Levels Of Intraspecific Variation Research Articles

Historical biogeography of the Saharan horned viper enlightens past dynamics of hyperarid desert habitats

Hyperarid habitats comprise the most dominant and harsh portion of the Sahara Desert, yet how local biotas have responded to paleoclimatic shifts and landscape heterogeneity remains unclear. Here, we assess the historical biogeography of Cerastes cerastes, a conspicuous but poorly known vertebrate inhabiting the hyperarid Sahara, to understand the links between intermittent and stable climatic suitability and patterns of genetic diversity and differentiation in these extreme environments. We combine phylogeographic and ecological modelling tools using a comprehensive species dataset, which includes DNA samples (n = 62) and occurrence records (n = 557) covering most of its range. We show that paleoclimatic oscillations were major evolutionary and biogeographic drivers in C. cerastes, which exhibits different levels of intra-specific diversity and allopatric lineage structuration across the desert. High lineage richness in the north-western Sahara contrasts with an overall lack of genetic diversity throughout the central and eastern Sahara. Climatic refugia along the desert's periphery and around mountain patches harbour single endemic lineages, stressing the links between stable climatic conditions and population isolation and divergence. Increasing climatic suitability during historical arid phases prompted widespread connectivity across the desert. This study lays the groundwork for better understanding the historical dynamics of the hyperarid Sahara.

A new combination and synonym in Bupleurum (Apiaceae, Apioideae), based on morphological, molecular and cytological evidence.

Specimen examinations and field observations revealed that Bupleurumsmithiivar.parvifolium was distinctly different from B.smithiivar.smithii in umbel, leaf, and fruit morphology, but was very similar to B.commelynoideumvar.flaviflorum. Based on these morphological evidences, the present study re-examined the taxonomic status of these taxa through morphological, cytological, and phylogenetic analyses. The results showed distinguishable features in the width of middle leaves and bracteoles of B.smithiivar.parvifolium compared to B.smithiivar.smithii. Morphological variation between B.smithiivar.parvifolium and B.commelynoideumvar.flaviflorum was continuous and overlapping. Notably, the chromosome number of B.smithiivar.parvifolium was 2n = 14 (x = 7), consistent with B.commelynoideumvar.flaviflorum, whereas B.smithiivar.smithii was 2n = 64 (x = 8). Additionally, phylogenetic analyses revealed B.commelynoideumvar.flaviflorum nested within B.smithiivar.parvifolium, and that both were distant from the B.smithiivar.smithii and B.commelynoideumvar.commelynoideum. Based on the evidence above, the differences between B.smithiivar.parvifolium and B.smithiivar.smithii extend beyond the level of intraspecific variation, and B.commelynoideumvar.flaviflorum is considered to be identical with B.smithiivar.parvifolium. Hence. A new combination and status, B.parvifolium (Shan & Y.Li) Q.R.Liu & L.H.Wang, comb. et stat. nov., is proposed. Furthermore, B.commelynoideumvar.flaviflorum should be treated as a synonym of B.parvifolium.

Phylogeography of Limia vittata (Cyprinodontiformes: Poeciliidae): geographical distribution of mitochondrial haplotypes is comparable to other Cuban poeciliids

Abstract The genus Limia is endemic to the Greater Antilles with a single species in Cuba, Limia vittata, widespread in lowland ecosystems. The limited data available regarding its population structure suggest that its levels of intraspecific divergence are lower compared to other Cuban poeciliids. Furthermore, little is known about the dispersal pathways and demographic changes experienced by present-day populations. By analysing two mitochondrial markers and testing scenarios of dispersal and vicariance, we provide insights into the evolutionary history of L. vittata. Here, we show that this species is formed by three genetically differentiated and geographically delimited groups of populations. We also found moderate intraspecific divergence and a mtDNA pattern of high haplotype diversity and low nucleotide diversity which is consistent with a rapid demographic expansion. Our Bayesian analysis recovered dispersal from eastern to western Cuba as the most likely scenario explaining the current distribution of this species. Limia vittata exhibited a distinct regional distribution of haplogroups that corresponds to major core landmasses within Cuba, along with a signature of rapid population expansion during relatively recent palaeoclimatic changes that occurred during the formation of the archipelago. Similar phylogeographic patterns have been identified in other freshwater and terrestrial taxa on the island.

Are Appearances Deceiving? Morpho-Genetic Complexity of the Eumerus tricolor Group (Diptera: Syrphidae) in Europe, with a Focus on the Iberian Peninsula.

Eumerus Meigen, 1822 is one of the largest Syrphidae genera in the Palaearctic Region, with the highest levels of taxonomic diversity found in the Eumerus tricolor species group. Despite its high diversity, the interspecific levels of morphological variability can be low. Additionally, some species may show certain levels of intraspecific variability. Hence, species delimitation may become challenging. In this work, we assessed the diversity of the E. tricolor group in the Iberian Peninsula through an integrative analysis of nomenclature, morphology and the 5' (COI-5') and 3' (COI-3') end regions of the Cytochrome c oxidase subunit I gene. Two new species, Eumerus ancylostylus Aguado-Aranda & Ricarte sp. n. and Eumerus petrarum Aguado-Aranda, Nedeljković & Ricarte sp. n., were described, and their intra- and interspecific variations discussed. In addition, the first barcodes of Iberian members of the E. tricolor group were obtained, and the distribution ranges of all species were mapped within the study area. The systematic position of the new species is discussed based on the resulting COI-based trees. The male genitalia of Eumerus hispanicus van der Goot, 1966 and Eumerus bayardi Séguy, 1961 were studied and illustrated. A lectotype was designated for Eumerus lateralis (Zetterstedt, 1819). An updated dichotomous key for all known European species of the E. tricolor group is provided. The egg of E. petrarum sp. n. is also described.

Lower Levels of Vestibular Developmental Stability in Slow-Moving than Fast-Moving Primates

The vestibular system of the mammalian inner ear senses angular and linear velocity of the head and enables animals to maintain their balance. Vestibular anatomy has been studied extensively in order to link its structure to particular kinds of locomotion. Available evidence indicates that, in primates, slow-moving species show higher levels of vestibular variation than fast-moving taxa. We analysed intraspecific morphological variation and fluctuating asymmetry (FA) levels in the semicircular canal systems of six species of lorisiform primates: three slow-moving lorisids and three fast-moving galagids. Our results showed clear differences in levels of intraspecific variation between slow-moving and fast-moving taxa. Higher levels of variation were responsible for deviations from coplanarity for synergistic pairs of canals in slower taxa. Lorisids also presented higher levels of FA than galagids. FA is a better indicator of agility than intraspecific variation. These results suggest that in order to function efficiently in fast taxa, semicircular canal systems must develop as symmetrically as possible, and should minimise the deviation from coplanarity for synergistic pairs. Higher levels of variation and asymmetry in slow-moving taxa may be related to lower levels of stabilising selection on the vestibular system, linked to a lower demand for rapid postural changes.

Comparison of a Chilean strain of the ichthyotoxic phytoflagellate Heterosigma akashiwo (Raphidophyceae) with strains from France, Spain and New Zealand

ABSTRACT Heterosigma akashiwo is a bloom-forming planktonic flagellate that causes fish mortalities, which damages the aquaculture industry worldwide. In Chile, this species was reported for the first time in 1988 when it caused one of the most dramatic harmful algal blooms in the south of the country. At that time, an unialgal culture was set and used for a morphological characterization but, unfortunately, it was not maintained. In April 2013 a new outbreak of H. akashiwo was detected in the Maullín Estuary (41°37′S, 73°36′W), Southern Chile, causing fish mortalities in commercial salmon farms. An unialgal culture of this new Chilean population of H. akashiwo was obtained and has been maintained in the Culture Collection of Microalgae of the University of Concepción, Chile, under the code CCM-UdeC 225. The aim of this study was to compare the morphological and physiological attributes of this Chilean strain of H. akashiwo with those of strains from France, Spain and New Zealand, in order to identify eventual intraspecific variability among them. Cell size, growth parameters, pigments profiles, photosynthetic attributes and toxicity were determined for the strains, grown under identical culture conditions. The Chilean strain exhibited the highest growth and accumulated the highest proportion of the carotenoid fucoxanthin, while strains from Chile and Spain were the less light-tolerant and had similar toxicity. These results reinforce previous findings about the high level of intraspecific variability within H. akashiwo including, for the first time, a strain from South America.

Intraspecific variation in molar topography of the early Eocene stem primate Microsyops latidens (Mammalia, ?Primates)

ABSTRACT Variation in postcanine teeth is relevant to answering questions about both taxonomy and diet. In such contexts, understanding the patterns and the amounts of variation present in a single species is fundamentally important. Here we use dental topographic analysis (DTA) to study variation in functional aspects of the lower second molar (n = 51) and lower fourth premolar (n = 41) in a large, stratigraphically controlled sample of the early Eocene stem primate Microsyops latidens, which permits study of fine scale variation through time in a single species, during a period of notable climatic change. To contextualize variation in M. latidens, we used DTA to study extant euarchontan taxa, representing three orders and seven families (n = 96). Previous study of M. latidens suggested that it was highly variable in size and lower molar morphology, potentially giving rise to later species of microsyopids. However, comparison with extant taxa suggests that the dental form of M. latidens shows low levels of intraspecific variation. The dental topography of M. latidens also does not reflect the previously postulated taxonomic split. Our results suggest instead that M. latidens likely did not undergo change in dental topography consistent with a shift in either dietary adaptive niche or ecospace. Taken together, our results suggest low levels of variation in dental form and potentially diet of M. latidens, indicating that this taxon likely remained within a single adaptive zone.

Species‐specific trends and variability in plant functional traits across a latitudinal gradient in northern Alaska

AbstractQuestionsMany studies explore how plant functional traits may change as the climate warms by observing traits over environmental gradients. The amount of intraspecific variation (ITV), however, is often unknown and unaccounted for in most trait‐based studies. Our objectives are to: (a) determine if species‐level patterns across a latitudinal gradient match those of other members within the same growth form; (b) compare distributions of trait values across regions; and (c) quantify the amount of ITV within each trait relative to the amount of variation within the growth form and across taxonomic levels (family and species).LocationUtqiaġvik, Atqasuk, and Toolik Lake, Alaska.MethodsThis study examines seven plant functional traits for 12 arctic species. Traits were measured on 10 individuals of each species at each region and analyzed using one‐way ANOVA and variance partitioning via nested ANOVA.ResultsComparison of mean trait values across the three regions for each species showed considerable variability within a growth form. Within deciduous shrubs, for example, one species increased in specific leaf area (SLA) with latitude while another species decreased. Results from variance partitioning differed among functional traits. Across the three regions, plant height, leaf area, SLA, leaf thickness, and leaf dry matter content (LDMC) had relatively low amounts of intraspecific variation (ITV; <15%) while normalized difference vegetation index (NDVI) had a high amount of ITV (>50%). All traits showed significant differences across regions for at least some species.ConclusionsBecause our results showed considerable variability in levels of ITV among functional traits, we emphasize the need to investigate ITV in trait‐based studies spanning multiple regions. Levels of ITV are important in determining how different populations respond to local environmental conditions. Incorporating ITV in studies investigating vegetation change with warming will provide more robust and reliable predictions.

The first step towards a DNA barcode reference database for mayflies (Ephemeroptera) of Slovakia

Mayflies (Ephemeroptera) represent a small but diverse order of amphibiotic insects, whose larvae contribute to several essential processes in freshwater habitats, such as bioturbation and bioirrigation, decomposition, nutrient cycling, and also serve as a primary source of nutrients for numerous organisms. Due to their cosmopolitan distribution and high-quality water requirements, they are also important indicators of ecosystem health and an integral part of biomonitoring protocols. Although the Slovak mayfly fauna is well researched, studies on genetic diversity, including DNA barcoding, are still lacking. The absence of the comprehensive DNA barcode reference libraries from various biogeographical regions and the presence of so-called cryptic lineages may prevent further efficient use and application of new approaches to aquatic ecosystem biomonitoring (Biomonitoring 2.0) based on eDNA analyses. Therefore, in the initial stage of our research, we bring the first insight into the genetic diversity of mayflies (based on mtDNA COI-5P barcoding fragment) from 47 localities of Slovakia mostly situated in the biogeographically significant Western Carpathians' territory. A total of 403 sequences of 42 morphologically determined species were added to the BOLD (Barcode of Life Data System) database, representing more than 1/3 of the mayfly fauna of Slovakia and covering 10 of 16 families. Sequences of these species were finally assigned to 62 BINs (Barcode Index Numbers) in BOLD (Fig. 1), whereby sequences of 12 species were divided into more than one BIN, indicating the presence of cryptic lineages. The largest number of BINs was represented by widely distributed species such as Baetis rhodani Pictet, 1843-1845 (6 BINs), Habroleptoides confusa Sartori & Jacob, 1986 (4 BINs) and Ecdyonurus venosus (Fabricius, 1775) (3 BINs). The sequences of the remaining nine species were split into two BINs. Maximum intraspecific variability (calculated by K2P) of some representatives was surprisingly high [e.g., E. venosus – 27.1 %; Baetis muticus (Linneaus, 1758) – 23.6 %; Caenis luctuosa (Burmeister, 1839) – 23.34 %, Baetis rhodani – 18.66 % and B. vernus Curtis, 1834 – 15.25 %] and far exceeded the level of intraspecific variability of the COI fragment based on the BOLD standards. The sequences of 23 individuals determined as Habroleptoides confusa, Baetis rhodani, B. buceratus Eaton, 1870, Caenis beskidensis Sowa, 1973 and Torleya major (Klapálek, 1905) created seven unique BINs, which represent the distant phylogenetic lineages of already existing BINs, that are currently unique to Slovakia. The coexistence of Baetis rhodani individuals of two different BINs was confirmed at five localities. Our study indicates clear importance of more detailed sampling and DNA barcoding due to the presence of unexpected intraspecific genetic diversity of mayflies captured in a relatively small area of the Western Carpathians.

Can vertebral remains differentiate more than one species of Australian Cretaceous ichthyosaur?

All currently described Cretaceous ichthyosaur remains in Australia have been referred to the single taxon Platypterygius australis M’Coy 1867, primarily on the basis of skull morphology. This research set out to determine if specimens could be attributed to P. australis on the basis of vertebral data alone. Vertebrae were measured and subjected to morphometric analysis for specimens previously attributed to P. australis, along with several unattributed specimens that either lack skulls or where existing skulls have not been described. Centrum length (CL) plots, together with a principle components analysis and multivariate analysis of variance, suggest that different specimens can be distinguished from each other on the basis of vertebrae. Although our analyses using only basic centrum dimensions are heavily impacted by size, and thus growth stage of individuals, two specimens previously attributed to P. australis on the basis of skull morphology alone plotted separately from each other in all analyses, with one plotting consistently near the outgroup taxon, Ophthalmosaurus natans (Marsh, 1879). Hence, the data are consistent either with very large intraspecific variation within vertebral patterns, or support the possibility that more than one Australian species occurs in the dataset. CL and multivariate data showed that juvenile ichthyosaurs plot differently relative to all subadults–adults, not only in their proportionately smaller vertebrae, but also in having consistently different shapes with little difference between the length of dorsal and caudal vertebrae. One subadult individual (RGC1) also showed similarity in length between dorsal and caudal vertebrae and has abnormal rib facets. We posit that it could either be an aberrant P. australis, or an otherwise unknown taxon. Although additional material is required, questions raised by this study suggest the need to test the postcranial remains of additional specimens, especially those with well-studied skulls, so as to identify the level of intraspecific variation or any sexual dimorphism, and to determine if any as yet undetected ichthyosaur taxa occurred in the Australian Early Cretaceous. Vikram Vakil [ vikram.vakil@uqconnect.edu.au ], Gregory E. Webb [ g.webb@uq.edu.au ] and Alex G. Cook [ alex.cook@y7mail.com ] School of Earth & Environmental Sciences, The University of Queensland, St Lucia, Brisbane, Queensland 4072, Australia.

Sex-specific ontogenetic patterns of cranial morphology, theoretical bite force, and underlying jaw musculature in fishers and American martens.

The carnivoran cranium undergoes tremendous growth in size and development of shape to process prey as adults and, importantly, these ontogenetic processes can also differ between the sexes. How these ontogenetic changes in morphology actually relate to the underlying jaw musculature and overall bite performance has rarely been investigated. In this study, I examined sex-specific ontogenetic changes in cranial morphology, jaw adductor muscles, and theoretical bite force between subadults and adults in the fisher (Pekania pennanti) and American marten (Martes americana). I found evidence that cranial size alone does not completely explain ontogenetic increases in bite forces as found in other mammalian species. Instead, cranial shape development also drives ontogenetic increases in relative bite force by broadening the zygomatic arches and enlargement of the sagittal crest, both of which enable relatively larger jaw adductor muscles to attach. In contrast, examination of sexual dimorphism within each age-class revealed that cranial shape dimorphism did not translate to dimorphism in either size-corrected bite forces or size-corrected physiological cross-sectional area of the jaw adductor muscles. These results reveal that morphological size and shape variation can have different influences on bite performance depending on the level of intraspecific variation that is examined (i.e. ontogenetic versus sexual dimorphism).

Intraspecific variability in response to phosphorus depleted conditions in the cyanobacteria Microcystis aeruginosa and Raphidiopsis raciborskii

Phosphorus loading plays an important role in the occurrence of cyanobacterial blooms and understanding how this nutrient affects the physiology of cyanobacteria is imperative to manage these phenomena. Microcystis aeruginosa and Raphidiopsis raciborskii are cyanobacterial species that form potentially toxic blooms in freshwater ecosystems worldwide. Blooms comprise numerous strains with high trait variability, which can contribute to the widespread distribution of these species. Here, we explored the intraspecific variability in response to phosphorus depleted conditions (P-) testing five strains of each species. Strains could be differentiated by cell volume or genetic profiles except for those of the same species, sampling location and date, though these presented differences in their response to (P-). Although differently affected by (P-) over 10 days, all strains were able to grow and maintain photosynthetic activity. For most M. aeruginosa and R. raciborskii strains growth rates were not significantly different comparing (P+) and (P-) conditions. After ten days in (P-), only one M. aeruginosa strain and two R. raciborskii strains showed reduction in biovolume yield as compared to (P+) but in most strains chlorophyll-a concentrations were lower in (P-) than in (P+). Reduced photosystem II efficiency was found for only one R. raciborskii strain while all M. aeruginosa strains were affected. Only two M. aeruginosa and one R. raciborskii strain increased alkaline phosphatase activity under (P-) as compared to (P+). Variation in P-uptake was also observed but comparison among strains yielded homogeneous groups comprised of representatives of both species. Comparing the response of each species as a whole, the (P-) condition affected growth rate, biovolume yield and chlorophyll yield. However, these parameters revealed variation among strains of the same species to the extent that differences between M. aeruginosa and R. raciborskii were not significant. Taken together, these results do not support the idea that R. raciborskii, as a species, can withstand phosphorus limitation better than M. aeruginosa and also point that the level of intraspecific variation may preclude generalizations based on studies that use only one or few strains.

Low genetic connectivity in a fouling amphipod among man-made structures in the southern North Sea

Offshore environments are increasingly invaded by man-made structures that form hard-substrate habitats for many marine species. Examples include oil and gas platforms, wind turbines and shipwrecks. One of the hypothesised effects is an increased genetic connectivity among natural populations due to new populations growing on man-made structures that may act as stepping stones. However, few data are available on genetic connectivity among organisms inhabiting artificial offshore structures. Here, we present a study on the common fouling amphipod Jassa herdmani from offshore structures in the southern North Sea. Partial mitochondrial DNA sequences (cytochrome-c-oxidase 1, N = 514) were obtained from artificial structures at 17 locations in the southern North Sea, including 13 shipwrecks, 2 wind turbines and 2 platforms. Samples from these locations were significantly differentiated, meaning that strong population structure exists for this species in the area. Levels of intraspecific variation were consistent with stable population sizes. No evidence was found for isolation by distance. Using coalescent simulations, the oldest population subdivision events were estimated to date back to the time the study area was flooded following the Last Glacial Maximum. We therefore tentatively conclude that J. herdmani may have colonised man-made structures from previously existing populations on the sea floor, and that the increase in offshore installations has not led to an overall increase in genetic connectivity for this species.

Genetic structure among Charadrius plovers on the African mainland and islands of Madagascar and St Helena

Colonization of islands by long‐distance dispersers has great impact on genetic diversification among populations and may spearhead speciation events. We investigated intra‐ and interspecific divergence in Charadrius plovers with populations on mainland Africa, Madagascar and St Helena. We analysed microsatellite loci and sequence data from four nuclear and two mitochondrial gene regions. Charadrius plovers are shorebirds with high dispersal and mobility. Our results confirmed genetic differentiation between Madagascar and mainland populations of three plover species (White‐fronted Plover Charadrius marginatus, Kittlitz's Plover Charadrius pecuarius and, based on sequence data only, Three‐banded Plover Charadrius tricollaris) but highlight substantial variation in levels of intraspecific divergence among the three species. Namely, the Kittlitz's Plover, a dispersive habitat generalist with a polygamous mating system, exhibited lower island–mainland differentiation (0.05% COI sequence divergence) compared with the two monogamous species, the White‐fronted Plover (0.6% COI divergence) and Three‐banded Plover (1.6% COI divergence). In addition, past colonization of the islands of St Helena and Madagascar by ancestors of today's Kittlitz's Plover has led to the evolution of two endemic island species, the Madagascar Plover Charadrius thoracicus and the more closely‐related St Helena Plover Charadrius sanctaehelenae. We discuss the factors driving species differences in island–mainland divergence and highlight the importance of conserving genetically unique island populations and island habitats to safeguard future evolutionary potential.

Intraspecific variation in semicircular canal morphology—A missing element in adaptive scenarios?

Recent evidence suggests that the amount of intraspecific variation in semicircular canal morphology may, itself, be evidence for varying levels of selection related to locomotor demands. To determine the extent of this phenomenon across taxa, we expand upon previous work by examining intraspecific variation in canal radii and canal orthogonality in a broad sample of strepsirrhine and platyrrhine primates. Patterns of interspecific variation are re-examined in light of intraspecific variation to better understand the resolution at which locomotion can be reconstructed from single individuals. Data was collected from high-resolution CT scans of 14 size-matched, related species. Six of these taxa have existing data on rotational head speeds. The level of intraspecific variation was found to differ in strepsirrhine and in platyrrhine species pairs, with larger ranges of variation generally observed for the slower moving taxon than the faster moving one. Taxa that are classified as relatively agile can to some extent be separated from those who are slower-moving, but only when comparing similarly sized, closely related species with more extreme forms of locomotion. Our findings agree with previous research showing that canal intraspecific variation can fluctuate according to species-specific locomotor behavior and extends this further by identifying behaviors that may be under unusual selective pressure. It also demonstrates the complexity of interpreting inner ear morphology in the context of broadly applicable locomotor "categories" of the kind commonly used in behavioral studies. We suspect that simplified models predicting vestibular sensitivity may be unable to differentiate behaviors when only a single specimen is available.

Phylogeography reveals a North Island range extension for New Zealand's only sexually wing-dimorphic stonefly (Stenoperla helsoni)

ABSTRACTStenoperla helsoni is an endemic New Zealand stonefly characterised by distinctive sexually dimorphic wing loss. Previous distribution records indicated that this species was restricted to the South Island's Southern Alps, although our recent collections of wing-reduced specimens from a site in the Tararua Ranges suggest that this species may extend into the lower North Island. We amplified the mitochondrial COI gene to confirm the identity of North Island specimens, and to assess phylogeographic structuring within the species and genus. North Island specimens were confirmed as S. helsoni, indicating that this species has a much wider geographic range than previously thought. This broad distribution, combined with low levels of intraspecific divergence, suggests that female S. helsoni may be strong fliers, despite males being flightless. Distinct North Island and South Island populations were identified, with a 1.5% divergence between the two populations.

Climate Change Impacts on Seagrass Meadows and Macroalgal Forests: An Integrative Perspective on Acclimation and Adaptation Potential

Marine macrophytes are the foundation of algal forests and seagrass meadows¬–some of the most productive and diverse coastal marine ecosystems on the planet. These ecosystems provide nursery grounds and food for fish and invertebrates, coastline protection from erosion, carbon sequestration, and nutrient fixation. For marine macrophytes, temperature is generally the most important range limiting factor, and ocean warming is considered the most severe threat among global climate change factors. ocean warming induced losses of dominant macrophytes along their equatorial range edges, as well as range extensions into polar regions, are predicted and already documented. While adaptive evolution based on genetic change is considered too slow to keep pace with the increasing rate of anthropogenic environmental changes, rapid adaptation may come about through a set of non-genetic mechanisms involving the functional composition of the associated microbiome, as well as epigenetic modification of the genome and its regulatory effect on gene expression and the activity of transposable elements. While research in terrestrial plants demonstrates that the integration of non-genetic mechanisms provide a more holistic picture of a species' evolutionary potential, research in marine systems is lagging behind. Here, we aim to review the potential of marine macrophytes to acclimatize and adapt to major climate change effects via intraspecific variation at the genetic, epigenetic, and microbiome levels. All three levels create phenotypic variation that may either enhance fitness within individuals (plasticity) or be subject to selection and ultimately, adaptation. We review three of the most important phenotypic variations in a climate change context, including physiological variation, variation in propagation success, and in herbivore resistance. Integrating different levels of plasticity, and adaptability into ecological models will allow to obtain a more holistic understanding of trait variation and a realistic assessment of the future performance and distribution of marine macrophytes. Such multi-disciplinary approach that integrates various levels of intraspecific variation, and their effect on phenotypic and physiological variation, is of crucial importance for the effective management and conservation of seagrasses and macroalgae under climate change.

Molecular Phylogenetic Positions and Ultrastructure of Marine Gregarines (Apicomplexa) Cuspisella ishikariensis n. gen., n. sp. and Loxomorpha cf. harmothoe from Western Pacific scaleworms (Polynoidae).

Marine gregarines are unicellular parasites of invertebrates commonly found infecting the intestine and coelomic spaces of their hosts. Situated at the base of the apicomplexan tree, marine gregarines offer an opportunity to explore the earliest stages of apicomplexan evolution. Classification of marine gregarines is often based on the morphological traits of the conspicuous feeding stages (trophozoites) in combination with host affiliation and molecular phylogenetic data. Morphological characters of other life stages such as the spore are also used to inform taxonomy when such stages can be found. The reconstruction of gregarine evolutionary history is challenging, due to high levels of intraspecific variation of morphological characters combined with relatively few traits that are taxonomically unambiguous. The current study combined morphological data with a phylogenetic analysis of small subunit rDNA sequences to describe and establish a new genus and species (Cuspisella ishikariensis n. gen., n. sp.) of marine gregarine isolated from the intestine of a polynoid host (Lepidonotus helotypus) collected from Hokkaido, Japan. This new species possesses a set of unusual morphological traits including a spiked attachment apparatus and sits on a long branch on the molecular phylogeny. Furthermore, this study establishes a molecular phylogenetic position for Loxomorpha cf. harmothoe, a previously described marine gregarine, and reveals a new group of gregarines that infect polynoid hosts.

Ntra-species profiling of Cleome viscosa growing in Swat district (Pakistan)

Intra-specific genetic variation was studied in 28 genotypes of Cleome viscosa L. growing in Swat district, Khyber Pakhtunkhwa, Pakistan. It was found that genotypes showed the utmost allelic variation for leaf upper and lower surface with emerald green (75%), and yellow green (75%) respectively, other leaves lower and upper surfaces were (25%) green and yellow green (26%) respectively. The majority of C. viscosa genotypes were (50%) yellow flowers while others were with (29%) white yellow colour and (21%) dull yellow. Most of the seeds were with black (46%). The protein profiling was carried out on 12% gel electrophoresis; seven reproducible bands with molecular weight ranges from 180 to 10 KDa were detected in C. viscosa, the locus contribution toward genetic disagreement (LCTGD) of C. viscosa was 57%. Notably, L-3, L-4 L-5, was monomorphic in C. viscosa and was treated as species specific. L-1, L-2, L-7 were polymorphic. These bands showed 79%, 4%, 14% and 79% variation respectively. In the current investigation the intra-specific variation was observed limited and alone SDS-PAGE did not determine the high level of intra-specific variation; however, diverse germplasm were suggested to be acquired from various sources.

DNA barcoding for species identification in deep-sea clams (Mollusca: Bivalvia: Vesicomyidae)

Deep-sea clams (Bivalvia: Vesicomyidae) have been found in reduced environments over the world oceans, but taxonomy of this group remains confusing at species and supraspecific levels due to their high-morphological similarity and plasticity. In the present study, we collected mitochondrial COI sequences to evaluate the utility of DNA barcoding on identifying vesicomyid species. COI dataset identified 56 well-supported putative species/operational taxonomic units (OTUs), approximately covering half of the extant vesicomyid species. One species (OTU2) was first detected, and may represent a new species. Average distances between species ranged from 1.65 to 29.64%, generally higher than average intraspecific distances (0–1.41%) when excluding Pliocardia sp.10 cf. venusta (average intraspecific distance 1.91%). Local barcoding gap existed in 33 of the 35 species when comparing distances of maximum interspecific and minimum interspecific distances with two exceptions (Abyssogena southwardae and Calyptogena rectimargo-starobogatovi). The barcode index number (BIN) system determined 41 of the 56 species/OTUs, each with a unique BIN, indicating their validity. Three species were found to have two BINs, together with their high level of intraspecific variation, implying cryptic diversity within them. Although fewer 16 S sequences were collected, similar results were obtained. Nineteen putative species were determined and no overlap observed between intra- and inter-specific variation. Implications of DNA barcoding for the Vesicomyidae taxonomy were then discussed. Findings of this study will provide important evidence for taxonomic revision in this problematic clam group, and accelerate the discovery of new vesicomyid species in the future.