Find research datasets worth reusing

opencc-by-3.0Oct 2016View details →

Fig. 14 in New narrow-range endemic land snails from the sky islands of northern South Africa (Gastropoda: Streptaxidae and Urocyclidae)

Fig. 14. Sheldonia wolkbergensis sp. nov., holotype, shell diameter 7.7 mm (NMSA P0156/T4074).

opencc-by-3.0Oct 2014View details →

Fig. 33 in A mountain of millipedes I: An endemic species-group of the genus Chaleponcus Attems, 1914, from the Udzungwa Mountains, Tanzania (Diplopoda, Spirostreptida, Odontopygidae)

Fig. 33. The number of studied specimens (males) per species.

opencc-zeroJun 2020View details →

Data from: Habitat loss in the restricted range of the endemic Ghanaian cichlid Limbochromis robertsi

Remote sensing has become an integral and invaluable tool to inform biodiversity conservation and monitoring of habitat degradation and restoration over time. Despite the disproportionately high levels of biodiversity loss in freshwater ecosystems worldwide, ichthyofauna are commonly overlooked in favor of other keystone species. Freshwater fish, as indicators of overall aquatic ecosystem health can also be indicators of larger scale problems within an ecosystem. As a case study with multi-temporal, multi-resolution satellite imagery, we examined deforestation and forest fragmentation around the Atewa Forest Reserve, Ghana. Within small creeks, Limbochromis robertsi, a unique freshwater cichlid with an extremely limited distribution range can be found. Historically, the land cover in the area has undergone substantial deforestation for agriculture and artisanal small-scale mining. In the 1389 km2 study area we found deforestation accelerated along with increased forest fragmentation in the 2014 – 2017 period (167.4 km2 of deforestation) with the majority of the forest loss along the river and creek banks due to small-scale mining operations and increased agriculture. Field visits indicated a decrease in the total L. robertsi population by approximately 90% from the early 1990s to 2018. Its distribution has been reduced to higher elevations by anthropogenic habitat barriers at low elevations and the presence of predatory species. Loss of Riparian forest through land use and cover change to mining and agriculture contributes to the habitat degradation for these endemic species. The fine spatial and temporal scale studies required to assess habitat characteristics is not captured by global or continental scale datasets.

opencc-zeroMay 2020View details →

Data from: Pollen limitation in the endangered Chinese endemic species Sinocalycanthus chinensis

Pollen limitation negatively impacts endangered and endemic plants with small fragmented populations, such as Sinocalycanthus chinensis, an endangered plant endemic to China. In this study, we analyzed the pollen limitation of the S. chinensis Damingshan (DMS) population in 2006, 2009, and 2010, and crossed plants with mates separated by different distances, both within and between populations. The DMS population exhibited strong pollen limitation in fruit set, seed set, and seeds per fruit in 2006, 2009, and 2010. The average accumulated pollen limitation (for fruit set times seeds per fruit) was 0.510 ± 0.180. Progeny crossed with pollen from intermediate neighboring plants within the same population (separated by 30 – 50 m from pollen recipients) had the lowest fitness. No optimal outcrossing distance was found within the DMS population. Progeny from crosses with the SXW and DLS populations performed relatively better, while those from crosses with QLF and LXS populations performed worse. Compared with average reproductive success, outbreeding depression was found in progeny from crosses with the LXS and QLF populations. Reproductive success from pure self-pollination indicated S. chinensis is self-compatible. Geitonogamous selfing increased reproductive success. Based on geitonogamous selfing, the proportion of selfed offspring was relatively high. These results provide basic references for the conservation of this species.

opencc-zeroJul 2020View details →

Data from: Multiple glacial refugia and contemporary dispersal shape the genetic structure of an endemic amphibian from the Pyrenees

Historical factors (colonization scenarios, demographic oscillations) and contemporary processes (population connectivity, current population size) largely contribute to shaping species' present-day genetic diversity and structure. In this study, we use a combination of mitochondrial and nuclear DNA markers to understand the role of Quaternary climatic oscillations and present-day gene flow dynamics in determining the genetic diversity and structure of the newt Calotriton asper (Al. Dugès, 1852), endemic to the Pyrenees. Mitochondrial DNA did not show a clear phylogeographic pattern and presented low levels of variation. In contrast, microsatellites revealed five major genetic lineages with admixture patterns at their boundaries. Approximate Bayesian computation analyses and linear models indicated that the five lineages likely underwent separate evolutionary histories and can be tracked back to distinct glacial refugia. Lineage differentiation started around the Last Glacial Maximum at three focal areas (western, central and eastern Pyrenees) and extended through the end of the Last Glacial Period in the central Pyrenees, where it led to the formation of two more lineages. Our data revealed no evidence of recent dispersal between lineages, whereas borders likely represent zones of secondary contact following expansion from multiple refugia. Finally, we did not find genetic evidence of sex-biased dispersal. This work highlights the importance of integrating past evolutionary processes and present-day gene flow and dispersal dynamics, together with multilocus approaches, to gain insights into what shaped the current genetic attributes of amphibians living in montane habitats.

opencc-zeroAug 2020View details →

Data from: Bird diversity and endemism along a land-use gradient in Madagascar: the conservation value of vanilla agroforests

<div> <div> Land-use change is the most important driver of biodiversity loss worldwide and particularly so in the tropics, where natural habitats are transformed into large-scale monocultures or heterogeneous landscape mosaics of largely unknown conservation value. Using birds as an indicator taxon, we evaluated the conservation value of a landscape mosaic in north-eastern Madagascar, a biodiversity hotspot and the center of global vanilla production. We assessed bird species richness and composition by conducting point counts across seven prevalent land-use types (forest- and fallow-derived vanilla agroforests, woody and herbaceous fallow that are part of a shifting cultivation system, rice paddy, forest fragment and contiguous old-growth forest). We find that old-growth forest had the highest species richness, driven by a high share of endemics. Species richness and community composition in forest-derived vanilla agroforest was similar to forest fragment, whereas fallow-derived vanilla agroforest was most comparable to woody fallow. The open land-use types herbaceous fallow and rice paddy had fewest species. Across forest fragment, vanilla agroforests and woody fallow, endemic bird species richness was positively correlated to landscape-scale forest cover. We conclude that both fallow- and forest-derived vanilla agroforests play an important but contrasting role for bird conservation in the landscape: Fallow-derived agroforests are less valuable but take fallow land out of the shifting cultivation cycle, possibly preventing further degradation. Conversely, forest-derived agroforests contribute to forest degradation but may avoid total loss of forest fragments. Considering the land-use history of agroforests may thus be a promising avenue for future research beyond the case of vanilla. </div> </div>

opencc-zeroOct 2020View details →

Under the radar: genetic assessment of Rio Grande Shiner (Notropis jemezanus) and Speckled Chub (Macrhybopsis aestivalis), two Rio Grande basin endemic cyprinids that have experienced recent range contractions

The Rio Grande drainage of the southwestern United States and Mexico has undergone intense anthropogenic alteration by water diversions, extraction and associated habitat changes. These alterations have disproportionately impacted the pelagic broadcast spawning guild of minnows (pelagophils). Several Rio Grande endemic pelagophils, including the co-occurring Rio Grande Shiner (Notropis jemezanus) and Speckled Chub (Macrhybopsis aestivalis), have experienced dramatic recent range-wide declines yet have slipped under the radar of conservation efforts. The status of N. jemezanus and M. aestivalis in the Rio Grande and Pecos River was evaluated and standing genetic variation were characterized. Genetic evidence indicates that populations of both species found in the Rio Grande and Pecos River are genetically distinct. Additionally, 159 outlier loci were identified in M. aestivalis suggesting possible local adaptation in the Rio Grande and Pecos River populations. Though range-wide genetic data are limited, N. jemezanus populations in both rivers harbor considerable genetic diversity. Mitochondrial data from both taxa are consistent with a history of secondary contact between formerly isolated populations with deeply divergent haplotypes found within the Rio Grande and Pecos River populations of N. jemezanus and within the Rio Grande population of M. aestivalis. Extensive survey efforts in the lower Rio Grande and its tributaries in Texas document significant range contraction and near extirpation of N. jemezanus from this part of the basin; highlighting the need for immediate action to protect the species.

opencc-zeroAug 2021View details →

Dominance of endemics in the reef fish assemblages of the Hawaiian Archipelago

Aim: Species ranges provide a valuable foundation for resolving biogeographic regions, evolutionary processes, and extinction risks. To inform conservation priorities, here we develop the first bioregionalization based on reef fish abundance of the Hawaiian Archipelago, which spans nearly 10° of latitude across 2,400 km, including 8 high volcanic islands in the populated main Hawaiian Islands (MHI), and 10 low islands (atolls, shoals, and islets) in the remote northwestern Hawaiian Islands (NWHI).. Location: The Hawaiian Archipelago. Taxon: Fishes (276 taxa). Methods: We compiled 5,316 visual fish surveys at depths of 1-30 m from throughout the Hawaiian Archipelago. Geographic range (km2) for each species was measured as extent of occurrence (EOO) and area of occurrence (AOO). PERMANOVA and PCO were used to investigate drivers of fish assemblage structure. Distance-based multivariate analyses were used to evaluate the relationship between fish assemblage structure and predictor variables including latitude, reef area, temperature, chlorophyll-a, wave-energy, and human population density. Results: Distinct fish assemblages exist in the MHI and NWHI, with two additional faunal breaks driven primarily by endemic species abundance. Latitude explained 37% of the variability in fish assemblages, with reef area accounting for an additional 9%. EOO showed a significant correlation with latitude. Endemics comprised 52-55% of the numerical abundance at the northern end of the archipelago but only 17% on Hawai'i Island in the extreme south. Maximum size and activity regime (day vs. night) explained the most variation in the abundance of endemics. Main conclusions: The Hawaiian fish assemblages are strongly influenced by endemic species, affirming the archipelago as a biodiversity hotspot of high conservation value. The higher abundance of endemics in the NWHI may represent preadaptation to oceanic (oligotrophic) conditions. Resolution of distinct bioregions across the archipelago provides a better understanding of reef fish macroecology, with implications for management at the archipelago scale.

FIG. 5 in Annotated checklist of the endemic Tetrapoda species of Iran

FIG. 5. — Acanthodactylus nilsoni Rastegar-Pouyani, 1998. Photo by H. Faizi.

FIG. 1 in Annotated checklist of the endemic Tetrapoda species of Iran

FIG. 1. — Bufotes luristanicus (Schmidt, 1952). Photo by M. Najibzadeh.

FIG. 10 in Annotated checklist of the endemic Tetrapoda species of Iran

FIG. 10. — Endemicity percentage of Tetrapoda species in Iran.

FIG. 3 in Annotated checklist of the endemic Tetrapoda species of Iran

FIG. 3. — Neurergus kaiseri Schmidt, 1952. Photo by M. Najibzadeh.

FIG. 2 in Annotated checklist of the endemic Tetrapoda species of Iran

FIG. 2. — Rana pseudodalmatina Eiselt & Schmidtler, 1971. Photo by M. Najibzadeh.

FIG. 9 in Annotated checklist of the endemic Tetrapoda species of Iran

FIG. 9. — Scarturus cf. williamsi (Hamidi, Darvish & M. Matin, 2016). Photo by K. Hamidi.

FIG. 11 in Annotated checklist of the endemic Tetrapoda species of Iran

FIG. 11. — Topographic map of Iran (www.worldofmaps.net).

opencc-by-4.0Oct 2020View details →

FIG. 3 in Typification of three Iraqi endemic taxa of Centaurea L. (Asteraceae, Cardueae)

FIG. 3. — Lectotype of Centaurea longipedunculata Sch. Bip. ex Boiss., Kotschy 374 (P02585330).

opencc-by-4.0Oct 2020View details →

FIG. 1 in Typification of three Iraqi endemic taxa of Centaurea L. (Asteraceae, Cardueae)

FIG. 1. — Lectotype (second-step) of Centaurea foveolata Blakelock, Guest 3773 (K000794077).

opencc-by-4.0Oct 2020View details →

FIG. 2 in Typification of three Iraqi endemic taxa of Centaurea L. (Asteraceae, Cardueae)

FIG. 2. — Lectotype (second-step) of Centaurea fusiformis Blakelock, Guest 1589 (K000794106).

opencc-by-4.0Jun 2016View details →

Fig. 1 in Cytogenetic analysis of Baryancistrus xanthellus (Siluriformes: Loricariidae: Ancistrini), an ornamental fish endemic to the Xingu River, Brazil

Fig. 1. Live photograph of Baryancistrus xanthellus, LIA 1629.