Dennis Rödder

Leibniz Institute for Biodiversity Change Analysis (LIB) - Research Museum Alexander Koenig · Vertebrate Department

Aim The use of ecological niche models (ENMs) to predict potential distributions of species is steadily increasing. A necessary assumption is that climatic niches are conservative, but recent findings of niche shifts during biological invasion indicate that this assumption is not always valid. Selection of predictor variables may be one reason for...

Aim Studies of environmental niche shift/niche conservatism that are based on species distribution modelling require a quantification of niche purity and potential overlap. Although various metrics have been proposed for this task, no comparisons of their performance are available yet that express the linearity of range shifts and error-proneness....

In the Grinnellian niche concept, the realized niche and potential distribution is characterized as an interplay among the fundamental niche, biotic interactions and geographic accessibility. Climate is one of the main drivers for this concept and is essential to predict a taxon’s distribution. Mechanistic approaches can be useful tools, which use...

Aim: Hyper-arid sandy and rocky fields rank among the least biologically diverse habitats of the desert biome, yet knowledge of local biodiversity patterns is also extremely poor. In the Sahara Desert, palaeoclimate oscillations affected the extent of hyper-arid habitats, but it is unclear how these dynamics determined the evolution and distributio...

Habitat change and fragmentation are the primary causes of biodiversity loss worldwide. Recent decades have seen a surge of funding, published papers and citations in the field as these threats to biodiversity continue to rise. However, how research directions and agenda are evolving in this field remains poorly understood. In this study, we examin...

Vietnam belongs to one of the most well-known global biodiversity hotspots. However, its biodiversity is being threatened by multiple factors such as rapid growth of the human population, habitat destruction, overexploitation, and climate change. To better prioritize conservation measures for Vietnam’s mammal fauna, this study attempts to identify...

The angelshark, Squatina squatina, is listed as Critically Endangered on the IUCN Red List of Threatened Species, and remaining populations are highly fragmented throughout its historical distribution. The Canary Islands archipelago in the North East Atlantic has been identified as a uniquely large stronghold for the species. In the present study,...

Chytridiomycosis is one of the greatest threats to the diversity of amphibians worldwide. Caused by the chytrid fungus Batrachochytrium salamandrivorans (Bsal), it plays a decisive role in species declines. Bsal is particularly harmful to the European fire salamander (Salamandra salamandra), causing ulcerations, anorexia and ataxia, which ultimatel...

The angelshark, Squatina squatina , is listed as Critically Endangered on the IUCN Red List of Threatened Species and remaining populations are highly fragmented throughout its historical distribution range. The Canary Islands archipelago in the North East Atlantic has been identified as a uniquely large stronghold for the species. In the present s...

Madagascar, as one of the global biodiversity hotspots, hosts numerous unique terrestrial mammal species that need urgent protection. To identify priority species for conservation, an updated list of terrestrial Malagasy mammal species was compiled, including their threat status, distribution, endemism level, Convention on International Trade in En...

The South American bushmaster Lachesis muta is currently considered a valid taxon with no recognized subspecies. However, its wide distribution with discontinuous populations, the restricted sampling of molecular data in previous studies, and the inherent difficulty in obtaining diagnostic data, preclude a detailed evaluation of the taxonomic statu...

Despite suffering dramatic declines due to habitat loss and overexploitation, tortoises and freshwater turtles in Southeast Asia remain understudied. Sustainable forest management offers a promising approach for advancing the conservation of threatened turtle populations. This study examines the effect of reduced impact logging (RIL), a sustainable...

The Cenozoic topographic development of the Himalaya-Tibet orogen (HTO) substantially affected the paleoenvironment and biodiversity patterns of High Asia. However, concepts on the evolution and paleoenvironmental history of the HTO differ massively in timing, elevational increase and sequence of surface uplift of the different elements of the orog...

Amidst the era of rapid decline in insect diversity, the role of protected areas (PAs) in conserving current insect diversity is more significant than ever. Previous studies indicate that the species‐diverse regions in Iran fall within two global biodiversity hotspots (GBHs): the Irano‐Anatolian hotspot in the north and the Caucasus hotspot in the...

Exploitation of different locomotor substrates in different ecological niches has driven the evolution of specialized morphological structures, and similar ecological demands, such as the structure of the microhabitat, often lead to convergent or parallel evolution. The evolution of adhesive toepads in geckos remains understudied because of the pau...

Alpine ecosystems harbour a rich and highly specialised biodiversity, which is particularly susceptible to anthropogenic disturbances such as habitat loss and fragmentation as well as to climate change. Combined with other forms of land‐use conversion, construction and maintenance of ski resorts can have severe consequences on alpine biodiversity....

Increase of fly maggot disease (myiasis) in anurans in North Rhine-Westphalia? Since 2017, there have been 137 new myiasis records in amphibians in NRW. These are presented in a new distribution map. Myiasis was detected in 162 of 1260 grid squares (12.9 %), a significant increase compared to the data collected until 2017 (8.7 % at that time). The...

Context Functional connectivity models are essential in identifying major dispersal pathways and developing effective management strategies for expanding populations of invasive alien species. However, the extrapolation of models parameterized within current invasive ranges may not be applicable even to neighbouring areas, if the models are not bas...

The Spotted Softshell Turtle (Pelodiscus variegatus) has been recognised since 2019 from Vietnam and Hainan Island, China, but little information about its population status and distribution range is currently available. The species has been provisionally listed as Critically Endangered by the Turtle and Tortoise Working Group, although the status...

Once distributed all over the Philippines, the endemic Philippine Crocodile (Crocodylus mindorensis) is nowadays threatened with extinction. It is estimated that less than 140 mature individuals live in the wild. Human activities like fishing and poaching, as well as land-use change and habitat conversion cause a continuing threat to the remaining...

Climate change has been suggested as an important human-induced driver for the ongoing sixth mass extinction. As a common response to climate change, and particularly global warming, species move toward higher latitudes or shift uphill. Furthermore, rapid climate change impacts the biotic interactions of species, particularly in the case of Zygaeni...

Adaptive radiations garner considerable interest from evolutionary biologists. Lizard radiations diversifying along structural niche space often exhibit distinct changes in body and limb proportions. One prediction is that terrestrial species inhabiting open habitats will have relatively longer hindlimbs, associated with faster running speeds, whil...

Weather conditions are important factors determining the activity, and consequently detection probability of animals. Especially in ectotherms from temperate habitats, activity can vary strongly depending on weather. The sand lizard Lacerta agilis is a wide-ranging lizard that is often subject to environmental impact assessments due to its proximit...

The objective of this research was to assess the genetic diversity and phylogeography of Bombus terrestris and examine the historical events that shaped its contemporary genetic structures using the COI mitochondrial marker. Specimens of the species were collected from its distribution range alongside the Alborz Mountain range, and GenBank sequence...

Justified predictions of future changes in species distributions are necessary for defining adequate conservation plans over space and time. The Marsh or Mugger Crocodile (Crocodylus palustris) is native to freshwater habitats of the In-dian subcontinent and in southeastern Iran. Habitat loss is currently the most important threat to crocodile disp...

Monitoring of wildlife populations is essential for their conservation and requires a carefully chosen methodology. We compared survey effectiveness of reptiles using coverboards and visual encounter surveys in two study sites in the Italian Alps with similar habitats and reptile communities. The two sites shared similar methodologies, cover boards...

In this study, we morphologically examine larval specimens of Ranitomeya variabilis, which were breed in captivity and genetically determined to belong to the French Guiana population. We provide detailed data on the external morphology, chondrocranium, cranial muscle systems and inner organs of the tadpoles. Additionally, we provide essential char...

Background Ecomorphological studies of lizards have increasingly employed comparison of claw morphology among species in relation to spatial niche use. Typically, such studies focus on digit IV of the autopodia, especially the pes. Uniformity of claw morphology among digits is more often implicitly assumed than tested. Results Using four species o...

Since the world is currently in the midst of a major biodiversity crisis, scientists have assigned high conservation priority to 36 biodiversity hotspots around the world. As part of one of the leading hotspots in terms of species richness and local endemism, Vietnam is considered a country with high conservation priority. The reptile fauna of Viet...

Turtles and tortoises are one of the world's most threatened vertebrates; more than half of the 352 currently rec-ognised species are threatened. To implement the IUCN CPSG's One Plan Approach to Conservation, we herein analyse the available information from the Zoological Information Management System (ZIMS) to provide an overview of the species a...

According to the One Plan Approach to Conservation, proposed by the IUCN SSC Conservation Planning Specialist Group (CPSG), there is, besides in situ conservation measures, also increased need for ex situ conservation breeding of threatened taxa. To gain a better overview of the current situation, we have compiled information from the zoo databases...

A solid basis to address the conservation challenges of amphibians requires an increased knowledge on their natural history and biology. Recent data on reproductive modes in amphibians suggest that they are much more complex and variable than previously thought but understudied. However, detailed information on the reproductive history is especiall...

Climate change has been suggested as an important human-induced driver for the ongoing sixth mass extinction. As a common response to climate change, and particularly global warming, species move toward higher latitudes or shift uphill. Furthermore, rapid climate change impacts the biotic interactions of species. Especially, in Zygaenid moths which...

In this study we morphologically examine larval specimens of Ranitomeya variabilis , which were breed in captivity and genetically determined to belong to the French Guiana population. We provide detailed data on the external morphology, chondrocranium, cranial muscle systems and inner organs of the tadpoles. Additionally, we provide essential char...

Der Glatte Krallenfrosch (Xenopus laevis) wurde lange Zeit häufig von Aquarianern, Apothekern und Wissenschaftlern gehalten. Diese Beliebtheit hat allerdings leider dazu geführt, dass der einst nur im südlichen Afrika verbreitete Zungenlose Frosch (Familie Pipidae) nun auf fünf Kontinenten zu finden ist und dort großen Schaden an den heimischen Öko...

The relict, endemic taxa Allopaa and Chrysopaa are key elements of the Hindu Kush–Himalayan amphibian fauna and potentially share a similar biogeographic evolution, making them important proxies for the reconstruction of the palaeoenvironmental and palaeotopographic history of the Himalaya–Tibet–Orogen. However, little is known about the taxonomy,...

Given the high degrees of adaptation to specific microhabitats and restricted-range endemism, Goniurosaurus (Tiger geckos) serves as a unique model to study the complex evolution in lizards. Using phylogenetic analyses, we estimated the first divergence date of Goniurosaurus to the Eocene (~ 45.3 mya). The diversification within four monophyletic s...

Global warming threatens the viability of tropical coral reefs and associated marine calcifiers, including symbiont‐bearing larger benthic foraminifera (LBF). The impacts of current climate change on LBF are debated because they were particularly diverse and abundant during past warm periods. Studies on the responses of selected LBF species to chan...

The relict, endemic taxa Allopaa and Chrysopaa are key elements of the Hindu Kush-Himalayan amphibian fauna and potentially share a similar biogeographic evolution, making them important proxies for the reconstruction of the palaeoenvironmental and palaeotopographic history of the Himalaya-Tibet-Orogen. However, little is known about the taxonomy,...

We investigated for which threatened endemic Malagasy bird species zoo populations already exist, and which threatened species are not yet covered by ex situ conservation measures. To gain an overview of Malagasy bird species held in zoos, the number of individuals kept, the number of keeping institutions and successful reproduction within the last...

Many ecological questions can be answered only with data from hundreds or even thousands of individuals. In some taxonomic groups, such as snakes, the availability of those data is rare due to low population densities and/or the difficulties in collecting them. Hence, studies on the population structure of snakes are still relatively scarce compare...

The mossy frogs of the genus Theloderma Tschudi comprise 28 described taxa (Sivongxay et al. 2016; Frost 2022), which are distributed from north-eastern India and Myanmar to southern China, across the peninsula of Indochina and Malaysia, to Indonesia (Poyarkov et al. 2015; Frost 2022). Theloderma albopunctatum is a small-sized taxon that is assigne...

The distribution and occurrence of a species in its habitat are inevitably linked to its ecology. To successfully monitor and protect species, it is important to investigate which species-specific factors influence its interactions with the environment. In this study, we focus on patterns in habitat use of the Sand Lizard (Lacerta agilis). Differen...

Habitat loss can increase the susceptibility of individuals to parasitic infections, and hence, parasite load can serve as an early warning indicator of stress before the persistence of a population becomes threatened. In this study, we tested the effects of patch characteristics, isolation and landscape composition resulting from habitat loss on t...

Correlative species distribution modelling (SDM) can be a useful tool to quantify a species’ realized niche and to predict its potential distribution for non-native ranges. The agamid lizard Calotes versicolor s.l. belongs to the most widely distributed reptile taxa worldwide. In the past, C. versicolor s.l. has been introduced to several countries...

The current decline in global biodiversity is most evident in amphibians with 41% percent of all species worldwide classified as threatened with extinction. Hence, a major challenge in amphibian conservation is the high number of threatened species, leading to a common approach of identifying priority species and regions for conservation efforts. A...

Madagascar is home to 370 native amphibian and 420 native reptile species with an extraordinary high endemism rate of approx. 98%. Less than half (39%) of Madagascar’s amphibian and less than a third (32%) of Madagascar’s reptile species are currently evaluated as threatened by the IUCN (2021). We investigated for which threatened endemic Malagasy...

Human impact is considered the major threat to the global decline of biodiversity, especially for threatened endemic species in karst ecosystems. Studies assessing a species' demography based on temporal and spatial indicators of population size, density and structure are expected to evaluate the level of impact of threats and are therefore becomin...

Natural history collections are constituted of a wide variety of biological specimens preserved around the world.They represent a continuous source of knowledge and play a fundamental role in the synthesis on the diversity, composition, distribution, and conservation of species. Paul Müller (1940–2010) was a German zoologist who collected amphibian...

Understanding animal space use and habitat needs is a vital requirement for effective conservation and management measures. Considering the multiple instances in which landscapes are anthropogenically altered, it becomes increasingly important to understand what the spatial requirements of an animal are. However, smaller animals, like lizards, requ...

The Lichtenfelder’s Tiger Gecko, Goniurosaurus lichtenfelderi is currently known only from northern Vietnam and southern China. Because of its restricted distribution, the species is potentially threatened by extinction due to anthropogenic impacts. Recently, the species has been listed in the IUCN Red List of Threatened Species as “Vulnerable” and...

Detailed information on potentially suitable habitats and forecasted alterations thereof under climate change scenarios are critical for the conservation planning of endangered taxa, in particular those with small distribution ranges. The Huu Lien Tiger Gecko, Goniurosaurus huuliensis, is a is a micro-endemic species in northern Vietnam. The specie...

Conservation status of Crocodylus palustris throughout its range, threats by climate change, human crocodile conflicts, ecology, need for research. Crocodile Specialist Group Newsletter, 40 (3): 12-20

A working group focusing on the conservation of the mugger (Crocodylus palustris) has been established.

In previous studies, the superhydrophilic skin of moisture-harvesting lizards has been linked to the morphological traits of the lizards’ integument, that is, the occurrence of honeycomb-shaped microstructures. Interestingly, these structures can also cover the skin of lizards inhabiting wet habitats. We therefore tested the influence of the micros...

Species distribution models (SDMs) are frequently used to characterise current, past or future realised environmental niches. Two recent studies applied different approaches to infer range dynamics in eastern subspecies of the spur-thighed tortoise Testudo graeca Linnaeus, 1758. We discuss differences in the conclusions of the two papers and use mu...

Aim The biogeographic history of the Sahara-Sahel desert is tightly linked to its extreme and fluctuating palaeoclimate and diverse topography. For the mesic species inhabiting the region, coastal areas and the Nile Valley are perceived as the main pathways to disperse through desert habitats, but past connections may have also occurred throughout...

Abstract To manage populations of threatened species according to the IUCN’s One Plan Approach, knowledge about both in situ and ex situ populations is required. To enhance the conservation of threatened skinks and to gain an overview which skink species are kept in zoos, and thus already have an ex situ conservation component, we analysed data fro...

Climate change impacts biodiversity and is driving range shifts of species and populations across the globe. To understand the effects of climate warming on biota, long-term observations of the occurrence of species and detailed knowledge on their ecology and life-history is crucial. Mountain species particularly suffer under climate warming and of...

Based on the species specificity of anuran vocalization, bioacoustics can be utilized in terms of species identification and species delimitation. The genus Theloderma comprises 23 to 29 species, depending on inclusion of the (sub)genera Nyctixalus and Stelladerma, from which the majority of 14 species was described in this century. In spite of num...

Home range and habitat selection are key subjects when studying animal ecology. Defining the space use and resource management of an animal establishes a solid basis for further behavioural and ecological research, as well as conservation management. Studies focusing on determining home range and habitat selection often include further questions re...

The pathways of introduction of non-native amphibians are diverse, as historically amphibians were used as pest control agents, food stock, or were introduced to perform research. Today, the pet trade is the main source for amphibian introductions into novel ranges. However, these introductions mainly concern anurans, whereas cases involving urodel...