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Juan M Pleguezuelos - One of the best experts on this subject based on the ideXlab platform.

  • reproduction ecology of the recently invasive snake hemorrhois Hippocrepis on the island of ibiza
    Current Zoology, 2020
    Co-Authors: Elba Montes, Esmeralda Alaminos, Monica Feriche, Leticia Ruizsueiro, Juan M Pleguezuelos
    Abstract:

    Knowing the causes of biological invasion success can be relevant to combat future invasive processes. The recent invasion of the horseshoe whip snake Hemorrhois Hippocrepis on the island of Ibiza provides the opportunity to compare natural history traits between invasive and source populations, and to unravel what makes this snake a successful invader that is threatening the only endemic vertebrate of the island, Podarcis pityusensis. This study compares the basic reproductive traits of mainland native and invasive populations of the snake. Our results revealed that invasive populations were characterized by female maturity at a smaller size, extended reproductive period, and much lower reproduction frequency compared to the native population. In contrast, some major reproductive traits-the abdominal fat body cycle, clutch size, hatchling body size, and hatchling body condition, did not differ between the two populations. Some of these results must reflect the environmental differences in the recently invaded island with respect to the source area, and overall plasticity of reproductive traits. Plasticity is evolutionarily interesting, and may aid the successful growth of this species in their invasiveness of Mediterranean islands like Ibiza. The most significant finding is that this expression of phenotypic plasticity occurred rapidly in this invasive population, within a period of 14 years maximum. Our results on the reproduction ecology of the invasive population were not conclusive regarding the factors determining the invasiveness of the snake and pointed to alternative causes.

  • exploring body injuries in the horseshoe whip snake hemorrhois Hippocrepis
    Acta Herpetologica, 2018
    Co-Authors: Juan M Pleguezuelos, Esmeralda Alaminos, Monica Feriche
    Abstract:

    Body injuries on snakes may serve as indices of predation rate, which is otherwise difficult to record by direct methods because of the usual scarcity and shy nature of these reptiles. We studied the incidence of body scarring and tail breakage in a Mediterranean colubrid, Hemorrhois Hippocrepis , from south-eastern Spain. This species exhibits two traits that favour tail breakage, a long tail and active foraging tactics. The large sample (n = 328) of individuals acquired also enabled us to determine how the incidence of these injuries varies ontogenetically, between the sexes, in relation to energy stores, and to seek for the possible existence of multiple tail breakage. Overall, the incidence of tail breakage was rather low (13.1%) and similar to that of body scarring (12.7%). However, there was a significant ontogenetic shift in the incidence of tail breakage; such injuries barely appeared in immature snakes but stub-tailed individuals were present in 38.7% of snakes in the upper decile of body size. In contrast to most other studies, our data show a sex difference in the incidence of these injuries, adult male rates quadrupling those of adult females for body scarring and males maintaining larger stubs, probably because of the presence of copulatory organs housed in the base of the tail. Larger individuals did not have shorter tail stubs, a finding that does not support the multiple-tail-breakage hypothesis. Our results also fail to support the idea of a cost of tail breakage or body scarring in terms of body condition.

  • The fall of a symbol? A high predation rate by the introduced horseshoe whip snake Hemorrhois Hippocrepis paints a bleak future for the endemic Ibiza wall lizard Podarcis pityusensis
    European Journal of Wildlife Research, 2016
    Co-Authors: Arlo Hinckley, Elba Montes, Enrique Ayllón, Juan M Pleguezuelos
    Abstract:

    Invasive species currently account for a major threat to global biodiversity, and island ecosystems are among the most vulnerable, because of the frequency and success of species introductions on islands. Within Mediterranean islands, reptiles not only are frequently introduced species but are also among the most threatened because of these introductions. The Balearic archipelago is a good example of this, since only two of its current 16 species of reptiles are native. Thirteen years ago, the snake Hemorrhois Hippocrepis was introduced by cargo in Ibiza island, and it is in expansion . Individuals obtained from an early eradication campaign showed a fast expression of phenotypic plasticity and acquired larger sizes than those of the source population, probably due to a high prey availability and predator scarcity. The species is thriving at the expense of a small variety of native and non-native prey, but the predation pressure on the endemic Podarcis pityusensis , the only native reptile in the island, is very high, as this lizard represents 56% of the prey in frequency, which might threaten its survival on the long term. Our results on the feeding ecology of the snake are of sufficient concern to justify the maintenance of actions to eradicate this invader.

  • long and short term impact of temperature on snake detection in the wild further evidence from the snake hemorrhois Hippocrepis
    Acta Herpetologica, 2010
    Co-Authors: Francisco J Zamoracamacho, Gregorio Morenorueda, Juan M Pleguezuelos
    Abstract:

    Global change is causing an average temperature increment which affects several aspects of organisms’ biology, especially in ectotherms. Nevertheless, there is still scant knowledge about how this change is affecting reptiles. This paper shows that, the higher average temperature in a year, the more individuals of the snake Hemorrhois Hippocrepis are found in the field, because temperature increases the snakes’ activity. Furthermore, the quantity of snakes found was also correlated with the temperature of the previous years. Our results suggest that environmental temperature increases the population size of this species, which could benefit from the temperature increment caused by climatic change. However, we did not find an increase in population size with the advance of years, suggesting that other factors have negatively impacted on this species, balancing the effect of increasing temperature.

  • phylogeny biogeography and evolution of two mediterranean snakes malpolon monspessulanus and hemorrhois Hippocrepis squamata colubridae using mtdna sequences
    Molecular Phylogenetics and Evolution, 2006
    Co-Authors: Salvador Carranza, E N Arnold, Juan M Pleguezuelos
    Abstract:

    Variation in 815 bp of mitochondrial DNA from two gene fragments (300 bp of cytochrome b and 395–515 bp of 12S rRNA) for 26 Malpolon monspessulanus, and cytochrome b for a further 21 individuals, indicates that this species originated in the Maghreb area of Northwest Africa. Here, an estimated 3.5–6 Mya, it divided into the western M. m. monspessulanus, and an eastern clade including M. m. insignitus and M. m. fuscus. The very limited genetic differentiation between Maghreb and Southwest European populations of this form suggests that it arrived in the Iberian Peninsula only recently. Population genetics and demographic tests indicate subsequent expansion in this area around 83,000–168,000 year ago. Because present populations of Malpolon arrived recently, mid-Pliocene and at least some Pleistocene fossils of the genus Malpolon in Southwest Europe are probably derived from an earlier invasion from the Maghreb, possibly as early as the end of the Miocene period, 5.3–5.9 Mya, when there was a temporary land bridge across the site of the Strait of Gibraltar and the Mediterranean Sea desiccated. The descendants of this earlier invasion must have eventually become extinct, perhaps during one of the Pleistocene glaciations. In contrast to the western M. m. monspessulanus, the greater genetic divergence found in the eastern clade of M. monspessulanus suggests that it dispersed at an earlier date and probably over a longer period, spreading eastwards through northern Libya and Egypt to Syria, Iraq, and Iran, and around the Mediterranean Sea through Turkey into the Aegean archipelagos and the Balkan peninsula. The western and eastern units of M. monspessulanus have different dorsal color pattern, differences in skull structure and exhibit an 8.4% uncorrected genetic divergence in the combined gene fragments investigated here. It is consequently recommended that they should be treated as separate species: M. monspessulanus (sensu stricto) and Malpolon insignitus stat. nov., the latter including the subspecies Malpolon insignitus fuscus comb. nov. The same combined mitochondrial gene fragments used in Malpolon were investigated in 20 individuals of Hemorrhois Hippocrepis, and of cytochrome b alone in a further 17. They indicate that this species also originated in the Maghreb and again invaded the Iberian Peninsula quite recently. Some of the most recent invasions of the Iberian Peninsula by reptiles and amphibian taxa could probably be anthropogenic in origin. Some other species including M. monspessulanus and H. Hippocrepis, may have crossed naturally, by ‘hopping’ across the Strait of Gibraltar via temporary islands on the shallowest parts that were exposed during sea-level fall associated with Pleistocene glaciations.

Stephen J Wainwright - One of the best experts on this subject based on the ideXlab platform.

  • 3 nitropropionic acid oxidase from horseshoe vetch Hippocrepis comosa a novel plant enzyme
    Biochemical Journal, 1999
    Co-Authors: Charles R Hipkin, Mansour A. Salem, Deborah Simpson, Stephen J Wainwright
    Abstract:

    : A novel enzyme that catalyses the oxygen-dependent oxidation of 3-nitropropionic acid (3NPA) to malonate semialdehyde, nitrate, nitrite and H2O2 has been purified from leaf extracts of the horseshoe vetch, Hippocrepis comosa, and named 3NPA oxidase. The enzyme is a flavoprotein with a subunit molecular mass of 36 kDa containing 1 molecule of FMN and exhibits little specificity for all nitroalkanes tested other than 3NPA (apparent Km 620 microM). The maximum enzyme activity in vitro was expressed at pH4.8 and was inhibited strongly by the products nitrate and nitrite. 3NPA oxidase activity was detected in green shoots, which also contain high concentrations of 3NPA, from plants grown with nitrate, ammonium or N2 as sources of nitrogen. Enzyme activity was absent from roots and cell cultures, neither of which accumulate high levels of 3NPA.

  • nitroaliphatic compounds in Hippocrepis comosa and other legumes in the european flora
    Phytochemistry, 1995
    Co-Authors: Mansour A. Salem, Michael J Williams, Stephen J Wainwright, Charles R Hipkin
    Abstract:

    Abstract In a survey of 148, mostly European, angiosperm species, 3-nitropropionate was found only in extracts of the legumes, Hippocrepis balearica, H. comosa, Lotus uliginosus and Scorpiurus muricatus . Three separate nitropropanoyl esters of glucose, 6-(3-nitropropanoyl)-αβ- d -glucopyranose, 1,6- di -O-(3- nitropropanoyl -β- d - glucopyranose (cibarian) and 1,2,6- tri -O-(3- nitropropanoyl )-β- d - glucopyranose (karakin) were identified in shoot extracts of H . comosa . Evidence for the presence of the 3-nitropropanoyl ester of 4-hydroxybutanoic acid in extracts of H . comosa is also presented.

Charles R Hipkin - One of the best experts on this subject based on the ideXlab platform.

  • 3 nitropropionic acid oxidase from horseshoe vetch Hippocrepis comosa a novel plant enzyme
    Biochemical Journal, 1999
    Co-Authors: Charles R Hipkin, Mansour A. Salem, Deborah Simpson, Stephen J Wainwright
    Abstract:

    : A novel enzyme that catalyses the oxygen-dependent oxidation of 3-nitropropionic acid (3NPA) to malonate semialdehyde, nitrate, nitrite and H2O2 has been purified from leaf extracts of the horseshoe vetch, Hippocrepis comosa, and named 3NPA oxidase. The enzyme is a flavoprotein with a subunit molecular mass of 36 kDa containing 1 molecule of FMN and exhibits little specificity for all nitroalkanes tested other than 3NPA (apparent Km 620 microM). The maximum enzyme activity in vitro was expressed at pH4.8 and was inhibited strongly by the products nitrate and nitrite. 3NPA oxidase activity was detected in green shoots, which also contain high concentrations of 3NPA, from plants grown with nitrate, ammonium or N2 as sources of nitrogen. Enzyme activity was absent from roots and cell cultures, neither of which accumulate high levels of 3NPA.

  • nitroaliphatic compounds in Hippocrepis comosa and other legumes in the european flora
    Phytochemistry, 1995
    Co-Authors: Mansour A. Salem, Michael J Williams, Stephen J Wainwright, Charles R Hipkin
    Abstract:

    Abstract In a survey of 148, mostly European, angiosperm species, 3-nitropropionate was found only in extracts of the legumes, Hippocrepis balearica, H. comosa, Lotus uliginosus and Scorpiurus muricatus . Three separate nitropropanoyl esters of glucose, 6-(3-nitropropanoyl)-αβ- d -glucopyranose, 1,6- di -O-(3- nitropropanoyl -β- d - glucopyranose (cibarian) and 1,2,6- tri -O-(3- nitropropanoyl )-β- d - glucopyranose (karakin) were identified in shoot extracts of H . comosa . Evidence for the presence of the 3-nitropropanoyl ester of 4-hydroxybutanoic acid in extracts of H . comosa is also presented.

Thomas Kuchler - One of the best experts on this subject based on the ideXlab platform.

  • Upper Cretaceous of the Barranca (Navarra, northern Spain); integrated litho-, bio- and event stratigraphy. Part II: Campanian and Maastrichtian
    Acta Geologica Polonica, 2020
    Co-Authors: Thomas Kuchler
    Abstract:

    Campanian to Lower Maastrichtian strata of the eastern Barranca (Navarra, northern Spain), based on 11 exposures near Irurzun, were investigated in detail and correlated with coeval strata of the western Barranca and the Oroz-Betelu Massif (Navarra). The Sarasate Formation exposed in the Barranca is divided into ten members. Deposition was influenced by uplift of the Anoz-Ollo salt structure during the latest Santonian and Early Campanian. The Campanian – Maastrichtian of Navarra is characterised by thick and relatively complete successions containing biostratigraphically significant fossil groups (ammonites, inoceramids, echinoids). Detailed bed-by-bed collecting has enabled the establishment of an integrated zonal scheme with potential for interbasinal correlation. In addition to local peak, partial range and assemblage zones, based on echinoids and ammonite – echinoid assemblages, an ammonite zonation, based on an unnamed interval and the following 10 partial range (PRZ) and assemblage zones (AZ) of Scaphites Hippocrepis III, S. Hippocrepis  III/ Menabites spp., Hoplitoplacenticeras marroti , Trachyscaphites spiniger , Pseudoxybeloceras phaleratum ,  Nostoceras ( Bostrychoceras ) polyplocum , Trachyscaphites pulcherrimus , N . ( Didymoceras ) archiacianum ,  N . ( Nostoceras ) hyatti , and Pachydiscus neubergicus / Pachydiscus epiplectus , is presented. The ammonite zonation markedly refines both the existing regional and the so-called European standard zonal schemes. Correlation with other Spanish areas (Cantabria, Burgos and Guipuzcoa), the Aquitaine (France), Westphalia and Lower Saxony (Germany) and the Vistula valley (Poland) is discussed. Twelve of the recognised bio-events, characterised by mass-occurrences of irregular echinoids and of monospecific, or taxonomically more variable, mostly heteromorph ammonite assemblages, are significant for regional correlation. Three Offaster maxima are of interbasinal importance as they can be correlated to Germany, Great Britain and Northern Ireland. The origin of these bio-events is closely related to the transgressive and regressive pulses recognised in Navarra, of which the pomeli Transgression I and the Hippocrepis , subglobosa  and polyplocum regressions are the most pronounced. The tectonic phase at the Santonian/Campanian boundary is related to the Wernigerode Phase. The onset of the second phase is placed in the lower Upper Campanian marroti Zone, the onset of a third phase (UCTE) in the upper Upper Campanian polyplocum  Zone.

  • Scaphites Hippocrepis (DEKAY) IV, a new chronological subspecies from the Lower – Upper Campanian (Upper Cretaceous) boundary interval of northern Spain
    Acta Geologica Polonica, 2020
    Co-Authors: Thomas Kuchler
    Abstract:

    A fourth chronological subspecies of Scaphites Hippocrepis (DEKAY), called S. Hippocrepis IV, is described from the highest Lower Campanian and lower Upper Campanian of Navarra, northern Spain. It is the stratigraphically highest representative of the Hippocrepis lineage, characterized by strong conical to massive umbilical tubercles, which number three to five in microconchs and five in macroconchs.

  • scaphites Hippocrepis dekay iv a new chronological subspecies from the lower upper campanian upper cretaceous boundary interval of northern spain
    Acta Geologica Polonica, 2000
    Co-Authors: Thomas Kuchler
    Abstract:

    A fourth chronological subspecies of Scaphites Hippocrepis (DEKAY), called S. Hippocrepis IV, is described from the highest Lower Campanian and lower Upper Campanian of Navarra, northern Spain. It is the stratigraphically highest representative of the Hippocrepis lineage, characterized by strong conical to massive umbilical tubercles, which number three to five in microconchs and five in macroconchs.

Honor C Prentice - One of the best experts on this subject based on the ideXlab platform.