Cyanosis by methemoglobinemia in tadpoles of Cochranella granulosa (Anura: Centrolenidae)

Tadpoles inhabit generally well oxygenated rivers and streams, nevertheless they were found in areas with limited oxygen availability inside the rivers. To assess this feature, I examined factors that influence centrolenid tadpole behaviour using Cochranella granulosa. The tadpoles were reared in well-oxygenated and hypoxic environments and their development, survivorship and growth were compared. The tadpoles in oxygenated water acquired a pale color, while tadpoles in hypoxic water grew faster and were bright red and more active. In the oxygenated water, the ammonium, which had its origin in the tadpoles' urine and feces, was oxidized to nitrate. In contrast, in the hypoxic treatment, the nitrogen compounds remained mainly as ammonium. Presumably, the nitrate in oxygenated water was secondarily reduced to nitrite inside the long intestine coils, because all symptoms in the tadpoles point to methemoglobinemia, which can occur when the nitrite passes through the intestine wall into the bloodstream, transforming the hemoglobin into methemoglobin. This could be checked by a blood test where the percentage of methemoglobin was 2.3% in the blood of tadpoles reared in hypoxic condition, while there was a 19.3% level of methemoglobin in the blood of tadpoles reared in oxygenated water. Together with the elevated content of methemoglobin, the growth of the tadpoles was delayed in oxygenated water, which had high nitrate content. The study about quantitative food-uptake showed that the tadpoles benefit more from the food in hypoxic water, although they spent there more energy moving around than the tadpoles living in oxygenated but nitrate-charged water.     

Rediscovery of Hyalinobatrachium chirripoi (Anura: Centrolenidae) in southeastern Costa Rica

The Suretka glass frog, Hyalinobatrachium chirripoi, has been recently rediscovered in the southeastern region of Costa Rica. This species was last reported in Costa Rica in the 1950's. H. chirripoi is distinguished from H. colymbiphyllum, which appears to be its most closely Costa Rican related taxon, by having extensive webbing between fingers II-III.     

Feeding Ecology and Regurgitation–Reingestion Behavior of the Critically Endangered Indri indri in the Maromizaha Protected Area,Eastern Madagascar

International Journal of Primatology - Deforestation around the world is a major threat to primates. Understanding primate species’ habitat and dietary requirements is critical in creating...     

Fine scale gene flow and individual movements among subpopulations of Centrolene prosoblepon (Anura: Centrolenidae)

Dispersal capabilities determine and maintain local gene flow, and this has implications for population persistence and/or recolonization following environmental perturbations (natural or anthropogenic), disease outbreaks, or other demographic collapses. To predict recolonization and understand dispersal capacity in a stream-breeding frog, we examined individual movement patterns and gene flow among four subpopulations of the Neotropical glassfrog, Centrolene prosoblepon, at a mid-elevation cloud forest site at El Copé, Panama. We measured male movement directly during a two year mark-recapture study, and indirectly with gene flow estimates from mitochondrial DNA sequences (mtDNA). Individuals of this species showed strong site fidelity: over two years, male frogs in all four headwater streams moved very little (mean = 2.33 m; mode = 0 m). Nine individuals changed streams within one or two years, moving 675-1,108 m. For those males moving more than 10 m, movement was biased upstream (p < 0.001). Using mtDNA ND1 gene sequences, we quantified gene flow within and among headwater streams at two spatial scales: among headwater streams within two adjacent watersheds (2.5 km2) and among streams within a longitudinal gradient covering 5.0 km2. We found high gene flow among headwater streams (phi(ST) = 0.007, p = 0.325) but gene flow was more limited across greater distances (phi(CT) = 0.322, p = 0.065), even within the same drainage network. Lowland populations of C. prosoblepon potentially act as an important source of colonists for upland populations in this watershed.     

Batrachochytrium dendrobatidis Infection in the Recently Rediscovered Atelopus mucubajiensis (Anura, Bufonidae), a Critically Endangered Frog from the Venezuelan Andes

The harlequin frog, Atelopus mucubajiensis, is a critically endangered species that was believed to be extinct until 2004, when a single adult female was found in the Venezuelan Andes. Its disappearance after 1994 has been attributed to an increase in the prevalence of the fungal pathogen, Batrachochytrium dendrobatidis, in populations of these frogs. Using histology and Real-Time PCR assays, we tested this adult female positive for B. dendrobatidis. We report for the first time, to our knowledge, infection in a live specimen of A. mucubajiensis. The presence of this pathogen in remaining individuals poses a problem for the long-term persistence of this critically endangered species, as new epidemic episodes of chytridiomycosis could jeopardize the survival of remnant populations.     

A new species of frog of the genus Hyalinobatrachium (Anura: Centrolenidae) of the Delta of the Orinoco River,Venezuela

A new species of Hyalinobatrachium of the fleischmanni group, H. mondolfii, is described from the Orinoco delta floodplains in Venezuela. This new species can be distinguished from other congeners by the following combination of characters: parietal peritoneum clear, pericardium white, visceral and hepatic peritoneum white, color in life pale green with diminute yellow spots and, in preservative, cream with small dark melanophores (visible only under magnification), bones white in life, extense webbing, snout round in dorsal view and inclinate in lateral view, dorsal skin granulate and a advertisement call with a fundamental frequency greater than 5000 Hz.     

Micropropagation of Withania coagulans (Stocks) Dunal: A Critically Endangered Medicinal Herb

An efficient micropropagation protocol has been developed for Withania coagulans, a highly endangered medicinal herb and an important natural source of withanolides. Prolific multiplication of axillary buds occurred from the nodal segments taken from adult plant, and cultured on MS medium enriched with BA (0.5 mg l^?1), Kn (0.5 mg l^?1) and PG (0.5 mg l^?1). Nodal segments and shoot tips of elongated microshoots also behaved the same way in cultures and formed multiple shoots through axillary bud multiplication. Addition of PG (0.5 mg l^?1) in the regeneration medium significantly improved induction and elongation of shoot buds. Elongated shoots were placed on filter paper bridges soaked in MS medium with CC (10 mg l^?1) and PG (0.5 mg l^?1) for the initial 7 days’ pulse treatment and thereafter, they were transferred to rooting medium containing IBA (0.25 mg l^?1) + PAA (0.5 mg l^?1) + CC (2 mg l^?1). This protocol has the capacity of producing 1000 plants from one nodal segment after 4 subcultures of 2 weeks each.     

Diverse grouping and mating strategies in the Critically Endangered Hainan gibbon (Nomascus hainanus)

Primates - Understanding flexibility in the social structure and mating strategies of the world’s last remaining population (35 individuals) of wild Hainan gibbons (Nomascus hainanus) is...     

The Breeding Ecology of a Critically Endangered Salamander,Hynobius amjiensis(Caudata:Hynobiidae),Endemic to Eastern China

Hynobius amjiensis is a critically endangered salamander species(IUCN Red List) endemic to eastern China. It currently has three known populations: one in Longwangshan, Zhejiang Province(type locality), and two in Qingliangfeng between Anhui and Zhejiang Provinces. We examined the relatively unstudied breeding ecology of this species in the field and at laboratory from March 2007 to May 2014. Adult males and females were year-round terrestrial, except for the February–April breeding season. During this period, we captured only a total of 16 breeding adults(11 males and 5 females). As few as 100 breeding females were estimated based on the number of egg sacs observed since 2007. This number was significantly reduced from the estimated number between 1992 and 1998. Males(mean total length = 16.21 cm, mean body mass = 18.8 g) were slightly smaller than females(16.51 cm, 19.2 g). Size of breeding pools ranged from 0.2 m~2 to 1.2 m~2(0.1–1.2 m depths). Each female deposits a pair of egg sacs by attaching the adhesive tips of the sacs to aquatic plants or dead twigs. Fifteen pairs of egg sacs had an average length of 28.6 cm and a diameter of 3.3 cm. On average, each egg sac contained 75 eggs with a diameter of 0.3 cm. Our field survey revealed that H. amjiensis used oviposition sites in small, cool, and weakly acidic pools at high elevations(1 300–1 600 m) where peat moss was abundant. Reduction in wetland size and disappearance of suitable breeding pools suggest that this salamander species is under threat of extinction, particularly at Longwangshan, where 5 of the 9 breeding pools have either dried up or disappeared. Combined size of the remaining 4 pools is less than 2 m~2. We urge immediate implementation of more effective conservation measures and suggest that preservation priority should be given to habitat that contains suitable breeding pools.     

极度濒危植物-云南蓝果树的种子形态和不同处理条件对种子萌发的影响

观察了云南蓝果树(Nyssa yunnanensis)种子的形态,并初步研究了萌发基质、光照、人工破坏内果皮和pH梯度碱液处理对云南蓝果树种子萌发的影响。结果表明:云南蓝果树种子(带内果皮)平均大小为0.94cm×0.52cm×0.17cm(长×宽×厚),千粒重约234.3g,有萌发瓣;红土/腐殖土/泥炭土(v/v/v,1∶1∶1)为云南蓝果树种子萌发的适宜基质;种子在光、暗条件下都能萌发;人工破坏内果皮能明显地提高种子的萌发率;碱液处理对云南蓝果树种子的萌发有抑制作用,但对中国蓝果树(N.sinensis)种子的萌发有促进作用。本文还对云南蓝果树的致濒原因进行了讨论。     

High Genetic Diversity and Population Differentiation in the Critically Endangered Plant Species Trailliaedoxa gracilis (Rubiaceae)

Trailliaedoxa gracilis W. W. Smith et Forrest (Rubiaceae), a Chinese endemic monotypic genus belonging to the Alberteae (Rubiaceae), exhibits a narrow distribution in the dry valleys of the Jinsha River and Red River drainage area in southwestern China. The few sites at which T. gracilis occurs are fragmented and isolated, and several are highly vulnerable to human disturbance. As T. gracilis is a protected plant with a second-degree national priority, the genetic diversity and structure of the populations of this species should be investigated to determine the most suitable conservation strategy. In this study, two chloroplast regions and one nuclear region were used to investigate the genetic diversity, genetic structure, and demographic history of T. gracilis. We observed a high total genetic diversity (H _T?=?0.952 and 0.966) and low average within-population diversity (H _S?=?0.07 and 0.489) based on cpDNA and nDNA analyses. Thus, a strong genetic structure (F _ST?=?0.98049 and 0.59731) was detected. A phylogeographic structure was detected by nuclear DNA analysis (N _ST?>?G _ST, P?<?0.05); however, the chloroplast data did not show a significant phylogeographic structure (N _ST?<?G _ST, P?>?0.05). The Bayesian skyline plot and isolation with migration analysis were used to estimate the demographic history of T. gracilis. The results indicated that a marked bottleneck effect occurred during the glacial-interglacial of the Pleistocene. Among the extant populations of T. gracilis, the population found in ChunJiang, LuQuan, and YuXi showed the highest haplotype diversity based on cpDNA sequences and should be given priority for protection. According to the nDNA analysis, every population presented a high level of diversity and a high content of private haplotypes. Therefore, every population should be protected.

     

Introgression Threatens the Survival of the Critically Endangered Freshwater Crayfish Cherax tenuimanus (Decapoda: Parastacidae) in the Wild

Hybridization and genetic introgression following the introduction of exotic species can pose a significant threat to the survival of geographically restricted species. A remnant population of the critically endangered freshwater crayfish Cherax tenuimanus in the upper reaches of the Margaret River in southwestern Australia is under threat following the introduction and spread of its congener Cherax cainii. Here, we examine the extent of hybridization and introgression between the two species using twelve polymorphic microsatellite loci. Our study reveals there are three times more C. cainii than C. tenuimanus at our study site in the upper reaches of the Margaret River. There is also evidence of hybridization and introgression between C. tenuimanus and C. cainii at this site, with F₁, F₂ and backcrossed individuals identified. While interbreeding was confirmed in this study, our simulations suggest that the levels of introgression are much lower than would be expected under random mating, indicating partial reproductive barriers exist. Nevertheless, it is apparent that hybridization and introgression with C. cainii pose a serious threat to C. tenuimanus and their survival in the wild will require active adaptive management and continued genetic monitoring to evaluate management effectiveness.     

Characterization of 10 trinucleotide microsatellite loci in the Critically Endangered Pyrenean yam Borderea chouardii (Dioscoreaceae)

The low levels of allozymic variability found in the Critically Endangered Borderea chouardii prompted us to develop microsatellite markers to assess the genetic variability and population structure for the adequate conservation management of this species. A (CTT)_n‐enriched partial genomic library was constructed. Ten polymorphic microsatellite loci were isolated from it, rendering 51 alleles in 47 individuals analysed. The allelic pattern observed for all of the loci with more than two alleles suggests that B. chouardii is tetraploid.     

Ecological and Geographical Analysis of the Distribution of the Mountain Tapir (Tapirus pinchaque) in Ecuador: Importance of Protected Areas in Future Scenarios of Global Warming

In Ecuador, Tapirus pinchaque is considered to be critically endangered. Although the species has been registered in several localities, its geographic distribution remains unclear, and the effects of climate change and current land uses on this species are largely unknown. We modeled the ecological niche of T. pinchaque using MaxEnt, in order to assess its potential adaptation to present and future climate change scenarios. We evaluated the effects of habitat loss due by current land use, the ecosystem availability and importance of Ecuadorian System of Protected Areas into the models. The model of environmental suitability estimated an extent of occurrence for species of 21,729 km² in all of Ecuador, mainly occurring along the corridor of the eastern Ecuadorian Andes. A total of 10 Andean ecosystems encompassed ~98% of the area defined by the model, with herbaceous paramo, northeastern Andean montane evergreen forest and northeastern Andes upper montane evergreen forest being the most representative. When considering the effect of habitat loss, a significant reduction in model area (~17%) occurred, and the effect of climate change represented a net reduction up to 37.86%. However, the synergistic effect of both climate change and habitat loss, given current land use practices, could represent a greater risk in the short-term, leading to a net reduction of 19.90 to 44.65% in T. pinchaque’s potential distribution. Even under such a scenarios, several Protected Areas harbor a portion (~36 to 48%) of the potential distribution defined by the models. However, the central and southern populations are highly threatened by habitat loss and climate change. Based on these results and due to the restricted home range of T. pinchaque, its preference for upland forests and paramos, and its small estimated population size in the Andes, we suggest to maintaining its current status as Critically Endangered in Ecuador.     

Reproductive and Stress Response Hormones of the Critically Endangered Southern Muriqui (Brachyteles arachnoides: Atelidae) Under Captive Conditions

International Journal of Primatology - The Convention on Biological Diversity and the International Union for Conservation of Nature emphasize that ex situ conservation efforts are unavoidable....     

No Correlation Between Heterozygosity and Vegetative Fitness in the Narrow Endemic and Critically Endangered Clematis acerifolia (Ranunculaceae)

The relationship between heretozygosity and vegetative fitness was explored in the narrow endemic and threatened Clematis acerifolia (Ranunculaceae), both at individual and population levels. The relationships between fitness, habitat factors, and population size were also analyzed. Allozyme electrophoresis was used to quantify the levels of heterozygosity of nearly 200 surveyed individuals belonging to the nine extant populations of this species. Six parameters of vegetative fitness were measured: plant height, shrub diameter, length of the largest leaf, width of the largest leaf, mean number of leaves/stem, and total number of stems. The percentage of tree cover (light availability) was measured as an indicator of habitat quality. A principal component analysis reduced the original fitness variables to two uncorrelated principal components. None of these correlated significantly with both heterozygosity and population size, in contrast to the expected result. Nevertheless, one of the principal components showed a positive relationship with light availability, which may indicate that habitat quality may have significant effects on the performance of this species. Thus, to ensure the viability of this endangered species, maintenance of adequate habitat quality (by avoiding further fragmentation) may be more important than maximizing genetic diversity within populations.     

Phylogenetic relationships of glassfrogs (Centrolenidae) based on mitochondrial and nuclear genes

Glassfrogs (family Centrolenidae) represent an exceptionally diverse group among Neotropical anurans, but their evolutionary relationships never have been assessed from a molecular perspective. Mitochondrial and nuclear markers were used to develop a novel hypothesis of centrolenid phylogeny. Ingroup sampling included 100 terminals, with 78 (53%) of the named species in the family, representing most of the phenotypic diversity described for the group. Thirty-five species representing taxa traditionally associated with glassfrogs were used as outgroups. Gene sampling consisted of complete or partial sequences of three mitochondrial (12S, 16S, ND1) and three nuclear markers (c-myc exon 2, RAG1, POMC) for a total of 4362 bp. Phylogenies were estimated using maximum parsimony, maximum likelihood, and Bayesian analyses for individual genes and combined datasets. The separate analysis of mitochondrial and nuclear datasets allowed us to clarify the relationships within glassfrogs; also, we corroborate the sister-group relationship between Allophryne ruthveni and glassfrogs. The new phylogeny differs significantly from all previous morphology-based hypotheses of relationships, and shows that hypotheses based on few traits are likely to misrepresent evolutionary history. Traits previously hypothesized as unambiguous synapomorphies are shown to be homoplastic, and all genera in the current taxonomy (Centrolene, Cochranella, Hyalinobatrachium, Nymphargus) are found to be poly- or paraphyletic. The new topology implies a South American origin of glassfrogs and reveals allopatric speciation as the most important speciation mechanism. The phylogeny profoundly affects the traditional interpretations of glassfrog taxonomy, character evolution, and biogeography—topics that now require more extensive evaluation in future studies.