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Narrow-ranging species are usually omitted from Species distribution models (SDMs) due to statistical constraints, while they are predicted to be particularly vulnerable to climate change. The recently available high-resolution environmental predictors, along with recently developed methods enable to increase the eligibility of narrow-ranging species for SDMs, provided their distribution is well known. We fill a gap of knowledge on the effect of predicted climate change on narrow-ranging species. We modelled the distribution of the golden mantella frog Mantella aurantiaca and the Manapany day gecko Phelsuma inexpectata, for which the distribution of their occurrence records is well documented. Our modelling scheme included a range of processes susceptible to address statistical issues related to narrow-ranging species. We predict an alarming decline in climate suitability in the whole current distribution area of both species by 2070, potentially leading to a complete extinction in most scenarios. We identified the areas with the best climate suitability in the future, but these remain largely suboptimal regarding species climatic niche. The high level of habitat fragmentation suggests that both species likely need to be at least partly translocated. Climate change may not only drive range contractions or distribution shifts in narrow-ranging species, but may lead to the complete extirpation of suitable environments across their entire region. This study suggests that the level of threats of narrow-ranging species already identified as threatened may be underestimated, especially in heterogeneous tropical areas. We stress the need to develop sampling campaigns and implement proactive actions for narrow-ranging species in the tropics.

Research on threatened species in zoos can provide vital information to inform conservation planning and implementation in the field. This is particularly important for rare and cryptic species with behavior patterns that are difficult to observe in the wild. The Critically Endangered golden mantella (Mantella aurantiaca) is an iconic, endemic frog confined to mid‐altitude subhumid forest in Moramanga District, Madagascar. Ecological and behavioral data for this highly threatened species are sparse, and conservation work will need to be informed by both in situ and ex situ research on behavior and habitat preferences. This study utilized environmental information gathered in the field to design a system where behavior and microhabitat use could be measured in captivity. Using replicated climatically controlled chambers (the "Froggotrons"), we analysed the 24‐h activity profile of the golden mantella in relation to temperature and humidity. Golden mantellas showed a bimodal pattern of activity during the day with much less activity during the night. Frogs kept at warmer temperatures (20–25°C) were more active than those kept under cooler conditions (16–19°C). However, the bimodal pattern was retained under the different temperatures, although the second peak occurred slightly earlier under warmer conditions. Most activity was observed when humidity levels were above 85%, although less than half of the mantellas were active outside leaf microhabitats during peak periods. These findings can inform ongoing field surveys through determining the optimum times of day to either capture or count golden mantellas for further conservation actions. Highlights: Golden mantellas displayed bimodal activity during daytime.The activity rhythm was influenced by temperature and humidity."Froggotrons" allow observations of behavior of cryptic species that may not be possible in the wild. [ABSTRACT FROM AUTHOR]

The article discusses the morphological description of spindly leg syndrome (SLS) in Golden Mantella frog. Topics discussed include developmental disorder SLS of frog which is asymmetric limb deformities and atrophy of the muscles, the role of genetics and trauma in the SLS disease, and characterisation of SLS by abnormalities in the limb development of metamorphosing tadpoles.

Seventy skins of three mantellid frog species from Madagascan swamp-forest habitats, Mantella aurantiaca, M. crocea, and M. milotympanum, were individually examined for skin alkaloids using GC/MS. These poison frogs were found to differ significantly in their alkaloid composition from species of Mantella originating from non-flooded rainforest in eastern Madagascar, which were examined in earlier work. Only 16 of the previously detected 106 alkaloids were represented among the 60 alkaloids from the swamp-forest frogs of the present study. We hypothesize this difference is related mainly to habitat but cannot exclude a phylogenetic component as the three swamp-forest species are a closely related monophyletic group. The paucity of alkaloids with unbranched-carbon skeletons (ant-derived) and the commonness of alkaloids with branched-carbon skeletons (mite-derived) indicate that oribatid mites are a major source of alkaloids in these species of mantellids. Furthermore, most of the alkaloids have an oxygen atom in their formulae. Differences in alkaloids were observed among species, populations of the same species, and habitats. In M. aurantiaca, small geographic distances among populations were associated with differences in alkaloid profiles, with a remote third site illustrating even greater differences. The present study and an earlier study of three other mantellid species suggest that oribatid mites, and not ants, are the major source of alkaloids in the species of mantellids examined thus far. [ABSTRACT FROM AUTHOR]

Age structure of populations of four species of endemic Malagasy frogs of the genus Mantella (M. aurantiaca, M. baroni, M. bernhardi, M. madagascariensis) was examined by skeletochronology based on 96 specimens from nine different localities. In more than half of these (57%), no lines of arrested growth (LAGs) were found, and the number of LAGs recognized in the remaining specimens was mostly one, and probably two in three specimens. It is generally considered that each LAG corresponds to one year of life; our results therefore confirm that in Mantella populations almost all specimens are in their first or second year of life. [ABSTRACT FROM AUTHOR]

Mantella aurantiaca is a small, bright orange, terrestrial amphibian that is endemic to the island of Madagascar. The species has attracted significant attention from herpetologists and captive breeders but relatively little effort has been given to its conservation in the wild. We surveyed 33 reported breeding localities of the species to determine sites of conservation importance and aspects of habitat use and seasonality. We found a total of 471 M. aurantiaca in 26 different localities, all of which were characterised by intact or degraded humid forest on sloping ground alongside temporary lentic ponds in narrow valleys. Additional monitoring at a single site revealed that adult M. aurantiaca predominantly used the ponds and surrounding humid forest habitat during the austral summer and moved upslope at the beginning of the austral winter. Effective conservation for this species should therefore include measures to safeguard both forest and aquatic habitat features. Although 62% of localities occurred in sites with a positive conservation status (provisional protected areas or Ramsar sites), there is currently heavy pressure from artisanal mining, logging and agriculture in these areas. Because a further 15% of sites occur on land due to be impacted by mining and an additional 23% were at sites without any biodiversity management, the future of M. aurantiaca in the wild is precarious. A species conservation strategy is therefore needed to produce a cohesive plan for the future which aims to secure as many sites as possible for conservation. [ABSTRACT FROM AUTHOR]