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opennotspecifiedMar 2020View details →

FIGURE 8 in A new potentially endangered limestone-associated Bent-toed Gecko of the Cyrtodactylus pulchellus (Squamata: Gekkonidae) complex from northern Peninsular Malaysia

FIGURE 8. (A) Image of the limestone mining quarry on the North side of the type locality (Cement quarry 1 in Figure 7). (B) Image of the type locality, Gunung Baling, Kedah. (C) Image of the limestone mining quarry on the south side of the type locality (Cement quarry 2 in Figure 7).

opencc-zeroApr 2020View details →

Supplementary material 1 from: McPartland JM, Small E (2020) A classification of endangered high-THC cannabis (Cannabis sativa subsp. indica) domesticates and their wild relatives. PhytoKeys 144: 81-112. https://doi.org/10.3897/phytokeys.144.46700

A classification of endangered high-THC cannabis (Cannabis sativa subsp. indica) domesticates and their wild relatives

opencc-zeroJul 2020View details →

Data from: When to stay and when to leave? Proximate causes of dispersal in an endangered social carnivore

1. Reliable estimates of birth, death, emigration, and immigration rates are fundamental to understanding and predicting the dynamics of wild populations and, consequently, inform appropriate management actions. However, when individuals disappear from a focal population, inference on their fate is often challenging. 2. Here we used 30 years of individual-based mark-recapture data from a population of free-ranging African wild dogs (Lycaon pictus) in Botswana and a suite of individual, social, and environmental predictors to investigate factors affecting the decision to emigrate from the pack. We subsequently used this information to assign an emigration probability to those individuals that were no longer sighted within their pack (i.e. missing individuals). 3. Natal dispersal (i.e. emigration from the natal pack) showed seasonal patterns with female dispersal peaking prior to the mating season and male dispersal peaking at the beginning of the wet season. For both sexes, natal dispersal rate increased in the absence of unrelated individuals of the opposite sex in the pack. Male natal dispersal decreased with increasing number of pups in the pack and increased in larger packs. Female natal dispersal decreased with increasing number of pups in larger packs, but increased with increasing number of pups in smaller packs. Individuals of both sexes were less likely to exhibit secondary dispersal (i.e. emigration from a pack other than the natal pack) if they were dominant and if many pups were present in the pack. 4. Our models predicted that 18% and 25% of missing females and males, respectively, had likely dispersed from the natal pack, rather than having died. A misclassification of this order of magnitude between dispersal and mortality can have far-reaching consequences in the evaluation and prediction of population dynamics and persistence, and potentially mislead conservation actions. 5. Our study showed that the decision to disperse is context-dependent and that the effect of individual, social, and environmental predictors differs between males and females and between natal and secondary dispersal related to different direct and indirect fitness consequences. Furthermore, we demonstrated how a thorough understanding of the proximate causes of dispersal can be used to assign a dispersal probability to missing individuals. Knowledge of causes of dispersal can then be used within an integrated framework to more reliably estimate mortality rates.

opencc-zeroAug 2020View details →

Data from: Restricted connectivity and population genetic fragility in a globally endangered hammerhead shark

Vagile, large-bodied marine organisms frequently have wide range dispersion but also dependence on coastal habitats for part of their life-history. These characteristics may induce complex population genetic structure patterns, with resulting implications for the management of exploited populations. The scalloped hammerhead, Sphyrna lewini, is a cosmopolitan, migratory shark in tropical and warm temperate waters, inhabiting coastal bays during parturition and juvenile development and the open ocean as adults. Here, we investigated the genetic connectivity and diversity of S. lewini in the western Atlantic using large sample coverage (N=308), and data from whole mitochondrial control region (mtCR) sequences and ten nuclear microsatellite loci. We detected significant population genetic structure with both mtCR and microsatellites markers (mtCR: ΦST = 0.60; p < 0.001; microsatellites: Dest 0.0794, p = 0.001, FST = 0.046, p < 0.05), and isolation by distance (mtCR r = 0.363, p = 0.009; microsatellites r = 0.638, p = 0.007). The migration and gene flow patterns, based on mtCR and microsatellites were asymmetric, and female reproductive philopatry is postulated to explain such population subdivision patterns. The notable population differentiation at microsatellites markers indicates low-levels of male-mediated gene flow in the western Atlantic. The overall effective population size was estimated as 299 (215 – 412 Confidence Interval), and there was no evidence of strong or recent bottleneck effects. Findings of at least three management units, moderate genetic diversity, and low effective population size in the context of current overfishing calls for intensive management aimed at short and long-term conservation for this endangered species in the western Atlantic Ocean.

opencc-zeroAug 2020View details →

Comparative population genetics of the federally endangered Relict Darter, and its sister taxon the Clarks Darter (Teleostei: Percidae)

The southeastern United States harbors one of the most diverse temperate freshwater fish faunas of the world. Unfortunately, due to improper land use practices and habitat degradation, many of the species in this region are imperiled and may become extinct without appropriate conservation efforts. This study examined the population dynamics of an endangered endemic darter of southwest Kentucky, the Relict Darter (Etheostoma chienense) and its sister taxon, the undescribed Clarks Darter (Etheostoma cf. oophylax). Mitochondrial sequence data coupled with SNP data were used to infer population structure, gene flow, genetic variation, and effective population sizes of both species. The results from this study, based on 160 individuals from nine localities, indicate that the endangered Relict Darter possesses limited genetic variation based on mitochondrial DNA haplotypes (N=4). In addition, SNP data (6.8k markers) further indicates limited genetic structure (K=1), as well as a low effective population size (143-918), suggesting that the Relict Darter can be managed as a single, panmictic conservation unit. It is suggested that conservation efforts be taken to protect remaining habitats, augment the system with artificial spawning substrates, and, as a last resort (if needed), supplement the natural population with captive reared individuals. Ethesotoma cf. oophylax showed some genetic variation among distant sites, but more samples are needed throughout the range in order to fully understand the population dynamics of this species.

opencc-zeroSep 2020View details →

Data from: Chloroplast population genetics reveals low levels of genetic variation and conformation to the central–marginal hypothesis in Taxus wallichiana var. mairei, an endangered conifer endemic to China

The central–marginal hypothesis predicts that geographically peripheral populations should exhibit reduced genetic diversity and increased genetic differentiation than central populations due to smaller effective population size and stronger geographical isolation. We evaluated these predictions in the endangered conifer Taxus wallichiana var. mairei. Eight plastid simple sequence repeats (cpSSRs) were used to investigate plastid genetic variation in 22 populations of Taxus wallichiana var. mairei, encompassing nearly its entire distribution range. Low levels of plastid genetic variation and differentiation were detected in the populations, and the findings were attributed to low mutation rates, small population sizes, habitat fragmentation and isolation, and effective pollen or seed dispersal. Hunan and Hubei were identified as major refugia based on the number of private haplotypes and species distribution modeling. Trends in plastid genetic diversity and genetic differentiation from central to peripheral populations supported the predictions of the central–marginal hypothesis. In scenarios wherein the future climate becomes warmer, we predict that some peripheral populations will disappear and southern and southeastern regions will become significantly less habitable. Factors that include the levels of precipitation during the driest month, annual precipitation level, and annual temperature range will be decisive in shaping the future distribution of these populations. This study provides a theoretical basis for the conservation of T. wallichiana var. mairei.

opencc-zeroOct 2020View details →

Intraspecific competition drives dispersal of an endangered ibis data

Although dispersal drives population dynamics and species distribution, we still know little about how it affects the dynamic of endangered and restricted-range species. After 1981, when the last seven wild individuals of Crested Ibis were discovered in China, the species remained confined to a single location ('original nesting area') until 2000 (< 24 breeding pairs). Then, the breeding population began a significant spatial and numerical expansion (toward the 'secondary nesting area'). Our analyses of long-term (1993–2017) individual-based data (n = 193) show that: (i) natal, but not breeding dispersal, was common (≈77% and ≈2.1%); (ii) as predicted by the intraspecific competition hypothesis, the probability of natal dispersal from the original nesting area increased with increasing and decreasing density at the birthplace and the first breeding site, respectively; nonetheless, (iii) in the secondary nesting area, birth dispersal was density-independent, but (iv) from here they were more likely to disperse, pointing to weak competition at these breeding areas and, since they were all born to dispersing parents, to a role for individual personality; (v) the Weibull distribution provided the best fit to the observed dispersal distances, indicating the presence of long-distance dispersers. We expect the Crested Ibis to continue to spread throughout the region if the protection programs cover a wide range to allow long-distance dispersal. Overall, our study suggests that intraspecific competition can cause dispersal in a population of few individuals confined to a small area and, therefore, be critical for the recovery and expansion of an endangered species.

opencc-zeroNov 2020View details →

Data from: Development and testing of an environmental DNA (eDNA) assay for endangered Atlantic sturgeon to assess its potential as a monitoring and management tool

Significant declines in Atlantic sturgeon (Acipenser oxyrhynchus oxyrhynchus) abundances along the US east coast have spurred major research efforts and management actions over the last 50 years, yet information on spawning stock abundances and habitat use is still lacking for many river systems, including in the Chesapeake Bay, USA. Here, we developed and tested a new quantitative PCR (qPCR) assay to detect Atlantic sturgeon environmental DNA (eDNA) in water samples with the goal of providing an alternative method to monitor presence and relative abundance. We also examined Atlantic sturgeon eDNA shedding rates in laboratory experiments. A qPCR-probe assay targeting Cytochrome-B was developed and showed no amplification of other related and co-occurring fishes. Pond trials at a density of ~0.2 g/L sturgeon produced relatively strong eDNA detections (~1,000-25,000 copies/L) in all seven water samples assayed. Water samples taken from two river systems in the Chesapeake Bay produced zero eDNA detections in the summer, while fall sampling during sturgeon spawning produced positive eDNA detections in 26% of samples, though at much lower concentrations (400-1,800 copies/L) compared with the pond (mesocosm) detections. Acoustic detections of sturgeon near river sampling sites were positively associated with eDNA detections. However, the eDNA assay failed to detect the presence of sturgeon in some samples when abundances were very low or when fish were in deep water. Finally, Atlantic sturgeon eDNA shedding rates were estimated to be on the order of estimates for other fish species, which suggests that relatively weak detections in the field are not necessarily driven by low rates of eDNA shedding. Overall, eDNA analysis represents a promising new monitoring tool for Atlantic sturgeon. Applying these methods in other rivers along the US east coast is an important next step in documenting Atlantic sturgeon distribution for management and conservation purposes.

opencc-zeroDec 2020View details →

Supplementary material 1 from: Guedes GHS, Salgado FLK, Uehara W, de Pavia Ferreira DL, Araújo FG (2020) The recapture of Leptopanchax opalescens (Aplocheiloidei: Rivulidae), a critically endangered seasonal killifish: habitat and aspects of population structure. Zoologia 37: 1-8. https://doi.org/10.3897/zoologia.37.e54982

Figure S1. Photographic records of Leptopanchax opalescens in an aquarium after three hours of capture (Photos 1–3), and record of a male specimen with more exuberant color immediately after capture in its natural habitat (Photos 4–5). Date: March 19th, 2020; Coordinates: 22°42.35'S, 43°41.59'W.

opencc-zeroDec 2020View details →

Preference, performance, and chemical defense in an endangered butterfly using novel and ancestral host plants

Adoption of novel host plants by herbivorous insects can require new adaptations and may entail loss of adaptation to ancestral hosts. We examined relationships between an endangered subspecies of the butterfly Euphydryas editha (Taylor's checkerspot) and three host plant species. Two of the hosts (Castilleja hispida, Castilleja levisecta) were used ancestrally while the other, Plantago lanceolata, is exotic and was adopted more recently. We measured oviposition preference, neonate preference, larval growth, and secondary chemical uptake on all three hosts. Adult females readily laid eggs on all hosts but favored Plantago and tended to avoid C. levisecta. Oviposition preference changed over time. Neonates had no preference among host species, but consistently chose bracts over leaves within both Castilleja species. Larvae developed successfully on all species and grew to similar size on all of them unless they ate only Castilleja leaves (rather than bracts) which limited their growth. Diet strongly influenced secondary chemical uptake by larvae. Larvae that ate Plantago or C. hispida leaves contained the highest concentrations of iridoid glycosides, and iridoid glycoside composition varied with host species and tissue type. Despite having largely switched to a novel exotic host and generally performing better on it, this population has retained breadth in preference and ability to use other hosts.

FIGURES 24–25 in Description of the immature stages of the endangered Japanese endemic Oreodytes kanoi (Kamiya, 1938) (Coleoptera: Dytiscidae: Hydroporinae) and comparison with the known larvae of Oreodytes Seidlitz, 1887

FIGURES 24–25. Oreodytes kanoi (Kamiya, 1938), pupa: (24) dorsal aspect; (25) ventral aspect. A, male; B, female. Scale bar = 1 mm.

FIGURES 19–23 in Description of the immature stages of the endangered Japanese endemic Oreodytes kanoi (Kamiya, 1938) (Coleoptera: Dytiscidae: Hydroporinae) and comparison with the known larvae of Oreodytes Seidlitz, 1887

FIGURES 19–23. Oreodytes kanoi (Kamiya, 1938), instar III: (19) head capsule, dorsal aspect (colour pattern not represented); (20–21) prothoracic leg, (20) anterior aspect; (21) posterior aspect; (22) last abdominal segment, dorsal aspect; (23), urogomphus, dorsal aspect. Scale bars = 0.5 mm.

FIGURES 5–6 in Description of the immature stages of the endangered Japanese endemic Oreodytes kanoi (Kamiya, 1938) (Coleoptera: Dytiscidae: Hydroporinae) and comparison with the known larvae of Oreodytes Seidlitz, 1887

FIGURES 5–6. Oreodytes kanoi (Kamiya, 1938), instar I, head capsule: (5) dorsal aspect (colour pattern not represented); (6) ventral aspect. EB, egg bursters; TP, tentorial pits. Numbers and lowercase letters refer to primary setae and pores, respectively. Scale bar = 0.1 mm.

FIGURES 1–4 in Description of the immature stages of the endangered Japanese endemic Oreodytes kanoi (Kamiya, 1938) (Coleoptera: Dytiscidae: Hydroporinae) and comparison with the known larvae of Oreodytes Seidlitz, 1887

FIGURES 1–4. Oreodytes kanoi (Kamiya, 1938): (1) instar II, dorsal habitus; (2) instar III, dorsal habitus; (3) pupa. A, dorsal aspect; B, lateral aspect; C, ventral aspect; (4) adult. A, male, dorsal habitus; B, female, dorsal habitus; C, median lobe of aedeagus, lateral aspect; D, paramere, lateral aspect. Scale bars = 0.5 mm in (1–2, 4C–D), 1 mm in (3, 4A–B).

FIGURES 14–18 in Description of the immature stages of the endangered Japanese endemic Oreodytes kanoi (Kamiya, 1938) (Coleoptera: Dytiscidae: Hydroporinae) and comparison with the known larvae of Oreodytes Seidlitz, 1887

FIGURES 14–18. Oreodytes kanoi (Kamiya, 1938), instar I: (14–15) metathoracic leg, (14) anterior aspect; (15) posterior aspect; (16–17) last abdominal segment, (16) dorsal aspect; (17) ventral aspect; (18) urogomphus, dorsal aspect. Numbers and lowercase letters refer to primary setae and pores, respectively; filled squares refer to additional setae and pores. Scale bars = 0.1 mm.

FIGURES 26–29 in Description of the immature stages of the endangered Japanese endemic Oreodytes kanoi (Kamiya, 1938) (Coleoptera: Dytiscidae: Hydroporinae) and comparison with the known larvae of Oreodytes Seidlitz, 1887

FIGURES 26–29. Habitats of larvae and pupae of Oreodytes kanoi (Kamiya, 1938): (26) Tôshichi Onsen, Iwate Prefecture, small stream; (27) habitat of pupae; (28) prepupa; (29) pupa in case. Scale bars = 1 mm.

FIGURES 7–13 in Description of the immature stages of the endangered Japanese endemic Oreodytes kanoi (Kamiya, 1938) (Coleoptera: Dytiscidae: Hydroporinae) and comparison with the known larvae of Oreodytes Seidlitz, 1887

FIGURES 7–13. Oreodytes kanoi (Kamiya, 1938), instar I, head appendages: (7–8) antenna, (7) dorsal aspect; (8) ventral aspect; (9–10) maxilla, (9) dorsal aspect; (10) ventral aspect; (11–12) labium, (11) dorsal aspect; (12) ventral aspect; (13) mandible, dorsal aspect. Numbers and lowercase letters refer to primary setae and pores, respectively. Scale bar = 0.1 mm.

opennotspecifiedOct 2020View details →

FIGURE 2 in A description of the tadpole of the Critically Endangered Botsford's leaf-litter frog (Leptobrachella botsfordi) with comments on the distribution and conservation status of the species

FIGURE 2. Tadpoles of Leptobrachella botsfordi in life. A and B, lateral views of VNMN 010898 and VNMN 010899 (Stage 25 and 26 respectively); C and D, body dorsal and ventral view of VNMN 010898; E and F, body dorsal and ventral view of VNMN 010899; G, unvouchered specimen at Stage 44 (total length 32.4 mm) in life. Scale bar in A–F is 0.5 cm.