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International audience; The carob tree (Ceratonia siliqua L.) is an important component in semi-arid Mediterranean ecosystems, particularly in Morocco where it plays a considerable socioeconomic role. This species is widely used in the reforestation programmes and in the rehabilitation of degraded soils serving both environmental and socioeconomic objectives. In spite of these assets, this species is suffering the particular climatic conditions, rare and irregular rains, long hot and dry summers, generally, leading to desertification processes. To withstand these contrasting conditions, selected arbuscular mycorrhizal fungi (AMF) were tested for their contribution to the growth, nutrient uptake and photosynthesis improvement of the carob tree C. siliqua under nursery conditions. The objective of this study was, to evaluate the effects of some arbuscular mycorrhizal fungi complexes isolated in different Mediterranean ecosystems compared to single-species isolates selected using morphological tools on the growth, mineral nutrition, and chlorophyll content of C. siliqua seedlings. The results indicate that all the used AMF inocula stimulated significantly the height of C. siliqua seedlings after eight months under nursery conditions. An increase in plant height between 33% and 70% compared to a control without inoculation was recorded. Similarly, the aerial dry weight recorded an increase of 62% to 124% comparing inoculated and non-inoculated seedlings. The root dry weight has shown an increase rate of 24% to 86% compared to the control. The analysis of mineral contents in plant tissues, showed a highly significant increase in P. N. K. Ca and Mg levels of the aerial parts compared to the control. A significant increase in chlorophyll contents was noticed when inoculated seedlings were compared to non-inoculated ones. This study had confirmed the importance of AMF improving the growth of C. siliqua seedlings; the AMF complexes remain to have the important growth and mineral nutrition responses. However some single-species have shown similar magnitude to the complexes for all analysed parameters. A large biofertilizer potential of the single-species isolates in the inoculation of C. siliqua is demonstrated for the first time.

Bacterial extracellular vesicles (EVs) are nanoscale lipid-enclosed packages that are released by bacteria cells and shuttle various biomolecules between bacteria or host cells. They are implicated in playing several important roles, from infectious disease progression to maintaining proper gut health, however the tools available to characterise and classify them are limited and impractical for many applications. Surface-enhanced Raman Spectroscopy (SERS) provides a promising means of rapidly fingerprinting bacterial EVs in a label-free manner by taking advantage of plasmonic resonances that occur on nanopatterned surfaces, effectively amplifying the inelastic scattering of incident light. In this study, we demonstrate that by applying machine learning algorithms to bacterial EV SERS spectra, EVs from cultures of the same bacterial species Escherichia coli can be classified by strain, culture conditions, and purification method. While these EVs are highly purified and homogeneous compared to complex samples, the ability to classify them from a single species demonstrates the incredible power of SERS when combined with machine learning, and the importance of considering these parameters in future applications. We anticipate that these findings will play a crucial role in developing the laboratory and clinical utility of bacterial EVs, such as the label-free, noninvasive, and rapid diagnosis of infections without the need to culture samples from blood, urine, or other fluids.

Environmental DNA (eDNA) has been utilized for the detection of target species, and its application in biomass estimation has great potential. However, there are several factors that may hinder this application, such as species-specific eDNA emission, interspecific interactions, and the effect of feeding. In this experiment, we quantified eDNA emission in the striped jack Pseudocaranx dentex and the jack mackerel Trachurus japonicus in single- and mixed-species tanks for 10 days over a 12-day experimental period. eDNA concentrations of both of these species peaked on the first day of the experiment and later stabilized. The linear mixed-effects model revealed that the temporal factor, being highest immediately after their introduction into experimental tanks, had significant effects on eDNA concentration, whereas fish species and feeding factors did not. Rearing conditions of mixed or single species were not significant either. Taken together with previous studies, eDNA emission may be equal in fishes that have similar morphology and behavior, and their interspecific interaction may be negligible for eDNA detection.

In the present work, a series of tests were performed to examine the effect of previously captured adults in floor traps, on the captures of Τrogoderma granarium Everts and T. variabile Ballion, in single species releases. In a first series of tests, a single trap with kairomone oil and dead adults of single or both species was placed in a plastic container, which was used as the release arena. Subsequently, adults of both species were separately released in the arena, and the adult capture was recorded 24 h later. In a second series of trials, two traps were placed in the same arena, containing different numbers of prior seeded adults, and adult capture was similarly recorded. For T. granarium, in all cases, more adults were found inside the trap than under the trap or on the trap walls. In contrast, for T. variabile, most adults were recorded on the trap walls. In general, T. variabile had a stronger response to the traps than T. granarium. This work illustrates that previous captures of either species do not negatively affect captures of new live adults and may tend to enhance captures in some cases. This has important implications for the use of traps for the biosureveillance of these two important dermestid species.

The epithet “alpina” has been recurrently used in the genus Deschampsia to name plants located in northern regions of Europe, Asia and North America, as a species (Deschampsia alpina (L.) Roem. & Schult.), but also in infraspecific categories (Deschampsia cespitosa subsp. alpina Tzvel. and Deschampsia cespitosa var. alpina Schur.). The morphological and molecular available evidence suggests the existence of a single species, Deschampsia cespitosa (L.) P. Beauv., in which individuals belonging to the same morphological gradient have received different names in different taxonomic categories throughout its wide distribution range. An evaluation of the available names indicates that all uses of the epithet “alpina” are illegitimate. A new combination is proposed at the infraspecific level as Deschampsia cespitosa subsp. neoalpina Chiapella, Xue & Greimler.

Goal. Establish the best perennial legumes when grown in single-species and compatible fodder agrocenoses with stokolos boneless and the effectiveness of the use of nitrogen-fixing and phosphorus-mobilizing bacterial preparations, as well as liming. Methods. General scientific − hypotheses, inductions and deductions, analogies, generalizations and special − field, laboratory, mathematical and statistical, computational and comparative. Results. Based on the generalization of literature sources, it is proved that the creation of sown grasslands, with high content of perennial legumes on meadows and arable lands, which are derived from intensive cultivation is one of the most promising areas of organic onion growing. Productivity of single-species crops of perennial legumes and their mixtures with boneless stalk on average for five years after the yield of 1 ha of dry mass in the version without fertilizers ranged from 5.12 to 8.38 tons, which is 1.7−2.5 times more in comparison with a grassy grass stand which is formed from one-species crops of a stokolos of a boneless. The highest productivity and level of symbiotic nitrogen accumulation (191−266 kg / ha) were provided by agrocenoses with the participation of alfalfa, and the lowest - meadow clover. The efficiency of soil liming during sowing of grasses and application of inoculation of seeds of perennial legumes with nitrogen-fixing and phosphorus-mobilizing preparations is given. Changes in the chemical composition of feed under the influence of the studied factors are also shown. Conclusions. Different types of perennial legumes and their mixtures with boneless stalk without fertilizers provide productivity in the range of 5.12−8.38 t / ha of dry weight, which is 1.7−2.5 times more than the grass cover, which is formed from single-species sowing of stokolos bezzostoy. Inoculation of perennial legume seeds with nitrogen-fixing and phosphorus-releasing microbiological preparations increases the productivity of perennial legumes and their mixtures with cereals by 2−6%, and soil liming before sowing – by 3−11%. The greatest effect is provided by the combined use of these bacterial drugs. Alfalfa sowing responds best to their use and liming.

H2S and H2O2 are two redox regulating molecules that play important roles in many physiological and pathological processes. While each of them has distinct biosynthetic pathways and signaling mechanisms, the crosstalk between these two species is also known to cause critical biological responses such as protein S-persulfidation. So far, many chemical tools for the studies of H2S and H2O2 have been developed, such as the donors and sensors for H2S and H2O2. However, these tools are normally targeting single species (e.g., only H2S or only H2O2). As such, the crosstalk and synergetic effects between H2S and H2O2 have hardly been studied with those tools. In this work, we report a unique H2S/H2O2 dual donor system by employing 1-thio-β-d-glucose and glucose oxidase (GOx) as the substrates. This enzymatic system can simultaneously produce H2S and H2O2 in a slow and controllable fashion, without generating any bio-unfriendly byproducts. This system was demonstrated to cause efficient S-persulfidation on proteins. In addition, we expanded the system to thiolactose and thioglucose-disulfide; therefore, additional factors (β-galactosidase and cellular reductants) could be introduced to further control the release of H2S/H2O2. This dual release system should be useful for future research on H2S and H2O2.

Introduction Lower respiratory tract secretions (LRTS) like sputum and tracheal aspirates are frequently sent to the microbiology laboratory from patients with various respiratory pathologies. Improper collection techniques can lead to false-positive results, resulting in improper therapy. Aim of the study To determine the percentage of contaminated samples sent to the microbiology laboratory, to establish the prevalence of Candida spp. in non-contaminated samples and therefore, the presence of Candida spp. originating in lower respiratory tract infections. Material and Methods A 10-year data survey was conducted to assess the differences in Candida prevalence from contaminated versus non-contaminated samples, assessed and categorised by Bartlett grading system, and to emphasise the importance of quality control for potentially contaminated samples. The data were analysed according to gender, age, referring departments, and the species of Candida. For the statistical analysis, Kruskal-Wallis and Fisher tests were used, and the alpha value was set for 0.5. Results The prevalence of Candida spp. in all analysed samples was 31.60%. After excluding the contaminated samples, the actual prevalence was 27.66%. Of all sputum samples, 31.6% were contaminated. Patients aged more than 40 years old were more prone to provide contaminated sputum samples. C. albicans is more prevalent in non-contaminated sputum samples. In both sputum and tracheal aspirates, the chances of identifying a single species are higher than the chances of identifying multiple species. Conclusions The study emphasises the importance of assessing the quality of sputum samples because of the high number of improperly collected samples sent to the microbiology laboratory.

A swarm is a group of a single species in which the members interact with one another and with the immediate environment without a principle for control or the emergence of a global intriguing behavior. Swarm-based metaheuristics, including nature-inspired populace-based methods, have been developed to aid the creation of quick, robust, and low-cost solutions for complex problems. Swarm intelligence was proposed as a computational modeling of swarms and has been successfully applied to numerous optimization tasks since its introduction. A correlation with the fundamental Particle Swarm Optimization (PSO) and PSO modifications demonstrates that hybrid swarm optimization outperforms existing strategies. The downside of hybrid swarm optimization is that it frequently tends to arrive at suboptimal solutions. As such, efforts are being made into combining HSO and other algorithms to arrive at better quality solutions

Clarinets are made with a variety of materials, e.g., plastic, graphite, porcelain, or even metal. However, the most commonly used material to make clarinets is wood. Today, African granadilla or African blackwood (Dalbergia melanoxylon) is the most popular and most widely used species by leading international companies in terms of clarinet production, because of its high density, color, fine texture, and exceptional durability. This species is also used to manufacture flutes, oboes, and bagpipes, making African blackwood one of the most valuable tree species in the world. However, the focus on the usage of a single species puts considerable pressure on a rare and endangered wood species. Therefore, this work aims to identify viable alternatives to African blackwood in terms of manufacturing clarinets as well as providing a similar combination of instrument characteristics that musicians and companies believe contribute to the value of the instrument, e.g., acoustics, aesthetics, and price.

The paper aims to provide a comprehensive overview of karyological and morphological variability of the Tanacetum corymbosum group in Slovakia. We estimated DNA ploidy level and relative DNA content of 530 individuals (45 populations) using DAPI flow cytometry. The morphological variation was studied by univariate as well as multivariate morphometric based on 10 morphological characters of 351 individuals (39 populations). In addition, two characters were measured on 120 achenes (six populations). Flow cytometry analyses confirmed two predominant cytotypes within T. corymbosum group in Slovakia: diploids corresponding to T. clusii and tetraploids corresponding to T. corymbosum. Further, we recorded rare occurrence (1.3% of the dataset) of minority cytotypes – presumable triploids and pentaploids, probably originating from fusion of reduced and unreduced gamete in single species populations. One triploid plant found at the only one locality with common occurrence of T. clusii and T. corymbosum is most probably of hybrid origin. Morphological analyses showed that T. clusii and T. corymbosum could not be clearly distinguished by either of the studied characters but by combining all studied quantitative characters of stem, leaves, and corymbs, it was possible to correctly classify more than 91% of the plants. Number and size of stem leaves as well as capitula, and coloration of the margin of the involucral bracts were identified as the most useful for their determination. Based on revealed karyological and morphological differentiation of T. clusii and T. corymbosum, we favour to recognize them as two separate species rather than subspecies. A key for identifying native Tanacetum species in Slovakia is presented.

In Ethiopia, most of the studies on mammals have focused on single species and protected areas. This survey investigated the impacts of habitats and seasons on the medium and large-sized mammals’ diversity and distribution in a human-dominated landscape. This survey was conducted using 36 systematically distributed transect lines within stratified habitat types. A total of 685 records belonging to 21 species, six orders, and 13 families were identified, including globally vulnerable Panthera leo, Panthera pardus, and Hippopotamus amphibious. Overall, Papio anubis and Chlorocebus aethiops were the dominant species recorded in the area. Except for three species, all species encountered in the three habitats are subsets of the species recorded in the grassland. The species record frequency was highest in the forest. The dry season characterized by a higher frequency of records but by lower species richness than the wet season. In general, the study area is potential for mammalian species conservation in Ethiopia.

Although dolphins are mostly known to form single species groups of varying size, occasionally they aggregate in mixed-species groups. The presence of mixed-species delphinid groups along the Peruvian coast is unknown. Herein, we report the presence of a single pantropical spotted dolphin (Stenella attenuata) within large groups of the common dolphin (Delphinus delphis) at Los Organos in the northern coast of Peru. Sightings occurred on October 10th, 2016, January 7th, 2018 and September 21st, 2019. In one sighting the mixed group was feeding, while during the other two sightings the group was travelling. These records add new evidence about mixed-species delphinid groups in coastal waters of Peru.

A.E. Morales et al. (2021. Can. J. Zool. 99(5): 415–422) provided no new evidence to alter the conclusions of C.L. Lausen et al. (2019. Can. J. Zool. 97(3): 267–279). We present background information, relevant comparisons, and clarification of analyses to further strengthen our conclusions. The genesis of the original “evotis–keenii” study in British Columbia (Canada) was to differentiate Myotis keenii (Merriam, 1895) (Keen’s myotis), with one of the smallest North American bat distributions, from sympatric Myotis evotis (H. Allen, 1864) (long-eared myotis), using something other than the suggested post-mortem skull size comparison, but no differentiating trait could be found, leading to the molecular genetics examination of C.L. Lausen et al. (2019). We present cumulative data that rejects the 1979 hypothesis of M. keenii as a distinct species. A.E. Morales et al. (2021) inaccurately portray C.L. Lausen et al.’s (2019) question and results; present inaccurate morphological and outdated distribution data; overstate the impact of homoplasy without supporting evidence; and misinterpret evidence of population structure.

Genetic exchange and hybridization appear common among the western long-eared bats from North America. Multiple sources of evidence indicate that lineages within this group are evolving independently, despite genetic exchange. However, evidence of gene flow raises questions about the species-level status of some lineages. C.L. Lausen et al. (2019. Can. J. Zool. 97(3): 267–279) proposed that Myotis evotis (H. Allen, 1864) (long-eared myotis) and Myotis keenii (Merriam, 1895) (Keen’s myotis) are one species, not two. This conclusion is based on analyses of cytochrome b and microsatellite data suggesting gene flow between these taxa. Microsatellites are not reliable markers for identifying species because homoplasy can be a major confounding factor, which appears to be true in this case. We reanalyzed the dataset of C.L. Lausen et al. (2019) and show that it is not reliable to distinguish between gene flow or homoplasy, and that these data do not support the conclusion that M. evotis and M. keenii represent a single species. Previous morphological and genomic studies indicate that these are separate species despite previous genetic exchange between them. Failing to recognize that gene flow can occur between independently evolving lineages is counterproductive for conservation because it can lead to neglect of important independent lineages, and likewise failing to use proper tools to delimit species is counterproductive to efforts to quantify biodiversity and design conservation strategies.

Phototrophic biofilms, also known as periphyton, are microbial freshwater communities that drive crucial ecological processes in streams and lakes. Gaining a deep mechanistic understanding of the biological processes occurring in natural periphyton remains challenging due to the high complexity and variability of such communities. To address this challenge, we rationally developed a workflow to construct a synthetic community by co-culturing 26 phototrophic species (i.e., diatoms, green algae, and cyanobacteria) that were inoculated in a successional sequence to create a periphytic biofilm on glass slides. We show that this community is diverse, stable, and highly reproducible in terms of microbial composition, function, and 3D spatial structure of the biofilm. We also demonstrate the ability to monitor microbial dynamics at the single species level during periphyton development and how their abundances are impacted by stressors such as increased temperature and a herbicide, singly and in combination. Overall, such a synthetic periphyton, grown under controlled conditions, can be used as a model system for theory testing through targeted manipulation.

A taxonomic reappraisal of four marine littoral Phucobius Sharp species along the western Pacific Ocean including the South China Sea is presented based on morphological and molecular characters (COI and 28S). Specimens of the four species, each having its own distinct geographic distribution, are extremely similar to each other including the structures of the median lobe of the aedeagus, and may be regarded as conspecific. Also, the molecular analyses support the validity of P. pectoralis with three synonymies based on morphological characters. Genetic divergence of COI using uncorrected p-distance among all individuals of Phucobius species ranged from 0.11% to 3.21%. Three distinct geographical clusters (Russia, Korea and Japan, and Vietnam) are found in the NJ and PA trees and we treat all of them as a single species. Three new synonyms are proposed for Phucobius pectoralis (Boheman): P. simulator Sharp syn. nov., P. tricolor Bernhauer syn. nov., and P. densipennis Bernhauer syn. nov. Phucobius pectoralis is redescribed with illustrations of diagnostic characters. Also, the intraspecific variation among the populations of P. pectoralis is briefly discussed.

In this paper we investigate bifurcation phenomena in a single-species reaction-diffusion model with spatiotemporal delay under the conditions of the weak and strong kernel functions. We have found that when the weak kernel function is introduced there is Hopf bifurcation but no Turing bifurcation and wave bifurcation to occur, but when the strong kernel function is introduced there exist Hopf bifurcation and wave bifurcation but no Turing bifurcation to occur. Especially, taking the inverse of the average time delay as a bifurcation parameter, we investigate influences of the time delay on the formation of spatiotemporal patterns through the numerical method. Some spatiotemporal patterns induced by Hopf bifurcation and wave bifurcation are respectively shown to illustrate the mechanism of the complexity of spatiotemporal dynamics.

Biological control in the open field often involves simultaneous infestations of different pest species. In brassica crops, aphids and diamondback moth are major pest species worldwide. The aphidop...

The red seaweed Chondracanthus chamissoi shows high morphological variability. Initially, three species were identified based on the width of the main axis of their blades. Later, all of them were included in a single species with two morphological groups. Recently, quantitative studies demonstrated the existence of two forms in C. chamissoi: f. lessonii and f. chauvinii. It was also shown that these two forms occur in sympatry, growing side by side. These forms were not associated with either a life cycle phase or the sex of the blades. This study aimed to determine whether the two forms could represent different species. We evaluated the forms' taxonomic position using COI and rbcL markers, including samples from three localities in southern Chile. All specimens shared a single rbcL haplotype, whereas the two COI haplotypes differed by four base pairs and were present in blades of both forms and life cycle phases. The two morphological types correspond to intraspecific forms. This species is of commercial importance, and its main market is aimed at human consumption with a marked preference for f. lessonii.

Common marmosets (Callithrix jacchus) are small non-human primates that genetically lack cytochrome P450 2C9 (CYP2C9). Polymorphic marmoset CYP2C19 compensates by mediating oxidations of typical hu...

The moss cover of forests in an 50×36 km area around the Middle-Ural Copper Smelter was analyzed after almost complete reduction of its emissions. It has been shown that the moss communities in the low and high pollution zones differ significantly in composition, number and frequency of species, but are characterized by a similar cover of ground mosses. The frequency of most species in the high pollution zones, compared to the low pollution zones, was decreased. A significant increase of the frequency in the pollution gradient was found for Pohlia nutans only. Species loss was expressed more strongly on the mesoscale (species richness within a community) than on the macroscale (the total number of species in a pollution zone). The elimination of species under increasing pollution was revealed for species with a low (up to 40%) initial frequency. Despite of the almost complete cessation of emissions from the smelter, the moss cover in the high pollution zones remains severely damaged and is formed by a single species (Pohlia nutans) over a significant area. However, localities with high species richness and high similarity of composition with the background communities occur even under high pollution conditions. The presence of such localities, in combination with a considerable time lag before the extinction of species from the study area as a whole, may have major significance for recolonization of degraded areas after emission reduction.

The results emphasise the significance of further studies in the Dir Lower to get well understanding of the helminth parasites with ecological relations of their hosts. Twenty-seven specimens of Bufo stomaticus (Lutken, 1864) (Anura: Bufonidae) were collected in the Dir Lower, Khyber Pakhtunkhwa province of Pakistan in the period from April to August 2016, and examined for helminths (endoparasites) parasites. Twelve (44.44%) specimens were infected by two types of helminths parasites. Total of forty-one helminths parasites were collected, among them six were identified Cestode and the remaining thirty-five were nematodes. The dominant parasites were nematodes (Cosmocerca sp. with 56.09% followed by Cosmocercoides sp. with 29.26%). But the Cestodes were found with single species (Nematotania dispar with 14.63%). Female toads showed higher parasite diversity than male toads.

Ectatosticta spiders from the Qinghai-Tibet Plateau were studied. Multilocus molecular and morphological data identified 16 putative species, including seven new species: Ectatosticta wenshu Lin & S. Li sp. nov. , Ectatosticta baima Lin & S. Li sp. nov. , Ectatosticta helii Lin & S. Li sp. nov. , Ectatosticta shaseng Lin & S. Li sp. nov. , Ectatosticta puxian Lin & S. Li sp. nov. , Ectatosticta qingshi Lin & S. Li sp. nov. , and Ectatosticta baixiang Lin & S. Li sp. nov. This increase in the number of Ectatosticta species from a single species in 2008 to 16 in the current study highlights the Linnean shortfall in China. The previously known distribution of Ectatosticta spiders was from one locality in Shaanxi and is now expanded to the east and south of the Qinghai-Tibet Plateau.

We present a periodic nonlinear scalar delay differential equation model for a population with short reproduction period. By transforming the equation to a discrete dynamical system, we reduce the infinite dimensional problem to one dimension. We determine the basic reproduction number not merely as the spectral radius of an operator, but as an explicit formula and show that is serves as a threshold parameter for the stability of the trivial equilibrium and for permanence.

Contains fulltext : 230049.pdf (Publisher’s version ) (Closed access) Comparative neuroscience is entering the era of big data. New high-throughput methods and data-sharing initiatives have resulted in the availability of large, digital data sets containing many types of data from ever more species. Here, we present a framework for exploiting the new possibilities offered. The multimodality of the data allows vertical translations, which are comparisons of different aspects of brain organization within a single species and across scales. Horizontal translations compare particular aspects of brain organization across species, often by building abstract feature spaces. Combining vertical and horizontal translations allows for more sophisticated comparisons, including relating principles of brain organization across species by contrasting horizontal translations, and for making formal predictions of unobtainable data based on observed results in a model species. 18 p.

We analyze a reaction-diffusion system modeling the competition of multiple phytoplankton species which are limited only by light. While the dynamics of a single species has been well studied, the dynamics of the two-species model has only begun to be understood with the recent establishment of a comparison principle. In this paper, we show that the competition of \begin{document}$ N $\end{document} similar phytoplankton species, for any number \begin{document}$ N $\end{document} , generically leads to competitive exclusion. The main tool is the theory of a normalized principal bundle for linear parabolic equations.

Choristoneura Fumiferana is perilous defoliators of forest lands in North America and many countries in Europe. In this study, we consider mathematical models in ecology, epidemiology and bifurcation studies; the spruce budworm model and the population model with harvesting. The study is designed based on bifurcation analysis. In particular, the results support population thresholds necessary for survival in certain cases. In a series of numerical examples, the outcomes are presented graphically to compare with bifurcation results.

In this paper, we derive and analyse mean-field models for the dynamics of groups of individuals undergoing a random walk. The random motion of individuals is only influenced by the perceived densities of the different groups present as well as the available space. All individuals have the tendency to stay within their own group and avoid the others. These interactions lead to the formation of aggregates in case of a single species and to segregation in the case of multiple species. We derive two different mean-field models, which are based on these interactions and weigh local and non-local effects differently. We discuss existence and stability properties of solutions for both models and illustrate the rich dynamics with numerical simulations.

A taxonomic study on the flora of Dohar upazila (sub-district) under Dhaka district has been conducted that results in occurrence of 204 angiosperm taxa under 165 genera and 68 families. Magnoliopsida is represented by 158 taxa distributed in 129 genera and 53 families. In contrast, Liliopsida is constituted by 46 taxa under 36 genera and 15 families. Asteraceae appears to be the largest family in Magnoliopsida consisting of 16 species, whereas Poaceae is the largest family with 16 species in Liliopsida. In Magnoliopsida, 23 families are represented by a single species, while in Liliopsida, 7 families are symbolized by a single species. Vegetation analysis shows that herbs are represented by 133 taxa, shrubs by 23 and trees by 48 taxa. Dichotomous bracketed keys to the families, genera, species and varieties are provided for easy identification of the taxa. Each taxon is supplemented by updated nomenclature, habit and representative specimen. Bangladesh J. Plant Taxon. 27(2): 293-322, 2020 (December)

Background Codon usage is an important determinant of gene expression levels that can help us understand codon biology, evolution and mRNA translation of species. The majority of previous codon usage studies have focused on single species analysis, although few studies have focused on the species within the same genus. In this study, we proposed a multispecies codon usage analysis workflow to reveal the genetic features and correlation in citrus. Results Our codon usage analysis workflow was based on the GC content, GC plot, and relative synonymous codon usage value of each codon in 8 citrus species. This approach allows for the comparison of codon usage bias of different citrus species. Next, we performed cluster analysis and obtained an overview of the relationship in citrus. However, traditional methods cannot conduct quantitative analysis of the correlation. To further estimate the correlation among the citrus species, we used the frequency profile to construct feature vectors of each species. The Pearson correlation coefficient was used to quantitatively analyze the distance among the citrus species. This result was consistent with the cluster analysis. Conclusions Our findings showed that the citrus species are conserved at the genetic level and demonstrated the existing genetic evolutionary relationship in citrus. This work provides new insights into codon biology and the evolution of citrus and other plant species.