hispidum (Thunb.) Desv., T. acutiflorum (Nees) Renv., T. obliterum sensu Davidse, T. glomeratum sensu Davidse, T. uniolae (L.f.) Renv., and T. brachystachyum (Nees) Renv. The genus has a basic chromosome number of 6, and from diploid to hexaploid specimens have been examined. Precocious segregation of metaphase I bivalents were observed in four species. Multivalent formation results in unequal chromosome segregation during anaphase I, and several cells with an 11–13 chromosome distribution have been observed. The presence of univalents and anaphase I bridges in all T. brachystachyum specimens suggests a hybrid origin for the species. B-chromosomes were present in specimens from four species. The B-chromosomes are similar to the euchromosomes with the exception that they do not participate in meiosis. The B-chromosomes have a possible isochromosome origin. The cytogenetic evidence presented supports the combination of Plagiochloa and Lasiochloa into Tribolium and indicates that the genus is closely related to Urochlaena, whereas it is not closely related to Prionanthium.  相似文献   

13.
Southern African gerbils comprise 3 genera, each genus represented by morphologically- and ecologically-similar species. All species are monomorphic, with social systems varying from asocial (Desmodillus auricularis) to colonial (Tatera species). This study compares the behaviour patterns of an allopatric species, T. afra, 2 sympatric species, T. leucogaster and T. brantsii, and a species of a different genus, D. auricularis which is sympatric with T. leucogaster and T. brantsii. Interactions between males and females of the same species were staged and quantified in terms of the frequencies of each of 23 behavioural acts. D. auricularis performed 2 acts, namely “sidle” and “fight” which have not been identified in Gerbillurus or Tatera interactions. Sequences of behaviour were similar in all species, and involved females moving away from males, which followed, sniffed the anogenital region and attempted to mount the females. Females responded by presenting, if receptive, or agonistic behaviour such as aggressive or upright postures. Exploration of the terrarium accounted for a large proportion of the behaviour during the 20 min encounter, and watching the opponent also occurred frequently. Discriminant function analysis successfully separated all 4 species on the basis of behaviour frequencies. Individuals were assigned to the correct species with an accuracy of 80%, indicating that each species exhibits species-specific patterns of behaviour. D. auricularis displayed more agonistic and sexual behaviour and less huddling behaviour than any of the Tatera species. The sympatric species-pair, T. leucogaster and T. brantsii, exhibited more significant difference in behaviour than either of the allopatric species-pairs, T. afra and T. brantsii, and T. afra and T. leucogaster. Divergence in behaviour patterns has occurred in allopatric species, but divergence is more marked in species which are sympatric. It is not known whether divergence between T. leucogaster and T. brantsii occurred during a period of allopatry, or whether divergence has occurred due to selection against hybrids in sympatry.  相似文献   

14.
Numerous individuals of the poorly known species Lecithostaphylus retroflexus (Zoogonidae) and Tergestia acanthocephala (Fellodistomidae) have been recovered from the teleost fish Belone belone gracilis from off the Scandola Nature Reserve, Western Mediterranean. They are redescribed, incorporating previously undescribed features: for L. retroflexus, a post-oral ring, a bipartite seminal vesicle, the shape of the excretory vesicle, the subterminal excretory pore and the flask-shaped gland-cells associated with the distinctly pedunculate ventral sucker; and for T. acanthocephala, the intestinal bifurcation in the forebody, necessitating its return to the genus Tergestia from Theledera. Additionally, T. acanthocephala is compared with T. laticollis from various species of Trachurus from the same geographical area.  相似文献   

15.
The six species of the sectionFoenum-graecum ofTrigonella have the same chromosome number, 2n = 16.T. gladiata andT. cariensis have fairly symmetrical karyotypes, while those ofT. foenum-graecum, T. berythea, T. macrorrhyncha andT. cassia are asymmetrical. C-bands are present in all six species but the number of bands and their positive vary considerably among the species. The karyotype evidence suggests that none of the available species of theFoenum-graecum section can be considered as the wild progenitor of fenugreek.  相似文献   

16.
The ultrastructural features of oospore wall ornamentation in the genus Tolypella were examined using scanning electron microscopy (SEM). The taxonomic relationships among several species were discussed on the basis of oospore ultrastructure and measurements. In the case of T. glomerata and T. nidifica, our results support the status of separate species. Close relationships and transitional forms may exist between T. nidifica and T. normaniana, and not only in oospore wall ornamentation. Oospores of T. hispanica exhibited the same distinct type of reticulate oospore wall as previously reported, but our results do not support the recognition of T. hispanica as a separate species. Ultrastructure of the oospore walls of T. prolifera and T. intricata was almost identical, suggesting that these species are closely related. We therefore reject previous suggestions that morphological characteristics of oospores as observed in SEM are sufficient for identification of individual species. Although significant differences were found among oospores in individual species of Tolypella, large variation among populations, and among individuals belonging to the same population, caused substantial overlap among species.  相似文献   

17.
The small phytoplankton genus Triparma belongs to the class Bolidophyceae and contains two distinct forms: silicified species and naked flagellated species (formerly Bolidomonas). Recent studies showed that four silicified species/strains (Triparma laevis f. inornata, T. laevis f. longispina, T. strigata, and T. aff. verrucosa) belong to a single clade that is paraphyletic, because it also contains an unclassified flagellated strain, and is sister to a flagellated species, T. eleuthera. In this study, we isolated and characterized two new strains of silicified species to test the phylogenetic unity of silicified bolidophytes. The isolates were identified as T. retinervis strains because they possessed fine areolation on the cell wall. 18S rDNA and rbcL phylogenetic analyses demonstrated that T. retinervis formed a new silicified clade that is sister to the flagellated species T. pacifica. This reveals that there are at least two distinct clades including both silicified and flagellated Triparma species.  相似文献   

18.
The purpose of this study was to study and redescribe Terranova galeocerdonis (Thwaite, 1927) from Carcharias taurus off Argentina. Its fourth larval stage was described, measured and illustrated for the first time. The host and geographical range of this species is extended into the southwestern Atlantic Ocean. When the present material was compared with T. rochalimai (Pereira, 1935) and T. ginglymostomae Olsen, 1952, it was considered that both morphological and morphometrical differences between the three species did not justify differentiation at the specific level. As a result, T. rochalimai and T. ginglymostomae are considered to be junior synonyms of T. galeocerdonis.  相似文献   

19.
The aim of this study was to identify the habitat requirements and host specificity of three root parasites in the genus Thesium (T. linophyllon, T. bavarum and T. ebracteatum). We conducted a vegetation survey and tested whether some plant species occur significantly more often in plots with Thesium spp. than expected, thereby representing potential hosts of the parasites. To test if the potential hosts are the species to which Thesium is physically attached, we also conducted an excavating and sowing experiment. We found a positive association with surrounding species for T. linophyllon, but not for the other two species. The number of haustoria of T. linophyllon attached to roots of host species was significantly affected by the number of roots of the surrounding species and by their identity (species, family and plant group). Thesium was, however, attached to 94% of all species occurring in the plots. We suggest that Thesium spp. do not specifically select hosts, but rather occur in microhabitats with specific conditions. This conclusion is also supported by the fact that there were differences in the microhabitats with and without Thesium and that germination of Thesium in the sowing experiment was higher in pots without any host. © 2010 The Linnean Society of London, Botanical Journal of the Linnean Society, 2010, 164 , 394–408.  相似文献   

20.
We used ITS and trnL sequence data, analyzed separately and combined by MP, to explore species relationships and concepts in Trema (Celtidaceae), a pantropical genus of pioneer trees. Whether Trema is monophyletic or includes Parasponia is still unresolved. Three clades within Trema received moderate to high support, one from the New World and two from the Old World, but their relationships were not resolved. In the New World, specimens of T. micrantha formed two groups consistent with endocarp morphology. Group I, with smaller brown endocarps, is a highly supported clade sister to T. lamarckiana. Group II, with larger black endocarps, is poorly resolved with several subclades, including the highly supported T. integerrima clade. Both Old World clades contain Asian and African species, with three or more species in each region. Trema orientalis is not monophyletic: specimens from Africa formed a highly supported clade sister to T. africana, while those from Asia were sister to T. aspera from Australia.  相似文献   

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