Analysis of threats to South American flora and its implications for conservation

Diversity and Conservation Gap Analysis of the Solanaceae of Southern South America

There is a need to make substantial advances in the taxonomic, systematic, and distribution knowledge of plants, and find better ways of transmission of this information to society to surpass the general pattern described as "plant blindness." The diversity of the plant family Solanaceae reaches its peak in South America; however, many of its species are threatened due to the expansion of the human footprint. Here, we examine the diversity patterns of the family in southern South America (Argentina and Chile) by means of species richness (SR), weighted endemism (WE), and corrected weighted endemism (CWE). We also evaluated conservation gaps in relation to protected areas and the human footprint as a proxy for potential impacts on this biodiversity. Results show two richness centers in NW and NE Argentina, with a high degree of overlap with protected areas, which, on the other side, show a relative high index of human footprint. Comparatively, coastal Atacama (Chile) shows lower richness values, but outstanding CWE and WE values. The coast of Atacama harbors high values due the presence of species of the genus Nolana with restricted distributions. Protected areas in this tight coastal strip are sparse, and the human footprint is also relatively high. The degree of protection based on these parameters is then unbalanced, highlighting the need for a geographically explicit strategy for the conservation of the family at subcontinental scale. In doing so, it is likely that other representatives of these unique centers of richness and endemism will benefit.

Diversity of Myrtaceae in and surroundings the Chapada Diamantina National Park, Brazil

Abstract We evaluated the diversity of Myrtaceae in Chapada Diamantina National Park (CDNP) and neighboring municipalities (NM), identifying the areas with the highest richness and those with the lowest sampling efforts, collecting specimens in situ, and analyzing herbarium collections. The geographic data and maps include collection efforts (CE), species richness (SR), and estimated richness (J1). Ninety-seven species and nine genera were recorded for NM, with 82 species and nine genera occurring in CDNP. The CE and SR were similar in NM and CDNP, and the quadrants with the highest values were in the municipalities of Lençóis and Palmeiras. The J1 was also similar in NM and CDNP. Fifteen species found in NM do not occur in CDNP, and some are considered endangered or are restricted to non-protected areas, especially caatinga areas. Some species showed distributions limited to only one or two vegetation types, although many areas have been only superficially surveyed. Endemic species are subject to anthropic pressure, and some are currently considered endangered or vulnerable. The expansion of the limits of the CDNP to encompass areas of caatinga vegetation will improve the conservation status of the family.

Synopsis of the genus Ponthieva (Orchidaceae) in Colombia

The Neotropical orchid genus Ponthieva R. Br. was established in 1813. The 70 representatives of this taxon are terrestrial, lithophytic, or epiphytic plants with basal, sessile, or petiolate leaves which are glabrous or pubescent. Their erect peduncle is pubescent and terminated by lax, few- to many-flowered raceme. Flowers are non-resupinate, with dissimilar sepals and asymmetrical petals which are adnate to the sides of the gynostemium. The lip is uppermost, fused to the lower part of the gynostemium. Here the synopsis of Colombian Ponthieva is presented. A list of national genus representatives includes 26 species, including one new species, P. vallecaucana Szlach. Kolan. & Olędrzyńska, sp. nov., discovered during this study. We did not confirm occurrence of four species reported in previous research. To facilitate process of identification of genus representatives, we divided Ponthieva into six morphological complexes based on vegetative and floral characters. The highest number of species was found in Magdalena and Cauca Valley montane forests. Lectotypes for Ponthieva inaudita and P. mandonii are designated. Morphological characteristics and illustrations of perianth segments of Colombian representatives of the genus are provided as well as a key for their identification.

Genetically informed ecological niche models improve climate change predictions

We examined the hypothesis that ecological niche models (ENMs) more accurately predict species distributions when they incorporate information on population genetic structure, and concomitantly, local adaptation. Local adaptation is common in species that span a range of environmental gradients (e.g., soils and climate). Moreover, common garden studies have demonstrated a covariance between neutral markers and functional traits associated with a species' ability to adapt to environmental change. We therefore predicted that genetically distinct populations would respond differently to climate change, resulting in predicted distributions with little overlap. To test whether genetic information improves our ability to predict a species' niche space, we created genetically informed ecological niche models (gENMs) using Populus fremontii (Salicaceae), a widespread tree species in which prior common garden experiments demonstrate strong evidence for local adaptation. Four major findings emerged: (i) gENMs predicted population occurrences with up to 12-fold greater accuracy than models without genetic information; (ii) tests of niche similarity revealed that three ecotypes, identified on the basis of neutral genetic markers and locally adapted populations, are associated with differences in climate; (iii) our forecasts indicate that ongoing climate change will likely shift these ecotypes further apart in geographic space, resulting in greater niche divergence; (iv) ecotypes that currently exhibit the largest geographic distribution and niche breadth appear to be buffered the most from climate change. As diverse agents of selection shape genetic variability and structure within species, we argue that gENMs will lead to more accurate predictions of species distributions under climate change.

Incorporating climate change and exotic species into forecasts of riparian forest distribution

We examined the impact climate change (CC) will have on the availability of climatically suitable habitat for three native and one exotic riparian species. Due to its increasing prevalence in arid regions throughout the western US, we predicted that an exotic species, Tamarix, would have the greatest increase in suitable habitat relative to native counterparts under CC. We used an ecological niche model to predict range shifts of Populus fremontii, Salix gooddingii, Salix exigua and Tamarix, from present day to 2080s, under five general circulation models and one climate change scenario (A1B). Four major findings emerged. 1) Contrary to our original hypothesis, P. fremontii is projected to have the greatest increase in suitable habitat under CC, followed closely by Tamarix. 2) Of the native species, S. gooddingii and S. exigua showed the greatest loss in predicted suitable habitat due to CC. 3) Nearly 80 percent of future P. fremontii and Salix habitat is predicted to be affected by either CC or Tamarix by the 2080s. 4) By the 2080s, 20 percent of S. gooddingii habitat is projected to be affected by both Tamarix and CC concurrently, followed by S. exigua (19 percent) and P. fremontii (13 percent). In summary, while climate change alone will negatively impact both native willow species, Tamarix is likely to affect a larger portion of all three native species' distributions. We discuss these and other results in the context of prioritizing restoration and conservation efforts to optimize future productivity and biodiversity. As we are accounting for only direct effects of CC and Tamarix on native habitat, we present a possible hierarchy of effects- from the direct to the indirect- and discuss the potential for the indirect to outweigh the direct effects. Our results highlight the need to account for simultaneous challenges in the face of CC.

Red List assessments of East African chameleons: a case study of why we need experts

The IUCN Red List of Threatened Species uses geographical distribution as a key criterion in assessing the conservation status of species. Accurate knowledge of a species’ distribution is therefore essential to ensure the correct categorization is applied. Here we compare the geographical distribution of 35 species of chameleons endemic to East Africa, using data from the Global Biodiversity Information Facility (GBIF) and data compiled by a taxonomic expert. Data screening showed 99.9% of GBIF records used outdated taxonomy and 20% had no locality coordinates. Conversely the expert dataset used 100% up-to-date taxonomy and only seven records (3%) had no coordinates. Both datasets were used to generate range maps for each species, which were then used in preliminary Red List categorization. There was disparity in the categories of 10 species, with eight being assigned a lower threat category based on GBIF data compared with expert data, and the other two assigned a higher category. Our results suggest that before conducting desktop assessments of the threatened status of species, aggregated museum locality data should be vetted against current taxonomy and localities should be verified. We conclude that available online databases are not an adequate substitute for taxonomic experts in assessing the threatened status of species and that Red List assessments may be compromised unless this extra step of verification is carried out.