Germination requirements of Plantago algarbiensis seeds, an endangered species endemic to the Algarve region (South of Portugal)

The ecdysteroid, 20-hydroxyecdysone or beta-ecdysone, is a steroid hormone which plays a crucial role in molting, metamor- phosis and reproduction of arthropods. This ecdysteroid and its analogues have high potential to be used as insecticides. Previous studies in our laboratory have demonstrated that Vitex glabrata R.Br. (commonly known as Khai-Nao), an indigenous herbaceous plant of Thailand, synthesized and accumulated high quantity of 20-hydroxyecdysone. Therefore, the aim of this study was to investigate the effect of precursor and elicitors feeding on cell growth and 20-hydroxyecdysone production of V. glabrata suspension cultures. Plant cells were cultured in half strength MS medium containing 30 g/l glucose and supplemented with 2.0 mg/l 6- benzylaminopurine (BAP) and 1.0 mg/l 2,4-dichlorophenoxyacetic acid (2,4-D). Cells were incubated on a rotary shaker at 120 rpm under continuous light of 2000 lux at 25 °C. Sterilized cholesterol (5 and 10 mg/l) as precursor was added to the cell cultures on the day of inoculation, while chitosan (50, 100 and 200 mg/l) and methyl jusmonate (100 and 200 mM) as elicitors were added to the cell cultures on day 6 after cultivation.

Status and the potential for extinction of the largetooth sawfish Pristis pristis in the Atlantic Ocean

1. Sawfishes currently are among the most threatened elasmobranchs in the world. Only two species inhabit Atlantic waters: the largetooth sawfish (Pristis pristis) and the smalltooth sawfish (Pristis pectinata), both having suffered dramatic declines in their ranges. 2. The goal of this study was to evaluate the status of P. pristis in the Atlantic, and estimate local extinction risk based on historical and recent occurrence records. In order to accomplish these goals, a thorough search for historical and recent records of P. pristis in the Atlantic was conducted, by reviewing scientific and popular literature, museum specimens, and contacting regional scientists from the species’ historical range. 3. In total, 801 P. pristis records (1830–2009) document its occurrence in four major regions in the Atlantic: USA (n =41), Mexico and Central America (n =535), South America (n=162), and West Africa (n =48). Locality data were not available for 15 records. 4. Historical abundance centres were the Colorado-San Juan River system in Nicaragua and Costa Rica (and secondarily Lake Izabal of Guatemala), the Amazon estuary, and coastal Guinea-Bissau. 5. Currently, the species faces drastic depletion throughout its entire former range and centres of abundance. It appears to have been extirpated from several areas. The probability of extinction was highest in the USA, northern South America (Colombia to Guyane), and southern West Africa (Cameroon to Namibia). 6. Currently, the Amazon estuary appears to have the highest remaining abundance of P. pristis in the Atlantic, followed by the Colorado–San Juan River system in Nicaragua and Costa Rica and the Bissagos Archipelago in Guinea Bissau. Therefore the protection of these populations is crucial for the preservation and recovery of the species.

Can we use niche models of indicator species to predict the distribution of endangered communities?

European-wide conservation policies are based on the identification of priority habitats. However, research on conservation biogeography often relies on the results and projections of species distribution models to assess species' vulnerability to global change. We assess whether the distribution and structure of threatened communities can be predicted by the suitability of the environmental conditions for their indicator species. We present some preliminary results elucidating if using species distribution models of indicator species at a regional scale is a valid approach to predict these endangered communities. Dune plant assemblages, affected by severe conditions, are excellent models for studying possible interactions among their integrating species and the environment. We use data from an extensive survey of xerophytic inland sand dune scrub communities from Portugal, one of the most threatened habitat types of Europe. We identify indicator shrub species of different types of communities, model their geographical response to the environment, and evaluate whether the output of these niche models are able to predict the distribution of each type of community in a different region.

Using niche modelling of indicator species to predict the distribution of xerophitic shrub dune communities in South-Western Portugal

Inland sand dune systems are amongst the most threatened habitat types of Europe. Affected by severe conditions, these habitats present distinct community compositions, which makes them excellent for studying possible interactions among their integrating species and the environment. We focus on understanding the distribution and cooccurrence of the species from dune plant assemblages as a key step for the adequate protection of these habitats. Using data from an extensive survey we identified the shrub species that could be considered indicators of the different xerophytic scrub dune communities in South West Portugal. Then, we modelled the responses of these species to the environmental conditions using Ecological Niche Factor Analysis. We present some preliminary results elucidating whether using species distribution models of indicator species at a regional scale is a valid approach to predict the distribution of the different types of communities inhabiting these endangered habitats.