Ecomorphology of the giant bear-dogs Amphicyon and Ischyrocyon

Giant bear-dogs of the genera Amphicyon and Ischyrocyon (Carnivora, Amphicyonidae, Amphicyoninae) were the largest carnivorans in North America during middle and late Miocene (17.5–8.8 Mya) with a dental and skeletal morphology that combined features found in living Ursidae, Canidae, and Felidae. This study tests previously proposed models of diet and hunting behaviour of these extinct carnivorans. Relative grinding area (RGA) of lower molars and wear pattern on upper molars suggest that bear-dogs were carnivorous. Amphicyon and Ischyrocyon possessed skeletal features of both ambush (short distal limb segments) and pursuit (caudally bent olecranon process of ulna) living predators. Therefore, bear-dogs probably pursued their prey (mediportal ungulates) for a longer distance but at a slower speed than do living ambush predators. Upon catching up to its prey a bear-dog probably seized it with powerfully muscled forelimbs and killed it by tearing into its ribcage or neck with canines set in a narrow rostrum.     

A field experiment on the use of Pistacia lentiscus L. and Scrophularia canina L. subsp. bicolor (Sibth. et Sm.) Greuter for the phytoremediation of abandoned mining areas

Abstract

A two-year study has been conducted in an abandoned Pb/Zn mining site, with the aim of investigating the feasibility of phytoremediation using two native Mediterranean plants (Pistacia lentiscus and Scrophularia bicolor) and of assessing the performance of amendments able to reduce the toxic effects of heavy metals. The amendments used were compost, chemical fertilizer, and zeolites, used singly or in combination. Depending on the amendments applied, the two species showed different mortality rates in the different plots, but all produced an increase in P. lentiscus survival, while S. bicolor survival improved only when amended with zeolite or zeolite + fertilizer. Scrophularia bicolor proved to be a more efficient accumulator than P. lentiscus, especially for Pb uptake. Pistacia lentiscus accumulated metals mostly in the roots. The effect of amendments was to generally reduce the bioavailable metal fraction, especially lead, in the plots amended with compost. Pistacia lentiscus proved to be the most suitable species for phytostabilization and environmental restoration, both for its resistance to metals and high phytomass production. The experiments demonstrate that the use of compost not only encourages this kind of revegetation in degraded areas, but is also an economical option that uses a by-product of solid municipal waste treatment.     

Asperula calabra (Rubiaceae) and allied taxa in southern Apennines,Italy

The present work is aimed at studying several Asperula (Rubiaceae) sect. Cynanchicae populations in southern Apennines, Italy, with particular reference to those referred to A. calabra, by employing biometrical methods on macromorphological data. Among other historical misapplications, A. cynanchica subsp. cynanchica seems to be very rare or missing in southern Italy. The enigmatic Asperula calabra, confirmed to be limited to a single mountain population in Calabria, appears to be strictly related to A. aristata subsp. scabra, so we suggest to treat it as a further subspecies of A. aristata. This latter species is otherwise distributed throughout southern Italy with subsp. scabra and subsp. aristata, characterised by slight morphological differences, which are correlated to altitudinal ranges.     

Molecular identification of root fungal associates in Orchis pauciflora Tenore

Abstract

The terrestrial orchid, Orchis pauciflora Ten., growing in poor grassland and garrigue of Central Mediterranean region, is local and rare and has been included in the red lists of several Italian regions. We investigated the diversity of fungal associates in O. pauciflora adult plants collected in two protected areas of Tuscany (Central Italy). Genomic DNA was extracted from mycorrhizal roots of 12 orchid plants and the fungal ITS were amplified and sequenced. Several fungal associates, belonging to different taxa of basidiomycetes (Tulasnellaceae) and ascomycetes such as Leptodontidium, Exophiala and Phialophora species, were recovered. The trophic role of these fungi and their impact on O. pauciflora growth and conservation are discussed.     

Prenylated flavonoids and total extracts from Morus nigra L. root bark inhibit in vitro growth of plant pathogenic fungi

Total extracts and kuwanon G from Morus nigra root bark showed antifungal activity against several phytopathogenic fungi, with minimal inhibitory concentration (MIC₅₀) ranging from 32 to 128 μg/ml and from 16 to 64 μg/ml, respectively. Acetonic extracts inhibited 60% B. cinerea biofilm formation at concentration of 128 μg/ml.     

Seed germination in the Sicilian subspecies of Dianthus rupicola Biv. (Caryophyllaceae)

Abstract

Five populations belonging to three subspecies of Dianthus rupicola Biv. (D. rupicola subsp. rupicola, D. rupicola subsp. aeolicus, and D. rupicola subsp. lopadusanus) and growing in different geographical areas of Sicily were tested for seed germination at various temperatures. All populations showed high germination rates with an optimum temperature between 15°C and 25°C. Efficient seed germination might contribute significantly to the preservation of these subspecies which are currently exposed to several environmental threats.     

Chemical profile and biological activities of Cedrelopsis grevei H. Baillon bark essential oil

Cedrelopsis grevei H. Baillon bark, endemic plant from Madagascar, is used in folk medicine for the treatment of rheumatism, muscular pain, and for its antifungal and antibiotic activities. In this paper, the phytochemical composition, antioxidant, antimicrobial, and cytotoxic activities of C. grevei bark essential oil (EO), its non-polar (I and II) and polar (III) fractions and its main compounds (ishwarane, β-elemene and α-copaene) were investigated.

The GC–MS analysis pointed out the presence of 36 components, representing about 80% as semi-quantitative characterization of the total. The presence of ishwarane, β-elemene and α-copaene as the main constituents highlighted its peculiar composition as a sesquiterpene-rich phytocomplex. Moreover, the quantification was performed for the first time by means of the experimental and predicted response factors (ERFs and PRFs, respectively).

As regards the biological activity, C. grevei EO and its fractions showed weak antioxidant activity against Trolox. The whole EO demonstrated instead considerable antimicrobial activity against Staphylococcus aureus and Staphylococcus epidermidis, while its polar-fraction evidenced an interesting bioactivity against Pseudomonas aeruginosa and Candida albicans. Finally, C. grevei EO and its fractions exhibited an interesting cytotoxic activity on human lung cancer cells (A549) and human colorectal cancer cells (CaCo-2).     

Phytochemical analysis and antibacterial activity towards methicillin-resistant Staphylococcus aureus of leaf extracts from Argania spinosa (L.) Skeels

Argania spinosa (L.) Skeels is an endemic Moroccan species belonging to Sapotaceae family. In this work, lipophilic and aqueous extracts were obtained from leaves and subjected to a chemical profiling by MS and LC-MS/MS. Pentacyclic terpenoids were identified and quantified in the lipophilic fraction, while phenolic compounds (mainly belonging to flavonols and flavan-3-ols) were identified in the aqueous fraction. The antibacterial activities of fractions were evaluated in vitro against both reference Gram-positive and -negative bacterial strains and clinical isolates of methicillin-sensitive and methicillin-resistant Staphylococcus aureus (MSSA and MRSA); in addition, the compounds quantified as main components in each extract were assayed against reference strains. A relevant antibacterial activity was observed against reference MSSA and MRSA strains of S. aureus: for the lipophilic fraction, MIC₅₀ values obtained were 177.8 and 170.6 μg/mL for the former and the latter, respectively, while for the aqueous fraction were 215.5 and 233.3 μg/mL. These inhibitory activities could be mainly ascribed to ursolic and oleanolic acids, among pentacyclic terpenoids, and to quercetin concerning phenolic compounds. A remarkable antibacterial activity was also observed against clinical isolates, thus argan leaves can be considered of interest in the chemotherapy of human infections.     

Submediterranean dry grasslands along the Tyrrhenian sector of central Italy: Synecology,syndynamics and syntaxonomy

Abstract

Semi-natural dry grasslands are habitats of high conservation concern. These ecosystems have not been extensively explored in the Tyrrhenian sector of the Italian peninsula, particularly in the Submediterranean climatic region. In order to address this issue and to define the synecology, syndynamics and syntaxonomy of calcareous grasslands in this area, we considered 127 phytosociological relevés. Our sampling was performed in the Lazio region according to a stratified sampling scheme based on homogeneous land units, defined by means of an ecological land classification process. We analyzed the vegetation data using multivariate methods. Two new associations, whose typical aspects occur in the mesotemperate phytoclimatic belt, were identified:Erysimo pseudorhaetici-Dasypyretum villosi (Taenianthero-Aegilopion) and Scorpiuro muricati-Brometum erecti (Phleo-Bromion). Phytoclimatic belts within the Submediterranean region cause a significant degree of differentiation within Scorpiuro-Brometum, which was described at the subassociation and variant levels. The overall relevance of therophytes represents the most important feature distinguishing Scorpiuro-Brometum from the published Bromus erectus associations. At a finer scale, the presence of the two physiognomically different grassland communities is related to different soil types. All these communities are dynamically linked to Quercus virgiliana and Q. pubescens woods, and contribute to the coenological differentiation of the vegetation series related to such woodlands.     

Biomass and nutrient dynamics in Mediterranean seasonal dimorphic shrubs: Strategies to face environmental constraints

Abstract

To analyze biomass and nutrient dynamics of Mediterranean seasonal dimorphic shrubs, aboveground biomass (AGB) and belowground biomass (BGB), litterfall (LF), aboveground net annual primary production (ANPP), and nutrient allocation and turnover were estimated in Cistus salviifolius and C. ladanifer, during two years, in southern Portugal. AGB, BGB, LF, and ANPP of C. salviifolius are within the range reported for other seasonal dimorphic plants, while those of C. ladanifer are closer to evergreen sclerophylls. Leaf renewal was higher for C. salviifolius than for C. ladanifer, especially for winter leaves, while root-to-shoot ratio and accumulation of live wood was greater in the latter. The concentrations of N, K, Ca, and Mg were lower in leaves of C. ladanifer than in those of C. salviifolius, suggesting less nutritive requirements for the former. Moreover, leaf nutrient translocation was higher in C. ladanifer than in C. salviifolius. Therefore, C. ladanifer shrubs seem to be more efficient with respect to carbon uptake, even during severe drought, while those of C. salviifolius act as weaker sinks more susceptible to the negative effects of drought. Additionally, C. ladanifer seems to have a competitive advantage in more arid conditions, as a great proportion of its annual nutrient requirement may derive from internal sources.     

Festuca and allied genera (Poaceae) as Crop Wild Relatives: Checklists and Red Lists are urgently required

Festuca s.l. is a crucial group of Crop Wild Relatives (CWR) genera, globally employed as fodder, lawn grasses and for habitat restoration. Lists elaborated strictly on the basis of a taxonomic approach are urgently needed to be used to find gaps in existing ex situ collections, to assess the conservation status of taxa of ascertained utility and include them in national Red Lists and to identify the most valuable taxa to be included in “preservation mixtures”, as per Commission Directive 2010/60/EU. As an example, the first taxonomically based priority list of Italian CWRs of Festuca s.l. is here provided.     

In vitro propagation of Leucocroton havanensis Borhidi (Euphorbiaceae): A rare serpentine-endemic species of Cuba

Leucocroton havanensis Borhidi is an endemic plant species of Cuba able to hyperaccumulate nickel. In order to sustain the conservation of this species, an efficient protocol for its micropropagation, via axillary bud proliferation, is described. We placed apical segments from aseptic seedlings on basal medium supplemented with indole-3-acetic acid (IAA) and 6-benzylaminopurine (BAP) or thidiazuron (TDZ), individually or in combination. On a medium containing 0.5 mg L^?1 IAA and 1.0 mg L^?1 BAP explants (65.5%) developed axillary buds. Nevertheless, combinations of 0.5 mg L^?1 IAA with 0.1 mg L^?1 TDZ was the most effective treatment producing the highest number of buds per explant (30.3); while the control treatment, without growth regulators, produced no buds at all. Transfer of buds to medium supplemented with indole-3-butyric acid, indicated that 0.25 mg L^?1 is the amount of hormone required to generate roots on young buds (100%). In order to assess DNA variations in micropropagated plants, an Amplified Fragment Length Polymorphism analysis was performed and no genetic variation was detected. This study demonstrates that a high multiplication rate can be obtained by means of the reported protocol, and that plantlets can be readily hardened (96% survival) in a greenhouse by transplanting them on serpentine soil.     

A Parvancorina-like arthropod from the Cambrian of South China

Constraining the origin of animal groups is allowed, to some extent, by discoveries of Cambrian Lagerstätten that preserve both mineralizing and nonmineralizing organisms. A new species is reported here of the Cambrian arthropod Skania, which bears an exoskeleton that shares homologies with the Neoproterozoic (Ediacaran) organism Parvancorina and firmly establishes a Precambrian root for arthropods. A new monophyletic group, Parvancorinomorpha, is proposed as the first clade within the arthropod crown group demonstrably ranging across the Neoproterozoic–Paleozoic transition. The Parvancorinomorpha is interpreted to be the sister group of the Arachnomorpha. Incipient cephalization in Skania and related genera represents a step in the progression toward division of a cephalon from a large posterior trunk as shown in Cambrian arachnomorphs such as naraoiids and the addition of a pygidium and thoracic tergites as shown in the arachnomorph clade basal to trilobites. This evidence can serve as a new calibration point for estimating the divergence time for the last common ancestor of arthropods and priapulids based on molecular clock methods.     

Morphological analysis,chorology and ecology of Juniperus navicularis Gand. in the Iberian Peninsula

Juniperus navicularis is an endemic taxon of Iberian Peninsula that develops on paleodunes of coastal ecosystems and whose distribution range is not well defined. In this paper, we present the results of the morphological analysis in populations attributed to J. navicularis of southern Spain. In order to assess the similarity between Portuguese and Spanish populations, the Mann–Whitney U test was performed, the same test was also applied between this taxon and Juniperus oxycedrus subsp. oxycedrus. In order to distinguish this species from other taxa of the Juniperus oxycedrus group (subsp. oxycedrus, subsp. badia, subsp. macrocarpa) in the southwestern Mediterranean region, a principal component analysis has been carried out. New data about the chorology and ecology of Spanish populations considered as a priority habitat in the Habitat Directive as well as number of individuals and conservation status are provided.     

Diurnal variations in physiology and behaviour of the noble crayfish Astacus astacus and the signal crayfish Pacifastacus leniusculus

Heart rate, locomotor activity, and oxygen consumption were recorded simultaneously and continuously in seven individuals of the noble crayfish Astacus astacus (Linneus 1758) and seven individuals of the signal crayfish Pacifastacus leniusculus (Dana 1852). The recordings were made in the laboratory over 7 days at 15°C under a 12?:?12?h dark?:?light regime. Circadian rhythms in heart rate, locomotor activity and oxygen consumption were found both in A. astacus and P. leniusculus. Increased heart rate, locomotor activity, and oxygen consumption levels during night time in both A. astacus and P. leniusculus illustrated expression of nocturnal behaviour. No differences in oxygen consumption levels were observed between A. astacus and P. leniusculus. Also, no significant difference between heart rate levels or heart rate variances was found in A. astacus and P. leniusculus at night. During day, however, heart rate levels, heart rate variances and locomotor activity were higher in P. leniusculus than in A. astacus. The higher activity level in P. leniusculus than in A. astacus during daytime indicates that P. leniusculus is less strictly nocturnal than is A. astacus.     

Defoliation of common ragweed by Ophraella communa beetle does not affect pollen allergenicity in controlled conditions

Ragweed allergy is one of the primary causes of seasonal allergies in Europe and its prevalence is expected to rise. The leaf beetle Ophraella communa, recently and accidentally established in N-Italy and S-Switzerland, represents a promising approach to control ragweed, but negative side effects should be excluded before its use. Since biotic and abiotic stresses are known to influence the allergenicity of pollen, we set out to assess the effect of sub-lethal defoliation by O. communa on the quantity and quality of ragweed pollen. Seventeen sister pairs (including six clones) of ragweed plants were grown in controlled conditions. One of each pair was exposed to O. communa as soon as the plant started to produce reproductive structures. After 10 weeks of exposure, plant traits were measured as a proxy for pollen quantity. Pollen quality was assessed by measuring its viability and allergenicity. Generally, plants produced very few male flowers and little amount of pollen. Damage by the beetle was severe with most of the leaf tissue removed, but no treatment effect was found on any of the quantitative and qualitative traits assessed. In conclusion, O. communa did not increase the amount or allergenicity of ragweed pollen grains in our experimental conditions.     

Panicum spikelets from the Early Holocene Takarkori rockshelter (SW Libya): Archaeo-molecular and -botanical investigations

This paper deals with the extraction, amplification and sequencing of ancient DNA (aDNA) from spikelets of wild cereals dated at ca. 9000 cal yr BP, representing the most ancient plants with preserved genetic material from the Sahara desert. The sub-fossil records were collected from the archaeological excavation carried out at Takarkori, an archaeological site located in south-western Libya. Morphological and genetic analyses were made on 100 well preserved dried spikelets. Ten DNA extraction protocols were performed to evaluate nucleic acid recovery in terms of DNA yield, purity and amplification success of the chloroplast barcode region matK. The extraction protocol that returned the most suitable DNA to be amplified is the Kistler and Shapiro (2011: J Archaeol Sci 38: 3549-3554) modified protocol. In our study, the results from matK amplification suggested that four specimens are the most appropriate number of spikelets for these analyses. DNA was then used for PCR amplifications of four chloroplast barcode genes: rbcL, matK, trnH-psbA and trnL. A phylogenetic analysis shows the strict relation between the archaeological specimens and modern Panicoideae, supporting the morphological identification. The results indicate that spikelets have a close relation to Panicum laetum Kunth, a wild cereal still collected in tropical Africa.     

Gametophyte development and reproduction of the Asian fern Polystichum polyblepharum (Roem. ex Kunze) C. Presl (Dryopteridaceae,Polypodiopsida)

Abstract

The gametophytic generation of Polystichum polyblepharum (Dryopteridaceae), including spore germination, morphological development of the gametophytes, major vegetative features and reproduction strategies, was studied. Spore germination was of the Vittaria model and the developmental pattern was of the Aspidium model. Adult gametophytes were cordate and hairy, with unicellular hairs located at the margins and at the prothallus surface. The marginal ones were secretory. The gametophytes produced archegonia located in the central area between the notch and the rhizoids, but antheridia were never detected. Archegonia were of the normal type described for leptosporangiate ferns. Apogamous sporophytes appeared from a cellular outgrowth developed just under the apical notch. Initially, the outgrowth appeared completely surrounded by glandular hairs and scales, which persisted throughout the subsequent stages of leaf development.     

Taxonomic implications of foliar epidermis in Impatiens (Balsaminaceae): Investigating 12 Pakistani taxa as an example

Impatiens L. is taxonomically a complicated genus that necessitates fresh characterization to resolve its taxonomy. This study therefore aimed at ascertaining micro-morphological characters in the foliar epidermis of Impatiens. For this purpose, we gathered twelve taxa (10 species and 2 subspecies) mostly from the northern regions of Pakistan and studied qualitative and quantitative characters depicting variation in epidermal cells, stomata, and trichomes on both surfaces. Multicellular, uniseriate trichomes were observed only in I. balsamina L., and raphides in I. balfourii Hook. f. and I. thomsonii Hook. f. while stomata were exclusively anomocytic in all species. Morphological variation in the foliar epidermal characters and their diagnostic value has been depicted by constructing a taxonomic key to all taxa. The study revealed that although foliar epidermal characters in Impatiens did not desirably assort taxa on the basis of structural topographies, yet demonstrated adequate variation distinguishing the Pakistani taxa.