Distribution of Panama’s narrow-range trees: are there hot-spots?

Background Tree species with narrow ranges are a conservation concern because heightened extinction risk accompanies their small populations. Assessing risks for these species is challenging, however, especially in tropical flora where their sparse populations seldom appear in traditional plots and inventories. Here, we utilize instead large scale databases that combine tree records from many sources to test whether the narrow-range tree species of Panama are concentrated at certain elevations or in certain provinces. Past investigations have suggested that the Choco region of eastern Panama and the high mountains of western Panama may be potential hotspots of narrow-range tree species. Methods All individual records were collected from public databases, and the range size of each tree species found in Panama was estimated as a polygon enclosing all its locations. Species with ranges <20,000 km2 were defined as narrow endemics. We divided Panama into geographic regions and elevation zones and counted the number of individual records and the species richness in each, separating narrow-range species from all other species. Results The proportion of narrow endemics peaked at elevations above 2000 m, reaching 17.2% of the species recorded. At elevation <1500 m across the country, the proportion was 6-11%, except in the dry Pacific region, where it was 1.5%. Wet forests of the Caribbean coast had 8.4% narrow-range species, slightly higher than other regions. The total number of narrow endemics, however, peaked at mid-elevation, not high elevation, because total species richness was highest at mid-elevation. Conclusions High elevation forests of west Panama had higher proportions of narrow endemic trees than low-elevation regions, supporting their hot-spot status, while dry lowland forests had the lowest proportion. This supports the notion that montane forests of Central America should be a conservation focus. However, given generally higher diversity at low- to mid-elevation, lowlands are also important habitats for narrow-range tree species, though conservation efforts here may not protect narrow-range tree species as efficiently.

THE VIOLETS OF THE BRAZILIAN SAVANNA: A REVISION OF THE POMBALIA LANATA COMPLEX (VIOLACEAE), WITH DESCRIPTIONS OF TWO NEW SPECIES

Pombalia Vand. (Violaceae) is represented in the Cerrado by a well-supported monophyletic group of species known as the Pombalia lanata complex, characterised by some unique vegetative and reproductive features within the genus. This group includes six species – Pombalia cristalina, P. insignis, P. lanata, P. poaya, P. strigoides and P. velutina – the first two of which are new to science. Pombalia lanata shows the widest geographical distribution throughout the Central Brazilian Plateau and the Espinhaço Range in Minas Gerais state, with a disjunction in Misiones Province, Argentina. Because most species in this group are narrow endemics, we evaluated the conservation status of all taxa. An identification key for the species, descriptions, illustrations, maps of geographical distribution and nomenclatural notes are also provided.

A Revised Classification of Glossopetalon (Crossosomataceae) Based on Restriction Site-Associated DNA Sequencing

Glossopetalon inhabits arid regions in the American west and northern Mexico on limestone substrates. The genus comprises four species: G. clokeyi, G. pungens, G. texense, and G. spinescens. Three of the species are narrow endemics. The fourth, G. spinescens, is a widespread species with six recognized varieties. All six varieties are intricately branched shrubs that have been difficult to identify due to a lack of clearly delineating morphological characters. Characters typically used to differentiate the varieties of G. spinescens, such as stem coloration, leaf blade size, and presence of stipules, are highly variable within and among populations. A custom protocol of double digest restrictionsite associated DNA sequencing (ddRAD) was used to resolve the phylogeny of Glossopetalon and address if population genetic data analyses (such as STRUCTURE, SVDquartets, and phylogenetic networks) support the recognition of six varieties of G. spinescens. Glossopetalon was fully supported as monophyletic and G. pungens was resolved sister to the remaining taxa in the genus. The varieties of G. spinescens were resolved as two distinct lineages corresponding to their biogeography, one to the northwest (lineage 1) and one to southeast (lineage 2) of the species range. Glossopetalon clokeyi was resolved at the base of lineage 1 and G. texense was embedded within lineage 2 sister to G. spinescens var. spinescens. Taxonomic changes include the recognition of G. texense and G. clokeyi as varieties of G. spinescens and description of a unique population from northern Arizona as a new variety, G. spinescens var. goodwinii.

A checklist and conservation status of vascular plants in the Limestone forest of Metropolitan Ilocos Norte Watershed Forest Reserve, Northwestern Luzon, Philippines

Batuyong MAR, Calaramo MA, Alejandro GJD. 2020. A checklist and conservation status of vascular plants in the Limestone forest of Metropolitan Ilocos Norte Watershed Forest Reserve, Northwestern Luzon, Philippines. Biodiversitas 21: 3969-3981. The Metropolitan Ilocos Norte Watershed Forest Reserve (MINWFR) is among the remaining intact limestone formations and a critical protected area in Northwestern Luzon. There have been few published floristic studies despite its undeniable rich biological importance. Therefore, this paper primarily aims to provide a preliminary checklist of vascular plants in MINWFR and their conservation status. Consequent field visits and surveys were made from April 2019 to March 2020. Results revealed a total of 173 species distributed in 140 genera belonging to 59 families. The most represented families are Rubiaceae, Fabaceae, Orchidaceae, and Malvaceae. This forest supports 49% or 28.65 % local endemics, five of which are narrow endemics, namely Cyanometra warburgii, Pyrostria triflora, Syzygium ilocanum, Thrixspermum nicolasiorum, and Antirhea microphylla. The latter, however, extends up to Ilocos Sur. Based on IUCN criteria and DENR records, a total of 18 species are threatened, one species is recorded as critically endangered, five endangered, nine vulnerable, three other threatened, two near threatened, 55 as least concern, and the rest are not evaluated. Other noteworthy species present in the area are the two dominant endangered species, Podocarpus costalis, and Podocarpus polystachyus. An interesting spinescent Rubiaceae species were recorded and currently under examination to establish its identity. This checklist serves as a basis to effectively manage this vulnerable area surrounded by human-induced disturbances and threats.

The Demographic History of Micro-endemics: Have Rare Species Always Been Rare?

Extinction has increased as human activities impact ecosystems. Conservation assessments for the IUCN red list are a fundamental tool in aiding the prevention of further extinction, yet, relatively few species have been thoroughly assessed. To increase the efficiency of assessments, novel approaches are needed to highlight threatened species that are currently data deficient. Many Madagascan plant species currently have extremely narrow ranges, but this may not have always been the case. To assess this, we used high-throughput DNA sequencing for 2-5 individuals of each species - reflecting the paucity of samples available for rare species. We estimated effective population size (Ne) for each species and compared this to census population (Nc) sizes when known. In each case, Ne was an order of magnitude larger than Nc – a signature of rapid, recent population decline. We then estimated the demographic history of each species, tracking changes in Ne over time. Five out of ten species displayed significant population declines towards the present (68–90% decreases). Our results for palm trees indicate that it is possible to predict extinction risk, particularly in the most threatened species. We performed simulations to show that our approach has the power to detect population decline during the Anthropocene, but performs less well when less data is used. Similar declines to those in palms were observed in data deficient species or those assessed as of least concern. These analyses reveal that Madagascar’s narrow endemics were not always rare, having experienced rapid decline in their recent history. Our approach offers the opportunity to target species in need of conservation assessment with little prior information, particularly in regions where human modification of the environment has been rapid.SummaryCurrent IUCN conservation assessment methods are reliant on observed declines in species population and range sizes over the last one hundred years, but for the majority of species this information is not available. We used a population genetic approach to reveal historical demographic decline in the rare endemic flora of Madagascar. These results show that it is possible to predict extinction risk from demographic patterns inferred from genetic data and that destructive human influence is likely to have resulted in the very high frequency of narrow endemics present on the island. Our approach will act as an important tool for rapidly assessing the threatened status of poorly known species in need of further study and conservation, particularly for tropical flora and fauna.

Serpentine mountain uplift in northern Japan triggered the divergence of a narrow endemic from a widespread (sub)arctic Asia-Alaska species complex of Lagotis (Plantaginaceae)

In the circumboreal region, plants often have extremely-wide species ranges. Lagotis minor-glauca species complex widespread from (sub)arctic Asia to Alaska, however, have two allied narrow endemics in northern Japan: a serpentine plant L. takedana endemic to the Yubari Mountains (Mt. Yubari) and a non-serpentine plant L. yesoensis endemic to the Taisetsu Mountains (Mt. Taisetsu). Elucidating their origins sheds light on drivers for secondary-speciation of widespread circumboreal plants. To infer phylogenetic distinctiveness of two narrow endemics with those related taxa, which contained 25 out of all the 29 species of the genus, chloroplast DNA (cpDNA), nuclear ribosomal (nrITS), two low copy nuclear gene (LCN) markers and genome-wide single-nucleotide polymorphism genotyping (MIG-seq) were used. In the result of cpDNA analyses, the Lagotis minor-glauca species complex formed a clade. Within the clade, L. yesoensis and a portion of L. glauca samples formed a subclade. However, monophyly of each of the four species was not supported. In the results of nrITS and two LCN analyses, L. takedana was monophyletic, while monophyly was not recovered for each L. yesoensis, L. glauca, and L. minor. Based on a Bayesian dating analysis using nrITS data, the age of the most recent common ancestor of L. takedana was Ma (95% confidence interval: 0.05-1.75 Ma). Possible scenario is that an ancestral linage being adapted to serpentine soils migrated into the alpine habitat of Mt. Yubari, that was formed with mountain uplift by the early Pleistocene, and subsequently reproductively isolated from non-serpentine populations and speciated. The contrasting result of L. yesoensis, that was phylogenetically indistinct, is possibly explained by incorrect taxonomy, or alternatively, shallow history and incomplete lineage sorting. In Mt. Taisetsu, massive volcanic eruptions had occurred the Early Pleistocene and even after the last glacial period, suggesting that alpine plants have not migrated into and established populations in Mt. Taisetsu until very recently. To fully resolve the phylogeny of the three species L. yesoensis, L. glauca, and L. minor, further analyses using high resolution molecular markers are needed. The present study illustrated that two narrow endemics in northern Japan diverged from the widespread species include phylogenetically distinctive and indistinctive species, owing to historical orogeny and ecological factors.

Phylogeny and biogeography of the African Bathyergidae: a review of patterns and processes

Background We review genealogical relationships, biogeographic patterns and broad historical drivers of speciation within the Bathyergidae, a group of endemic African rodents, as well as identify key taxa which need further research. Methods We sourced comparable cytochrome b sequence data (comparable data available for all members for the Family) and geographic information for all six genera of the African subterranean rodent. This information was combined into the most comprehensive and geographically representative evolutionary study for the Bathyergidae to date. Results Species richness within the Bathyergidae appears to be underestimated, with undescribed taxa in five of the six genera. Biogeographic patterns suggest large historical distributions, which were repeatedly fragmented by major landscape changes (especially rifting, uplift and drainage evolution) since the Miocene. Aside from vicariant events, other factors (ecological specialization, population-level responses and climatic change) may have been instrumental in driving divergences in the Bathyergidae. As such, adaptive differences may exist among both populations and species across their discrete ranges, driving independent evolutionary trajectories among taxa. In addition, highly fragmented distributions of divergent (and often relict) lineages indicates the possibility of narrow endemics restricted to diminishing suitable habitats. From this, it is clear that a systematic revision of the Bathyergidae is necessary; such a revision should include comprehensive sampling of all putative taxa, the addition of genomic information to assess adaptive differences, as well as ecological information.

Discovery of a new species of the genus Stygepactophanes from a groundwater-fed spring in southern France (Crustacea, Copepoda, Harpacticoida, Canthocamptidae)

A new species of the genusStygepactophanesMoeschler &amp; Rouch, 1984 (Copepoda, Harpacticoida, Canthocamptidae) is established to accommodate a small canthocamptid population collected from a spring system in the “Parc du Mercantour”, Var catchment, southern France. The population analysed in the present study is defined by a set of morphological characters of the female, namely a very large maxilliped, a rudimentary mandibular palp, P1 with 3-segmented exopod and 2-segmented endopod, a falcate terminal claw of the P1 endopod, dorsal seta of caudal rami inserted on the inner margin, and anal operculum not overreaching the insertion of the caudal rami, thus supporting its assignment into the genusStygepactophanes. The new speciesStygepactophanesoccitanusshows marked differences with the nominotypical species of the genus that was originally described by monotypy with the speciesStygepactophanesjurassicusMoeschler &amp; Rouch, 1984. The main diagnostic traits ofS.jurassicusare the absence of the P5 and a falcate outer terminal claw of P1 endopod.Stygepactophanesjurassicusalso shows a reduced armature of the antennal exopod, bearing one seta, 1-segmented P2–P4 endopods, a reduced armature of P2–P4 exopodal segments 3 (3,4,4 armature elements, respectively), P6 bearing only one long seta, a rounded short and smooth anal operculum. Conversely the female ofS.occitanusGalassi &amp; Fiers,sp. n.has a well-developed P5, with rudimentary intercoxal sclerite, together with a falcate outer terminal claw of P1 endopod, antennal exopod bearing two elements, P4 endopod 1-segmented versus 2-segmented in P2–P3, P2–P4 exopodal segment 3 with five armature elements, P6 with three setae of different lengths, rounded anal operculum, bearing 3–4 strong spinules.According to our present knowledge,S.occitanusGalassi &amp; Fiers,sp. n.is assigned to the genusStygepactophanesas the most conservative solution, waiting for the male to be discovered. The genusStygepactophanesrepresents a distinct lineage within the harpacticoid family Canthocamptidae that colonised southern European groundwater, the genus being known only from the saturated karst in Switzerland and a fissured saturated aquifer in southern France. Both species of the genus are stygobites and narrow endemics, the nominotypical species being known from the type locality Source de la Doux in Délemont (Switzerland), andS.occitanusGalassi &amp; Fiers,sp. n.described herein from a spring system of the Var catchment (France).

Prioritizing Conservation of Medicinal Flora in the Himalayan Biodiversity Hotspot: An Integrated Ecological and Socioeconomic Approach

SummaryTo achieve the challenging goals of minimizing loss of species and achieving sustainable use of biodiversity, conservation prioritization merits urgent research attention. The present study identifies the priority of conservation for the medicinal flora of the Jammu and Kashmir (J&K) region, a Himalayan biodiversity hotspot. A total of 881 medicinal plant species were scored based on key ecological (endemism, threat status) and socioeconomic (use value, mode of harvesting) criteria, and 50 of these are prioritized for conservation; most of these are narrow endemics. Worryingly, all of the 50 prioritized species are currently recognized under different International Union for Conservation of Nature and Natural Resources threat categories, are highly prized for their use in traditional medicine in the region and are precious sustainable bioresources for the herbal industry. Most of these prioritized species are being harvested illegally. This integrated ecological and socioeconomic study has immediate implications for evidence-based and target-orientated conservation policy and practice in this Himalayan region.

Taxonomic revision of the neotropical genus Homalolepis Turcz. (Simaroubaceae)

Homalolepis Turcz. is a neotropical, monophyletic genus, recently reestablished as a segregate from Simaba Aubl., based on molecular and morphological grounds. As here defined, Homalolepis comprises 28 species, mainly distributed in tropical South America, with one species extending to Central America. Most species occur within the Cerrado and Atlantic forest domains in Brazil and only a few species occur in the Caatinga and Amazonian domains or in other countries. Most of the species are narrow endemics, and two (H. suaveolens and H. maiana) are presumably extinct. The present revision treatment is primarily based on the examination of about 1300 specimens from 58 herbaria. Natural populations of 20 species were also studied. Extensive field work improved the representativeness of collections of several species which were poorly known until now, and it was critical for achieving accurate species circumscriptions, especially for some species complexes present in the genus. Twenty-three species were transferred from Simaba to Homalolepis, seven names lectotypified, an epitype designated, seven new species described, and one reestablished. The infrageneric classification is reevaluated, with an updated morphological circumscription of two traditional sections. This revision provides the taxonomic data on nomenclatural types, including synonymies, morphological descriptions, etymology of species names, common names and uses, illustrations and photos, and brief discussions on phenology, taxonomy and nomenclature. Distribution maps are provided for each species, along with biogeographical and ecological comments.