Distribution models and species discovery: the story of a new Solanum species from the Peruvian Andes

Geographic distribution, conservation status and lectotypification of Pedersenia weberbaueri (Suess.) Holub (Amaranthaceae), an endemic and highly threatened shrub from the Marañón valley of Peru

The present study analyses the geographical distribution, conservation status, and nomenclature of Peruvian endemic Pedersenia weberbaueri. The species distribution was modelled using MaxEnt based on occurrence data and bioclimatic variables. The conservation status of the species was assessed against the categories and criteria of the IUCN Red List, and nomenclatural and typification issues were resolved. The potential distribution map of P. weberbaueri shows that the species is restricted to the seasonally dry tropical forests of the Marañón valley within a narrow latitudinal, longitudinal, and elevational range. Consequently, we propose to categorise the species as Endangered (EN) and provide the necessary information for its inclusion in the IUCN Red List. Finally, we resolve nomenclatural issues and designate a lectotype. The results contribute to the biological knowledge of P. weberbaueri and support subsequent conservation management plans.

Phylogeny and biogeography of the Daniellia clade (Leguminosae: Detarioideae), a tropical tree lineage largely threatened in Africa and Madagascar

The legume subfamily Detarioideae is exceptionally diverse in tropical Africa and Madagascar, compared to South America or Asia, a trend contrary to that shown by most other pantropical plant groups. We aim to elucidate the process of diversification giving rise to these high diversity levels by focussing our investigations on the Daniellia clade, which is present in both Africa and Madagascar. The Daniellia clade is an early-diverging lineage of subfamily Detarioideae (Leguminosae; pea family) and consists of three genera: Daniellia, Brandzeia and Neoapaloxylon. The species belonging to this group exhibit a wide range of habitat types. The Madagascar endemics Brandzeia (1 species) and Neoapaloxylon (3 species) occupy dry woodlands and arid succulent habitats respectively. Daniellia alsteeniana and D. oliveri are found in savannahs while the remaining eight species within Daniellia all occupy rainforest habitats. Phylogenetic analyses were generated from a dense, multi-individual species level sampling of the clade. Divergence time estimates were carried out using a molecular clock method to investigate biogeographical patterns and shifts in habitat types within the Daniellia clade, and conservation assessments were conducted to determine the levels of extinction risks these species are facing. We estimate that the Daniellia clade first emerged during the Early Eocene from an ancestor present in the rainforests of North Africa at that time, reflecting an ancestral habitat preference. There was a first major split over the course of the Eocene, giving rise to both African rainforest and Madagascan savannah lineages. With the emergence of a drier climate and vegetation type in Africa during the Eocene, it is likely that a dry-climate adapted lineage from the Daniellia clade ancestor could have dispersed through suitable savannah or woodland regions to reach Madagascar, subsequently giving rise to the savannah-adapted ancestor of Brandzeia and Neoapaloxylon in the Early Miocene. The African rainforest lineage gave rise to the genus Daniellia, which is postulated to have first diversified in the Middle Miocene, while savannah species of Daniellia emerged independently during the Pliocene, coinciding with the global rise of C4-dominated grasslands. More than half of the species in the Daniellia clade are near threatened or threatened, which highlights the need to understand the threats of anthropogenic pressures and climate change these species are facing to prioritise their conservation.

A new black nightshade (Morelloid clade, Solanum, Solanaceae) from the caatinga biome of north-eastern Brazil with a key to Brazilian morelloids

Solanumcaatingae sp. nov. is described from the arid caatinga biome of north-eastern Brazil. It is known from only a few specimens, but these were found amongst the many sheets of the widespread circumtropical weed S.americanum Mill.; it is possible that more will be found once its distinct nature has been recognised. It differs from S.americanum and all other herbaceous black nightshades known in Brazil, in its combination of glandular pubescence and shiny black fruit with small spreading sepals. The description of S.caatingae brings the number of morelloid solanums in Brazil to seven and a key is provided for their identification.

Two new non-spiny Solanum (Solanaceae) from the Gran Chaco Americano and a key for the herbaceous glandular-pubescent solanums from the region

The Gran Chaco Americano is a major savanna woodland system in South America that harbours great plant and animal diversity. Two new herbaceous species of the Morelloid clade of Solanum (largely corresponding to the traditional Solanum section Solanum) are described here from the Bolivian Chaco. Both species are morphologically similar to a group of related species with glandular pubescence and enlarged, foliaceous calyces that includes Solanum atriplicifolium Gillies ex Nees, Solanum nitidibaccatum Bitter, Solanum physalifolium Rusby, Solanum sarrachoides Sendtn. and Solanum tweedianum Hook. Solanum woodii Särkinen & S.Knapp, sp. nov. is unusual in the Morelloid clade in having tapering anthers on short filaments, and is superficially similar to the unrelated Solanum anomalostemon S.Knapp & M.Nee from dry forests in Peru. Solanum michaelis Särkinen & S.Knapp, sp. nov. is distinct in its enlarged calyx with a short tube and long lobes that apparently reflex at fruit maturity. Both new taxa are illustrated, their conservation status assessed, and their distributions mapped. We also provide a key to the glandular-pubescent herbaceous Solanum species of the Chaco vegetation to aid in identification of these taxa.

Two new non-spiny Solanum species from the Bolivian Andes (Morelloid Clade)

Two new Bolivian species are described from the Morelloid clade of Solanum (section Solanum in the traditional sense). Solanumalliariifolium M.Nee & Särkinen, sp. nov. is found in montane forests between 1,900 and 3,200 m and is morphologically most similar to Solanumleptocaulon Van Heurck & Müll.Arg., also from montane forests in southern Peru and Bolivia. Solanumrhizomatum Särkinen & M.Nee, sp. nov. is found in seasonally dry forests and matorral vegetation in lower elevations between 1,300 and 2,900 m and is most similar to Solanumpygmaeum Cav., a species native to sub-tropical Argentina but introduced in subtropical and temperate areas worldwide.

Four new non-spiny Solanum (Solanaceae) species from South America

Four new species of "non-spiny" Solanum from South America are described. Solanumlongifilamentum Särkinen & P.Gonzáles, sp. nov. (Morelloid clade) is widespread from Ecuador to Bolivia and is most similar to Solanummacrotonum Dunal from Central and northern South America. Solanumantisuyo Särkinen & S.Knapp, sp. nov. (Morelloid clade) is found on the eastern Andean slopes in Ecuador, Peru and Bolivia and is most similar to the widespread lower elevation species Solanumpolytrichostylum Bitter. Solanumarenicola Särkinen & P.Gonzáles, sp. nov. (Morelloid clade) is found in low elevation habitats on the eastern Andean slopes and in Amazonia of Peru and Bolivia and is most similar to the higher elevation species Solanumaloysiifolium Dunal of Bolivia and Argentina. Solanummariae Särkinen & S.Knapp, sp. nov. (Potato clade) is endemic to Cajamarca Department in Peru, and is most similar to the widespread Solanumcaripense Dunal. Complete descriptions, distributions and preliminary conservation assessments of all new species are given.

A new species of spiny Solanum (Solanaceae) from Peru

A new species of Solanum is described from Peru. Solanum junctum S. Stern & M. Nee, sp nov. is a member of the Torva clade of the spiny solanums (Leptostemonum clade). The narrow corolla lobes and recurved prickles of Solanum junctum are similar to species in the Micracantha clade, but Solanum junctum differs in its branched inflorescences and upright green fruits. These characteristics are shared with other members the Torva clade; within this section Solanum junctum is morphologically most similar to Solanum subinerme and Solanum poinsettiifolium. Solanum subinerme has larger flowers, longer cauline prickles, and often has long straight prickles on the adaxial leaf surface that are lacking in Solanum junctum. Solanum poinsettiifolium has fewer spines, dense white tomentum on the abaxial leaf surfaces, stout unbranched inflorescences, and more extensive interpetalar corolla tissue than Solanum junctum.