High-resolution topographic variables accurately predict the distribution of rare plant species for conservation area selection in a narrow-endemism hotspot in New Caledonia

Species distribution models (SDMs) represent a widely acknowledged tool to identify priority areas on the basis of occurrence data and environmental factors. However, high levels of topographical and climatic micro-variation are a hindrance to reliably modelling the distribution of narrow-endemic species when based on classic occurrence and climate datasets. Here, we used high-resolution environmental variables and occurrence data obtained from dedicated field studies to produce accurate SDMs at a local scale. We modelled the potential current distribution of 23 of the 25 rarest species from Mount Kaala, a hotspot of narrow-endemism in New Caledonia, using occurrence data from two recent sampling campaigns, and eight high-resolution (10 m and 30 m) environmental predictors in a Species Distribution Modelling framework. After a first sampling operation, we surveyed six additional areas containing, overall, 13 of the 20 species modelled at this stage, to validate our projections where the highest species richness levels were predicted. The ability of our method to define conservation areas was largely validated with an average 84% of predicted species found in the validation areas, and additional data collected enabling us to model three more species. We therefore identified the areas of highest conservation value for the whole of Mount Kaala. Our results support the ability of SDMs based on presence-only data such as MaxEnt to predict areas of high conservation value using fine-resolution environmental layers and field-collected occurrence data in the context of small and heterogeneous systems such as tropical islands.

Discovery of the chelonine tribe Adeliini Viereck, 1918 (Hymenoptera: Braconidae) from the Indian subcontinent with the description of a new genus from south India

The small chelonine tribe Adeliini is one of the derived groups with the postpectal carina absent, which is considered to be an apomorphic character for the Cheloninae. Adeliine genera generally exhibit a narrow endemism although the genus Adelius is widely distributed. Adeliini are reported from the Indian subcontinent for the first time with the description of a new genus and a new species, Carinadelius medicus Ranjith & van Achterberg gen. et sp. nov. from south India. A revised key to the genera of Adeliini is provided with the illustrations of all included genera. The genus Myriola, which was previously included under Adelius, is re-instated based on morphological characters. The New World species of the genus Paradelius are transferred to Sculptomyriola Belokobylskij: Sculptomyriola neotropicalis (Shimbori & Shaw, 2019), S. nigra (Whitfield, 1988) and S. rubra (Whitfield, 1988) are new combinations.

Hotspots of narrow endemisms: adequate focal points for conservation in Dendrochilum (Orchidaceae)

The general aim of conservation is to ensure persi- stence of biodiversity value. Given certain measures (financial, logistic, etc.) the specific goal must be to maximize the amount of biodiversity value to be secured by these means. Several area selection met- hods are available for such purpose, and they repres- ent very different conservation philosophies (Williams et al. 1996; Humphries 2006). Two funda- mentally different approaches exist: (1) locating hot- spots of species richness or narrow endemism, and (2) designating conservation areas according to com- plementarity methods.

DIVERSITY OF BEGONIA (BEGONIACEAE) IN BORNEO – HOW MANY SPECIES ARE THERE?

A total of 126 species are currently named and described from Borneo (Brunei - 16 species, Kalimantan – 5 species, Sabah – 41 species and Sarawak – 72 species). However, based on our survey of the begonia collection in the Sarawak Herbarium, the un-named taxa (about 110 species) significantly outnumber the 72-named species. The situation is probably the same for Sabah, so with many more new species than the 41 named ones at a conservative estimate the Sabah begonia flora can be expected to exceed 100 species. For Kalimantan (5 named species), the total number of un-named species is likely to be even higher considering that Kalimantan occupies a larger land area, its begonia-rich mountains and limestone areas are hardly collected, and the begonia flora has hardly been studied at all. We can therefore expect the begonia flora of Borneo to exceed 600 species. In view of the high level of narrow endemism (80% of species are known from a single locality), expeditions to unexplored areas are necessary to document, in particular, areas that are experiencing irreversible land-use change. Alpha-taxonomy on a large scale is needed to tackle the backlog of literally hundreds of new undescribed species.

Areas of endemism of Cactaceae and the effectiveness of the protected area network in the Chihuahuan Desert

We used distribution data of 121 cactus species endemic to the Chihuahuan Desert to test the effectiveness of the region’s protected area network. The analysis of species distribution using a 30′ latitude × 30′ longitude grid facilitated the identification and categorization of areas of endemism. We found a low degree of coincidence between protected areas and the areas of cactus endemism, and only 63.6% of the 121 species occur in protected areas. A complementarity analysis showed that 10 of the protected areas contain the 77 species that occur in protected areas. The four top priority areas protect 65 (84.4%) of these 77 species The 44 unprotected species are mainly micro-endemic and taxonomically distinctive taxa widely scattered in the region. The complementarity analysis applied to these species showed that all of them can be contained in a minimum of 24 grid squares, representing 32.9% of the total area occupied. Their strong spatial dispersion, along with their narrow endemism, is a major conservation challenge. We conclude that the current protected area network is insufficient to protect the rich assemblage of cacti endemic to the Chihuahuan Desert. Conservation efforts in this region should be enhanced by increasing the effectiveness of the already existing protected areas and by the creation of additional protected areas, specifically micro-reserves, to provide refuge for the unprotected species.