Hotspots Of Endemism Research Articles

From emergence to endemicity of highly pathogenic H5 avian influenza viruses in Taiwan

A/goose/Guangdong/1/96-like (GsGd) highly pathogenic avian influenza (HPAI) H5 viruses cause severe outbreaks in poultry when introduced. Since emergence in 1996, control measures in most countries have suppressed local GsGd transmission following introductions, making persistent transmission in domestic birds rare. However, geographical expansion of clade 2.3.4.4 sublineages has raised concern about establishment of endemic circulation, while mechanistic drivers leading to endemicity remain unknown. We reconstructed the evolutionary history of GsGd sublineage, clade 2.3.4.4c, in Taiwan using a time-heterogeneous rate phylogeographic model. During Taiwan’s initial epidemic wave (January 2015 - August 2016), we inferred that localised outbreaks had multiple origins from rapid spread between counties/cities nationwide. Subsequently, outbreaks predominantly originated from a single county, Yunlin, where persistent transmission harbours the trunk viruses of the sublineage. Endemic hotspots determined by phylogeographic reconstruction largely predicted the locations of re-emerging outbreaks in Yunlin. The transition to endemicity involved a shift to chicken-dominant circulation, following the initial bidirectional spread between chicken and domestic waterfowl. Our results suggest that following their emergence in Taiwan, source-sink dynamics from a single county have maintained GsGd endemicity up until 2023, pointing to where control efforts should be targeted to eliminate the disease.

Update on the geographical distribution of freshwater crabs of the Pseudothelphusidae family in the semi-arid region of northeastern Brazil

The humid forest zones of northeastern Brazil are recognized as endemic hotspots for pseudothelphusid crabs. In this study, we report new occurrence records of the pseudothelphusids, Fredius ibiapaba and Kingsleya attenboroughi, in humid soil and streams within humid forests of the semi-arid region of northeastern Brazil. These new records expand the geographical distribution of these crabs, highlighting their potential to inhabit humid forests throughout this region. Furthermore, this information indicates that these crabs, especially K. attenboroughi, are not confined to slopes and patches of humid forests in highland swamps but can also extend to springs in other areas of the Brazilian semi-arid region.

Genetic diversity and prevalence of emerging Rickettsiales in Yunnan Province: a large-scale study

BackgroundRickettsia and related diseases have been identified as significant global public health threats. This study involved comprehensive field and systematic investigations of various rickettsial organisms in Yunnan Province.MethodsBetween May 18, 2011 and November 23, 2020, field investigations were conducted across 42 counties in Yunnan Province, China, encompassing small mammals, livestock, and ticks. Preliminary screenings for Rickettsiales involved amplifying the 16S rRNA genes, along with additional genus- or species-specific genes, which were subsequently confirmed through sequencing results. Sequence comparisons were carried out using the Basic Local Alignment Search Tool (BLAST). Phylogenetic relationships were analyzed using the default parameters in the Molecular Evolutionary Genetics Analysis (MEGA) program. The chi-squared test was used to assess the diversities and component ratios of rickettsial agents across various parameters.ResultsA total of 7964 samples were collected from small mammals, livestock, and ticks through Yunnan Province and submitted for screening for rickettsial organisms. Sixteen rickettsial species from the genera Rickettsia, Anaplasma, Ehrlichia, Neoehrlichia, and Wolbachia were detected, with an overall prevalence of 14.72%. Among these, 11 species were identified as pathogens or potential pathogens to humans and livestock. Specifically, 10 rickettsial organisms were widely found in 42.11% (24 out of 57) of small mammal species. High prevalence was observed in Dremomys samples at 5.60%, in samples from regions with latitudes above 4000 m or alpine meadows, and in those obtained from Yuanmou County. Anaplasma phagocytophilum and Candidatus Neoehrlichia mikurensis were broadly infecting multiple genera of animal hosts. In contrast, the small mammal genera Neodon, Dremomys, Ochotona, Anourosorex, and Mus were carrying individually specific rickettsial agents, indicating host tropism. There were 13 rickettsial species detected in 57.14% (8 out of 14) of tick species, with the highest prevalence (37.07%) observed in the genus Rhipicephalus. Eight rickettsial species were identified in 2375 livestock samples. Notably, six new Rickettsiales variants/strains were discovered, and Candidatus Rickettsia longicornii was unambiguously identified.ConclusionsThis large-scale survey provided further insight into the high genetic diversity and overall prevalence of emerging Rickettsiales within endemic hotspots in Yunnan Province. The potential threats posed by these emerging tick-borne Rickettsiales to public health warrant attention, underscoring the need for effective strategies to guide the prevention and control of emerging zoonotic diseases in China.Graphical

The future of plant diversity within a Mediterranean endemism centre: Modelling the synergistic effects of climate and land-use change in Peloponnese, Greece

Climate- and land-use change stand as primary threats to terrestrial biodiversity. Yet, their synergistic impacts on species distributions remain poorly understood. To address this knowledge gap, we conducted the first-ever comprehensive species distribution analysis on an entire regional endemism centre within an eastern Mediterranean country, incorporating dynamic land-use/land-cover change data together with climate change scenarios. Specifically, we apply species distribution modelling and spatial data analysis techniques to compare the individual and synergistic effects of these environmental drivers on the endemic vascular flora of Peloponnese, focusing on potential range contractions, altitudinal shifts, and habitat fragmentation levels. Moreover, we identify fine-scale present and potential future endemism hotspots within our study area, incorporating taxonomic and phylogenetic information. Overall, we aim to enhance our current understanding of endemism patterns and contribute to the development of future-proof conservation strategies for safeguarding Greece's endangered endemic flora. The integration of land-use change projections with climate change yielded less severe impacts compared to the effects anticipated when considering climatic variables alone. Most taxa are expected to undergo significant range declines and nearly half might experience increased habitat fragmentation, due to the synergistic effects of climate- and land-use change. We identified endemism hotspots, which are concentrated in or along the main Peloponnesian mountain massifs. However, our predictions indicate that areas presently recognized as endemism hotspots will undergo a concerning area decline, across all future scenarios considered in this study. Our findings highlight the importance of including dynamic land-use variables alongside climatic predictors when projecting species distributions under global change. Moreover, we showed that endemism hotspots are not static and considering their potential geographic shifts is paramount to delineate effective forward-looking conservation strategies.

Global hotspots of endemicity, rarity and speciation of aquatic macrophytes

Global hotspots of endemicity, rarity and speciation of aquatic macrophytes

Environmental variation predicts patterns of genomic variation in an African tropical forest frog

Central African rainforests are predicted to be disproportionately affected by future climate change. How species will cope with these changes is unclear, but rapid environmental changes will likely impose strong selection pressures. Here we examined environmental drivers of genomic variation in the central African puddle frog (Phrynobatrachus auritus) to identify areas of elevated environmentally-associated turnover. We also compared current and future climate models to pinpoint areas of high genomic vulnerability where allele frequencies will have to shift the most in order to keep pace with future climate change. Neither physical landscape barriers nor the effects of past Pleistocene refugia influenced genomic differentiation. Alternatively, geographic distance and seasonal aspects of precipitation are the most important drivers of SNP allele frequency variation. Patterns of genomic differentiation coincided with key ecological gradients across the forest-savanna ecotone, montane areas, and a coastal to interior rainfall gradient. Areas of greatest vulnerability were found in the lower Sanaga basin, the southeastern region of Cameroon, and southwest Gabon. In contrast with past conservation efforts that have focused on hotspots of species richness or endemism, our findings highlight the importance of maintaining environmentally heterogeneous landscapes to preserve genomic variation and ongoing evolutionary processes in the face of climate change.

Investigating Endemic Species Conservation Hotspots Based on Species Distribution Models in Swat Region, Hindu Kush Pakistan

For the effective conservation of plant species, it is imperative to manage habitat loss and fragmentation by establishing a protected area network that comprehensively encompasses their habitat. In this study, we identified the suitable habitats for some endemic plant species in the Swat District, Pakistan, to conduct a thorough analysis of proposed protected areas (hotspot areas). Utilizing data from a recent botanical survey, environmental parameters from World-Clim, and various other sources, we determined the habitat of each species using the MaxEnt species distribution model. The modeled habitat suitability for each species were combined to generate maps illustrating endemic richness (hotspots), as well as to prioritize areas based on conservation value and habitat suitability. Future climate projections spanning from 2000 to 2050 were acquired from the WorldClim database Nineteen bioclimatic variables were assessed, incorporating data from three global climate models: CCSM4, HadGEM2-AO, and MPI-ESM-LR. We modeled seven endemic species from the Swat District and, by combining their maps, found three hotspot areas which show more environmental suitability under future climatic conditions. The future model forecasts a significant decrease in population density by the year 2050. Currently, these species exhibit their highest density along the eastern and southern borders of the valley, particularly in the Karakar, Elum border, Mankial Kalam, and Gabral Kalam areas. The anticipated alterations in density and distribution could have a considerable impact not only on the tree species but also on the associated sub flora.

Discovery of an endemism hotspot of freshwater mussels (Bivalvia: Unionidae) in Assam, with a description of two new genera

Abstract The Indian subcontinent houses a unique fauna of freshwater mussels. Tectonic and biogeographic reconstructions indicate that this fauna represents a derivative of Mesozoic Gondwanan biota and that it arrived in Asia on the Indian Plate, using this tectonic block as a ‘biotic ferry’. Though a preliminary integrative revision of the Indian Unionidae was published recently, the level of endemism and taxonomic richness of regional assemblages are unsatisfactorily known. Here, we revise the taxonomy of freshwater mussels from the Brahmaputra River basin based on a large DNA-sequence and morphological dataset that was sampled in Assam, north-eastern India. We managed to collect and sequence topotypes for nearly all nominal species described from the region, except for Lamellidens friersoni and Parreysia smaragdites. Our phylogenetic and morphology-based research reveals that the regional Unionidae assemblage contains nine species, belonging to a single subfamily, the Parreysiinae. Seven species and three genera (Balwantia, Pseudoscabies Bolotov, Sonowal, Kardong, Pasupuleti and Subba Rao gen. nov., and Assamnaia Bolotov, Sonowal, Kardong, Pasupuleti and Subba Rao gen. nov.) appear to be endemic to the region, indicating that the Brahmaputra River may represent an endemism hotspot of global significance. Our findings highlight that this region should be considered a high-priority area for freshwater conservation management.

Hidden hotspots of amphibian biodiversity in China

Identifying and protecting hotspots of endemism and species richness is crucial for mitigating the global biodiversity crisis. However, our understanding of spatial diversity patterns is far from complete, which severely limits our ability to conserve biodiversity hotspots. Here, we report a comprehensive analysis of amphibian species diversity in China, one of the most species-rich countries on Earth. Our study combines 20 y of field surveys with new molecular analyses of 521 described species and also identifies 100 potential cryptic species. We identify 10 hotspots of amphibian diversity in China, each with exceptional species richness and endemism and with exceptional phylogenetic diversity and phylogenetic endemism (based on a new time-calibrated, species-level phylogeny for Chinese amphibians). These 10 hotspots encompass 59.6% of China's described amphibian species, 49.0% of cryptic species, and 55.6% of species endemic to China. Only four of these 10 hotspots correspond to previously recognized biodiversity hotspots. The six new hotspots include the Nanling Mountains and other mountain ranges in South China. Among the 186 species in the six new hotspots, only 9.7% are well covered by protected areas and most (88.2%) are exposed to high human impacts. Five of the six new hotspots are under very high human pressure and are in urgent need of protection. We also find that patterns of richness in cryptic species are significantly related to those in described species but are not identical.

New data and taxonomic changes influence our understanding of biogeographic patterns: A case study in Australian skinks

AbstractSpecies are the most commonly used unit of biogeography research, and in many conservation schemes. For many faunal groups, taxonomy is in a constant state of flux, with new species being described, and our concept of existing species regularly being refined. Using the most diverse lineage of Australian lizards (460+ species), the skinks (Family Scincidae), we quantified the impacts of taxonomic changes over time on our understanding of species richness, endemism and beta diversity. We generated surfaces of species richness, endemism and beta diversity from four editions (1975, 1988, 2000, 2014) of an authoritative field guide to understand how taxonomic shifts, and enhanced biogeographic knowledge, influenced the inferred biogeographic patterns in Australian skinks. The number of recognized Australian skink species has increased 2.3‐fold since 1975. The Wet Tropics was the major hotspot for (mostly locally endemic) species additions. Hotspots of species richness and beta diversity remained broadly similar over time, but some important local hotspots shifted. Endemism hotspots were weakly associated with hotspots of species additions over time except in the Wet Tropics. The major shifts in biogeographic patterns, which were not associated with taxonomic changes, resulted from better knowledge of species distributions through time. We hypothesize that the effects of taxonomy on biogeographic patterns we found generalize across clades and regions—especially away from major research hotspots. We suggest an understanding of the impact of taxonomic changes on conservation priorities for particular regions and taxonomic groups is needed.

Dissimilarity among Species and Higher Taxa of Amphibians in a Hotspot of Biodiversity and Endemism in the Neotropics

The Mexican Republic ranks fifth in the world in terms of amphibian diversity, and within Mexico, the state of Oaxaca has the greatest amphibian richness and endemism. Unfortunately, various factors, such as land use change and global warming, have caused a global crisis that threatens the conservation of this class. In the face of these threats, an analysis of beta diversity provides information that can be applied to conservation strategies, since its study reveals the spatial scaling of diversity loss and clarifies the mechanisms of regional diversity maintenance. In this work, we analyzed the beta diversity at the species and higher taxa level (order, family, subfamily, genus and species) for the amphibians of Oaxaca and their replacement components and the differences in richness for anurans and caudates separately between physiographic subprovinces. Very high beta diversity was recorded, with higher diversity occurring among caudates (0.92) than among anurans (0.84). Species replacement was the component that most contributed to this result, and the subprovinces with substantial environmental differences had the most dissimilar amphibian communities. The results of this study show the need to implement conservation strategies in subprovinces with high amphibian richness and endemism levels, following the example of Sierra Madre de Oaxaca (SMO), where local communities have developed conservation actions in most of the territory.

Global malaria predictors at a localized scale

Malaria is a life-threatening disease caused by Plasmodium parasites transmitted by Anopheles mosquitoes. In 2022, more than 249 million cases of malaria were reported worldwide, with an estimated 608,000 deaths. While malaria incidence has decreased globally in recent decades, some public health gains have plateaued, and many endemic hotspots still face high transmission rates. Understanding local drivers of malaria transmission is crucial but challenging due to the complex interactions between climate, entomological and human variables, and land use. This study focuses on highly climatically suitable and endemic areas in Côte d’Ivoire to assess the explanatory power of coarse climatic predictors of malaria transmission at a fine scale. Using data from 40 villages participating in a randomized controlled trial of a household malaria intervention, the study examines the effects of climate variation over time on malaria transmission. Through panel regressions and statistical modeling, the study investigates which variable (temperature, precipitation, or entomological inoculation rate) and its form (linear or unimodal) best explains seasonal malaria transmission and the factors predicting spatial variation in transmission. The results highlight the importance of temperature and rainfall, with quadratic temperature and all precipitation models performing well, but the causal influence of each driver remains unclear due to their strong correlation. Further, an independent, mechanistic temperature-dependent R0 model based on laboratory data, which predicts that malaria transmission peaks at 25°C and declines at lower and higher temperatures, aligns well with observed malaria incidence rates, emphasizing the significance and predictability of temperature suitability across scales. By contrast, entomological variables, such as entomological inoculation rate, were not strong predictors of human incidence in this context. Finally, the study explores the predictors of spatial variation in malaria, considering land use, intervention, and entomological variables. The findings contribute to a better understanding of malaria transmission dynamics at local scales, aiding in the development of effective control strategies in endemic regions.

The environmental conditions of endemism hotspots shape the functional traits of mammalian assemblages.

Endemic (small-ranged) species are distributed non-randomly across the globe. Regions of high topography and stable climates have higher endemism than flat, climatically unstable regions. However, it is unclear how these environmental conditions interact with and filter mammalian traits. Here, we characterize the functional traits of highly endemic mammalian assemblages in multiple ways, testing the hypothesis that these assemblages are trait-filtered (less functionally diverse) and dominated by species with traits associated with small range sizes. Compiling trait data for more than 5000 mammal species, we calculated assemblage means and multidimensional functional metrics to evaluate the distribution of traits across each assemblage. We then related these metrics to the endemism of global World Wildlife Fund ecoregions using linear models and phylogenetic fourth-corner regression. Highly endemic mammalian assemblages had small average body masses, low fecundity, short lifespans and specialized habitats. These traits relate to the stable climate and rough topography of endemism hotspots and to mammals' ability to expand their ranges, suggesting that the environmental conditions of endemism hotspots allowed their survival. Furthermore, species living in endemism hotspots clustered near the edges of their communities' functional spaces, indicating that abiotic trait filtering and biotic interactions act in tandem to shape these communities.

Revised checklist of endemic vascular plants of Kazakhstan.

We compiled a checklist of endemic vascular plants occurring in Kazakhstan, employing an exhaustive examination of literature sources, herbarium collections, databases and field observations. Our study reveals that 451 taxa can be considered endemic to Kazakhstan, constituting 7.97% of the total vascular plant diversity in the country. These endemic taxa, originating from 139 genera and 34 families, predominantly thrive in the southern regions of Kazakhstan, specifically in the mountain ridges of the Kazakh part of the Tian Shan, including Karatau (123 taxa), Dzungarian Alatau (80 taxa) and Trans-Ili and Kungey Alatau (50 taxa). Notably, 107 endemic species are granted legal protection. Detailed information regarding life form, life cycle, conservation status and geographical distribution across floristic regions was meticulously compiled for each endemic taxon. Of the six groups of life forms, herbs include the highest part of endemic taxa (367 taxa), followed by dwarf semishrubs (25 taxa), shrubs (23 taxa), subshrubs (20 taxa), undershrubs (13 taxa) and trees (3 taxa). The observed life cycles are perennials (408 taxa), annuals (33 taxa) and biennials (10 taxa). This paper serves as a fundamental groundwork for prospective investigations aimed at assessing population sizes and hotspots of plant endemism throughout Kazakhstan, crucial for determining conservation status of endemic plants.

Fine‐scale bee species distribution models: Hotspots of richness and endemism in South Africa with species‐area comparisons

Abstract While global patterns of bee diversity have been modelled, our understanding of fine‐scale regional patterns is more limited, particularly for under‐sampled regions such as Africa. South Africa is among the exceptions on the African continent; its bee fauna (ca. 1253 species) has been well collected and documented, including mass digitising of its natural history collections. It is a region with high floral diversity, high habitat heterogeneity and variable rainfall seasonality. Here, we combine a South African bee species distributional database (877 bee species) with a geospatial modelling approach to determine fine‐scale (~11 × 11 km grid cell resolution) hotspots of bee species richness, endemism and range‐restricted species. Our analyses, based on the probabilities of occurrence surfaces for each species across 108,803 two‐minute grid cells, reveal three bee hotspots of richness: Winter rainfall, Aseasonal rainfall and Early‐to‐late summer rainfall. These hotspots contain large numbers of endemic and geographically restricted taxa. Hotspots with particularly high bee diversity include the Fynbos, Succulent Karoo and Desert biomes; the latter showing 6–20 times more species per unit area than other biomes. Our results conform with global species‐area patterns: areas of higher‐than‐expected bee density are largely concentrated in Mediterranean and arid habitats. This study further enhances our knowledge in identifying regional and global hotspots of richness and endemism for a keystone group of insects and enabling these to be accounted for when setting conservation priorities.

The desert wolf-spider genus Xenoctenus: two endemic species from the Brazilian Caatinga, and a redescription of the type-species, X. unguiculatus (Araneae: Xenoctenidae).

The Caatinga is a nucleus of seasonally dry tropical forest (SDTF) known as a hotspot of diversification and endemism. Despite its importance, this biome is still insufficiently sampled, resulting in extensive knowledge gaps regarding its species richness and composition. In this study we report two species of Xenoctenidae that are endemic to, and widely distributed in the Caatinga. We redescribe and illustrate Odo vittatus (Mello-Leito, 1936), the only xenoctenid species previously known from the Caatinga. We transfer this species to Xenoctenus Mello-Leito,1938, a genus currently known from six species restricted to Argentina, Bolivia, and Colombia. We also newly describe the male of Xenoctenus vittatus comb. nov. and provide new records of this species, which was hitherto known only from the type-locality, throughout the Caatinga and nearby semiarid vegetation formations. We also describe and illustrate a new species, Xenoctenus kaatinga sp. nov., based on males and female specimens collected throughout the Caatinga. Additionally, we propose diagnostic characters for Xenoctenus and redescribe the type-species, X. unguiculatus.

Survey of Melanoplus gaspesiensis and other alpine Acrididae (Orthoptera) on four summits of Gaspésie National Park, Québec, Canada

Abstract Alpine tundra areas are threatened by anthropogenic climate change. They are also often represented as hotspots of endemism. Studying the insect communities associated with these habitats is therefore highly relevant. Melanoplus gaspesiensis Vickery is a grasshopper species known for its extremely limited distribution; it is considered endemic to Mont Albert, on the Gaspé Peninsula, Québec, Canada. Given its extremely limited distribution and with its habitat being particularly sensitive to climate change, the species is likely to soon be considered “at risk” at both the provincial and national levels. In order to confirm the current distribution of M. gaspesiensis, we sampled Acrididae on four alpine summits of the Gaspé Peninsula. Four species of Acrididae were captured. Almost 85% of the captured specimens were M. gaspesiensis, all of which were captured on Mont Albert. Our data are thus coherent with the species being endemic to that summit. The unique geology of Mont Albert (serpentine) may explain why M. gaspesiensis appears to be restricted to this one summit.

Historic deforestation and non‐native plant invasions determine vegetation trajectories across an oceanic archipelago

AbstractQuestionsOceanic islands are global hotspots of endemism and evolutionary radiations but many have been severely degraded by human activities and biological invasions. We evaluated the pace and direction of the natural recovery of ecosystems over 77 years across a subtropical oceanic archipelago including islands of various size, elevation, histories of human settlement and deforestation, and invasions by non‐native plants and mammals. This information is essential to guide the ecological restoration of the archipelago.LocationForest vegetation on nine of the Ogasawara Islands in the northwestern Pacific Ocean.MethodsWe first digitized historical vegetation data of the Ogasawara Islands collected during field surveys in 1935. Then, after checking their species compositions, we integrated past and present plant community types. Finally, we identified the landscape‐scale changes in forest vegetation by comparing vegetation maps from 1935, 1979 and 2012.ResultsOver 77 years, the vegetation trajectories of each island varied depending on the introduction of invasive alien species and the remaining proportion of native forest, the latter of which had a strong influence on the recoverability of native forest.ConclusionsOur results highlight the importance of the history of invasive species introductions and the remaining proportion of native forest—both of which reflect the intensity of anthropogenic disturbance—in determining the degree of human intervention needed for restoration on oceanic islands.

The climate crisis affects Mediterranean marine molluscs of conservation concern

AbstractAimThe Mediterranean Sea is a hotspot of endemism and it is warming at two to three times the rate of the global ocean. The continental masses that surround it constrain species range shifts. Therefore, as seawater temperature increases, distributions of marine species may contract into few small cooler refugia, with consequent risk of extinction from range contraction and fragmentation, particularly for endemics. We assess this risk for 15 molluscs of conservation concern occurring in the Mediterranean Sea. Invertebrates have been rarely assessed so far, despite their diversity and their importance for ecosystem functioning.LocationThe Mediterranean Sea and Eastern Atlantic Ocean.MethodsWe used ensemble species distribution models to project the future range of our target species and assess their IUCN Red List status.ResultsAs hypothesized, our models predicted major range shifts, contractions and fragmentation in the Mediterranean Sea for all species. Under moderate emission scenarios such as RCP4.5, up to 12 of the 15 target species will be eradicated from the eastern and southern warmer sectors. Under severe emission scenarios such as RCP8.5 and by the end of the century, we predict the global extinction of the endemic Patella ferruginea and Pinna nobilis. Non‐endemic species may buffer range loss in the Mediterranean with range gains in the Atlantic Ocean. Still, we predict that only a single species, Zonaria pyrum, will have marginal total range gains in future climate warming scenarios.Main conclusionsEight species will become threatened and the fate of Patella ferruginea and Pinna nobilis contrasts the belief that marine species are less prone to extinction than continental species under a warming climate.

Microlicia crenatifolia (Melastomatacae), a new species from the westernmost limits of the Diamantina Plateau, Minas Gerais, Brazil

Microlicia crenatifolia is described from the Diamantina Plateau, a well-known hotspot of plant endemism in southeastern Brazil. It can be recognized by its small leaves (up to 8.3 mm long) that are conspicuously crenulate to slightly serrate, short floral pedicels (0.7–1.0 mm long), and linear calyx lobes that are externally glandular-punctate and covered with short gland-tipped trichomes 0.1–0.3 mm long. We provide line drawings, SEM photos of leaves, seeds and indumentum, a distribution map, and an identification key to M. crenatifolia and putative relatives (M. canastrensis, M. pabstii, M. serratifolia, and M. thomazii).