Miniaturization during a Silurian environmental crisis generated the modern brittle star body plan

Pivotal anatomical innovations often seem to appear by chance when viewed through the lens of the fossil record. As a consequence, specific driving forces behind the origination of major organismal clades generally remain speculative. Here, we present a rare exception to this axiom by constraining the appearance of a diverse animal group (the living Ophiuroidea) to a single speciation event rather than hypothetical ancestors. Fossils belonging to a new pair of temporally consecutive species of brittle stars (Ophiopetagno paicei gen. et sp. nov. and Muldaster haakei gen. et sp. nov.) from the Silurian (444–419 Mya) of Sweden reveal a process of miniaturization that temporally coincides with a global extinction and environmental perturbation known as the Mulde Event. The reduction in size from O. paicei to M. haakei forced a structural simplification of the ophiuroid skeleton through ontogenetic retention of juvenile traits, thereby generating the modern brittle star bauplan.

Risks and opportunities of assisted colonization: the perspectives of experts

Owing to climate change and other anthropogenic environmental changes, the suitability of locations is changing for many biota that consequently have to adapt in situ or to move to other areas. To mitigate the effects of such pressures, assisted colonization is a conservation tool developed to reduce extinction risks by intentionally moving and releasing an organism outside its native range, and thus, to facilitate tracking changing environmental conditions. This conservation tool has been proposed for threatened animals or plants that presumably cannot adapt in situ or follow environmental changes by dispersal or migration. However, there have been contentious debates about the shortcomings and risks of implementing assisted colonization. For this reason, we evaluated the specific opinions of global experts for assisted colonization on potential risks and opportunities that this approach offers. For this purpose, we used an online survey targeted at authors of scientific publications on assisted colonization. The majority (82%) of the 48 respondents were in favor of applying assisted colonization for species that are at risk of global extinction due to anthropogenic environmental change. Most respondents agreed that assisted colonization should be considered only when other conservation tools are not available and that certain preconditions must be met. Some of these were already highlighted in the IUCN guidelines for assisted colonization and include a completed risk assessment, clearly defined management plans and secured political as well as financial support. The advocacy of assisted colonization in response to anthropogenic global environmental changes was only weakly dependent on the geographic origin of the experts and their working background. Regarding possible risks, most of the respondents were concerned about consequences like failure of the long-term establishment of the translocated species and the transmission of diseases and invasiveness potentially endangering native biota. To keep these risks as low as possible most of the experts agreed that a target area must have a reasonable carrying capacity to sustain a minimum viable population and that adaptive management should be implemented. Careful evaluation of assisted colonization projects is required to generate further evidence that needs to be considered for further developing conservation tools for the Anthropocene.

EVALUATING CONSERVATION STATUS, THREATS AND POPULATION TRENDS OF LEUCADENDRON, A PLANT GENUS ENDEMIC TO THE CAPE REGION IN SOUTH AFRICA

Declines in endemic species have significant impact on global biodiversity loss. More efforts need to be harnessed to further protect endemic species from the current global extinction crisis. This study evaluated the current conservation status, factors responsible for risk of extinction and the trends in populations of Leucadendron, a plant genus endemic to the Cape region in South Africa. The SANBI (South African National Biodiversity Institute) Red List was employed in this study. The results revealed that over 50% of taxa in this genus are threatened and most of the species are exposed to habitat destruction and the presence of invasive species. It was also discovered that two species of this genus are currently extinct, which implies this genus is facing a high risk of extinction. More efforts, such as designing effective methods of controlling forces responsible for the risk of extinction of taxa in this genus, should be put in place to prevent their complete extirpation in future.

Birds of the Pantanal floodplains, Brazil: historical data, diversity, and conservation

The Pantanal floodplains of Brazil are a region of rich biodiversity. To date, the true richness of the Pantanal avifauna has not been explored satisfactorily caused by a lack of studies in the region and, especially, by the divergence of opinion among the works published by various authors on the many species found in the region. This is due to the lack of criteria in examining records, both with regard to the reliability of the identifications and in the precise geographical allocation. Therefore, in the study, we collage findings from various studies and records created by us in the last few decades from 199 distinct locations to produce a list of birds in the Pantanal floodplains. We grouped the results into three lists: primary, secondary, and tertiary. We found that the avifauna of the Pantanal floodplain is composed of a total of 617 species, of which 571 (92%) have supporting records of occurrence (primary list) and 46 still lack documentation (secondary list). The number of species listed here for the Pantanal floodplain represents 32% of all avifauna known to the Brazilian territory. This reflects the importance of the biome, as part of the national territory, for the maintenance of a meaningful avifaunistic richness. Migratory birds (n = 183), notably northern ones (n = 43), are among the main players involved in ecological processes of nutrient cycling and dispersion of important pathogens between the two continents. With regard to conservation, 25 species are included in some category of threat in the lists of threatened species with global extinction. We hope that our list will help future researchers a more definitive approach when researching the avian fauna in this bountiful region.

Buran Nalgarra: an Indigenous-led model for walking with good spirit and learning together on Darug Ngurra

In the distressing midst of global extinction and environmental crises, changes to the ways that places are managed and cared for are vital and urgent. We offer here an Indigenous-led model of cross-cultural collaboration based on lessons shared by Darug custodians in Sydney, Australia, embedded in the making of buran nalgarra (stringybark rope). The Buran Nalgarra model of collaboration is not a simple cut-and-paste model nor panacea for effective collaboration. Rather, embedded deeply in Darug Ngurra (Darug Country), we share what we have learnt and value through our Caring-as-Darug-Ngurra project in the hope that others will find our guiding principles and processes useful, and perhaps adapt our learning to their own places. We strive for strength and learning through togetherness.

Pseudohydrosme bogneri sp. nov. (Araceae), a spectacular Critically Endangered (Possibly Extinct) species from Gabon, long confused with Anchomanes nigritianus

SummaryA Gabonese taxon cultivated for decades in the botanic gardens of Europe as Anchomanes nigritianus is shown to be a new species to science, and on current evidence, is best placed as the fourth species of the Gabonese-centred, poorly known genus Pseudohydrosme. Data on the morphological separation between Anchomanes and Pseudohydrosme are reviewed. Although phylogenomic studies may show in future that the two genera need to be merged, for the moment their separation is reinforced on morphological grounds. Anchomanes lacks the spathe tube, ovoid-globose, 2 – 4 locular pistil and thick, lobed stigma on a symmetric, stout style that we show to characterise the redelimited Pseudohydrosme. (Anchomanes has oblong, polygonal, 1-locular pistils, stigmas asymmetric, sessile, thin and disc-like or on asymmetrical conical styles and are pointed or brush-like). In addition, Pseudohydrosme (where known) has stipitate (versus sessile) fruits and on current evidence lacks the lacticifers recorded from Anchomanes. We test the hypothesis that the taxon is a new species to science, naming it as Pseudohydrosme bogneri, and conclude that it is Critically Endangered (Possibly Extinct) using the IUCN 2012 standard. Pseudohydrosme bogneri appears to be the tenth documented probable global extinction of a plant species that has occurred among the narrowly endemic plant species of the Libreville area, Gabon.