Potential Candidate Species Research Articles

Sensitivity of Alabama Freshwater Gastropod Species to Nickel Exposure.

Snails are effective bioindicators due to their prolific distribution, high level of endemism, and capacity to accumulate contaminants. Freshwater snails have unique ecological niches which are imperiled by land-use change and the introduction of hazardous chemicals. To assess how environmental alterations affect gastropods, lab-based studies are needed to characterize the toxicity of specific stressors. This can help guide policy decisions and remediation efforts. The aim of this research was to characterize acute toxicity of nickel (Ni) on endemic snails (Somatogyrus georgianus [Walker, 1904], Elimia cahawbensis [Lea, 1861], and Elimia spp.) and measure the accumulation of Ni and mineral elements including calcium (Ca), magnesium, potassium, and sodium (Na). Snails were exposed to six concentrations (25-800 µg/L) of Ni for 96 h. Among the studied snail species, E. cahawbensis was the most sensitive to Ni, with the lowest lethal concentration where 50% of the organisms died (LC50) at 88.88 µg/L Ni after 96 h. The LC50 at 96 h for S. georgianus was 167.78 µg/L Ni, and 393.13 μg/L Ni for Elimia spp. Except for Elimia spp., mortality of the other two snail species corresponded to the whole-body uptake of Ni. Nickel exposure also influenced Ca and Na uptake for Elimia spp. All three endemic species are potential candidate species for evaluating localized effects of human activities, and the present study provides a first step in characterizing how snails would be affected by environmental alterations. More research could further characterize potential effects of other human stressors on these endemic snail species. Future research into subindividual responses and routes of exposure can further elucidate variations in species sensitivity. Environ Toxicol Chem 2024;00:1-11. © 2024 SETAC. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.

Induced spawning, larval rearing, and innate diet analysis of Indian black clam, Villorita cyprinoides: An alternative to resource restoration through aquaculture

Villorita cyprinoides (Gray, 1825) also called the Indian black clam is a native species from the Indian peninsula directly related to the livelihood of many beneficiaries. The wild population of this Cyrenid clam is confronted with substantial challenges, including various climatic stressors and anthropogenic pressures such as overfishing and habitat destruction. A balance between capture fisheries and aquaculture through the development of hatchery technology is inevitable for ensuring the sustainable use of resources. The declining population of V. cyprinoides underscores the urgency of standardizing breeding protocols and implementing proper farming practices to foster a sustainable black clam fishery, given that Villorita is a potential candidate species for aquaculture. This paper describes the first successful induced spawning of the clam with successful rearing of larvae up to the umboned veliger stage and evaluates the efficacy of induced spawning through combined physical and chemical stimuli. Furthermore, our study employs eDNA metabarcoding to analyze plankton dynamics in waters from native clam beds. This sheds light on the potential microalgal dietary preferences of the species, which can be valuable in preparing diets for larval development and aquaculture in the future.

Diversity, Distribution, and Habitat Association of Anuran Species from Keffa, Southwest Ethiopia

The aim of the current study was to provide a description of the species composition and habitat association of anuran species found in the Keffa area of southwest Ethiopia, among the least studied natural areas in Ethiopia. Data were gathered in both the rainy and dry seasons. Opportunistic observations, audio, and visual encounters were used to perform the survey. To capture different frog species, drift fence and pitfall trap techniques were used. Three habitat types—wetlands, agricultural land, and riverine forests—were explored for the frog species. A total of 3672-person field hours were spent and 5678 individuals of 26 different anuran species from eight different families were recorded. Of these, six species were new records for the Keffa area. Species determination was assessed using morphology and validated with genetic barcoding. The mitochondrial 16S rRNA and COI gene sequence analysis have been used in molecular systematic analyses of the frog species. The Leptopelis ragazzii that was discovered to be present in the earlier study was actually Leptopelis vannutellii, as evidenced by DNA sequencing. The Hyperolius individuals were initially categorized as H. nasutus, but after conducting DNA barcoding, they were found to be H. microps. At least three potential new candidate species (Leptopelis sp. 1, Leptopelis sp. 2, and Phrynobatrachus sp. 1) were discovered. Hyperoliidae was the most abundant family from the recorded anurans, followed by Phrynobatrachidae, while Conrauidae was the least abundant. Most species were found in the wetland habitat, followed by riverine forest, while agricultural land had the least. Wetlands had the highest values for the Shannon diversity index (2.131), followed by agricultural land (1.58) and riverine forests (1.459). The environmental variables revealed that temperature had a considerable negative impact, while precipitation had a non-significantly positive relationship with anuran abundance. The Keffa area is rich in frog species, accounting for 35% of the country’s batrachofauna. However, the habitats have been fragmented and ruined by agricultural expansion, water drainage from the wetlands, and the conversion of horticulture to field crops. We recommend that non-governmental organizations, districts, regional officials, and local people in and around Keffa actively engage in wetland and forest conservation and protection.

Phytostabilization of trace elements and 13C isotope composition of Atriplex atacamensis Phil. cultivated in mine tailings treated with organic amendments.

Mining generates large quantities of mineral processing wastes that are typically stored in mine tailings (MT) ponds. Long-term exposure of the surrounding areas to the material from the tailings ponds has been reported to have adverse effects on both human health and the environment. The purpose of this study was to evaluate the ability of Atriplex atacamensis Phil. to phytostabilize metals (Cu, Fe, Mn, and Zn) and sulfur (S) when grown directly on mine tailings with and without compost (C) and humic substance (HS). The stress status of A. atacamensis Phil. was also evaluated through the 13C isotopic composition of bulk leaves. A 120-day greenhouse experiment was conducted and three treatments were evaluated: (i) MT without any amendments (control), (ii) MT + C (dose: 89 ton ha-1), and (iii) MT + HS (0.72 ton ha-1). Mine tailings material exhibited low salinity, alkaline pH, high extractable S-SO4 concentrations, and low fertility; total Fe, Mn, and Zn concentrations were within the reference range for mine tailings, but total Cu concentrations were high at 1860 ± 236mgkg-1. The HS had higher pH, EC, CEC, and available concentrations of N, P, and K than compost, while S-SO4 concentrations were similar in both amendments. 13C NMR analysis showed that the HS contained more alkyl, aromatic, and phenolic groups, while the compost was dominated by O-alkyl and carboxyl groups. At the end of the experiment, the MT + C treatment achieved a significant decrease in Cu, Fe, and Mn concentrations in the roots and aboveground parts of A. atacamensis Phil. and an increase in Zn values in both tissues. Both amendments increased the sulfur content in the aboveground parts, while metal concentrations under the HS treatment proved similar to control. Furthermore, the δ13CV-PDB values obtained in this study indicate that the organic amendments did not cause additional physiological stress to the plants compared to the MT treatment. Overall, A. atacamensis Phil. was shown to have the ability to phytostabilize metals and sulfur, making it a potential candidate species for in situ evaluation of the phytostabilization process on mine tailings.

Self-Domestication Underground? Testing for Social and Morphological Correlates of Animal Personality in Cooperatively-Breeding Ansell’s Mole-Rats (Fukomys anselli)

Ansell’s mole-rats (Fukomys anselli) are sexually dimorphic subterranean rodents that live in families consisting of a single breeding pair and their late-dispersing non-breeding offspring. Most individuals exhibit a conspicuous white head patch, which results from integumental depigmentation. Alongside other morphological, physiological, and social characteristics, skin depigmentation in these social rodents mirrors traits that presumably evolved as byproducts from selection against aggression in domestic animals, making them a potential candidate species for a self-domesticated wild mammal. Here we explored whether the expression of the white head patch, sexual dimorphism, and reproductive division of labor are reflected by different personalities in Ansell’s mole-rats. We tested locomotory activity and risk-taking as well as aggression and affiliative behavior in 51 individuals originating from nine captive families in various experimental set-ups. In line with the concept of animal personality, we recovered consistent individual responses over time. While sex had no influence on any tested variable, reproductive status was found to affect risk-taking behavior but not other personality dimensions. Discriminant function analysis revealed that family members clustered more closely together than expected by chance, suggesting that group affiliation rather than sex or social status determines behavioral profiles in this species. Finally, we failed to recover any consistent correlation between head patch expression and behavior, which conflicts with predictions of the self-domestication hypothesis. We argue that many domestication-like traits in Ansell’s mole-rat and its congeners evolved in the framework of subterranean adaptation and call for a cautious application of the self-domestication concept to wild mammals.

Quantitative selection of focal birds and mammals in higher-tier risk assessment: An application to rice cultivations.

European Pesticide Registration requires a risk assessment (RA) for nontarget organisms according to EU Regulation. European Authorities have developed Guidance Documents (GDs) for RA considering exposure scenarios for the required organisms typical for terrestrial crops. The “Birds and Mammals EFSA GD” allows using multiple sources of information to extract information on species frequency needed in identifying focal species for higher‐tier RA. We developed an analytical framework to calculate species frequency according to availability of species and habitat quantitative data. Since the exposure scenarios reported in the EFSA GD are inconsistent for rice, we tested the method on birds and mammals in a portion of the largest rice‐cultivated area of Europe, the Italian Po floodplain. We derived three lists of focal species: (a) an expert‐based list based on land‐use data only, which can be useful for a preliminary exploration of potential candidate species; (b) a list derived from the interpolation of species data only, which reflects actual species frequency in rice fields; and (c) a list obtained by a species distribution model based on species monitoring and land‐use data, which account for species selectivity for rice crops and are transferable to other contexts. Focal species were identified for crop‐specific diet‐foraging guilds, to build specific exposure scenarios to assess the risk from pesticides application in rice fields. The partial differences between our lists and those previously proposed highlight the need for identifying national lists, which can vary according to study area, biogeographic region and exposure scenarios. The application of the proposed method in European rice‐producing countries should lead to crop‐specific lists, which could then be integrated to obtain a flexible European list applicable to higher‐tier RA. Integr Environ Assess Manag 2022;18:1020–1034. © 2021 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

The effect of interactions between soil compaction and phenol contamination on plant growth characteristics: Implications for scaling bioremediation at industrial sites

In phenol contaminated soils from an industrial site, soil compaction and soil chemical contaminants influenced germination, emergence, and early plant growth (roots and shoots) for Thrift (Ameria maratima) and Blackbutt oats (Avena sativa). The specific effects were of soil compaction (low, 100 psi and high, 800 psi) at two concentrations of phenol (biotreated, ∼200 mg kg−3; untreated, ∼1150 mg kg−3). Plant responses to compaction and phenol varies between the two species. Emergence of Thrift showed greater sensitivity to increasing soil compaction but only under high phenol concentrations. Low phenol inhibited Thrift root length, as is the case with Balckbutt oats, although high phenol had no significant impact on Thrift. While shoot length of Blackbutt oats is not significantly affected by increasing soil compaction, it is negatively impacted at the increased phenol concentrations in the untreated soils indicating an interaction effect with compaction. This is the first study that examines the impact of soil contamination on oats. The oat variety tested had known drought tolerance and hardiness indicating an ability to withstand compaction, and which may explain those characteristics. Thrift was most resistant to contamination which is consistent with its previously reported tolerance of pollutants. Implications of the study are that Blackbutt oats represent a potential candidate species for land rehabilitation under high compaction conditions such as at degraded soil sites at decommissioned mining operations, polluted industrial sites, or degraded (compacted) agricultural land.

Diversity of ACE2 and its interaction with SARS-CoV-2 receptor binding domain.

COVID-19, the clinical syndrome caused by the SARS-CoV-2 virus, has rapidly spread globally causing hundreds of millions of infections and over two million deaths. The potential animal reservoirs for SARS-CoV-2 are currently unknown, however sequence analysis has provided plausible potential candidate species. SARS-CoV-2 binds to the angiotensin I converting enzyme 2 (ACE2) to enable its entry into host cells and establish infection. We analyzed the binding surface of ACE2 from several important animal species to begin to understand the parameters for the ACE2 recognition by the SARS-CoV-2 spike protein receptor binding domain (RBD). We employed Shannon entropy analysis to determine the variability of ACE2 across its sequence and particularly in its RBD interacting region, and assessed differences between various species' ACE2 and human ACE2. Recombinant ACE2 from human, hamster, horseshoe bat, cat, ferret, and cow were evaluated for RBD binding. A gradient of binding affinities were seen where human and hamster ACE2 were similarly in the low nanomolar range, followed by cat and cow. Surprisingly, horseshoe bat (Rhinolophus sinicus) and ferret (Mustela putorius) ACE2s had poor binding activity compared with the other species' ACE2. The residue differences and binding properties between the species' variants provide a framework for understanding ACE2-RBD binding and virus tropism.

Plotting for change: an analytical framework to aid decisions on which lineages are candidate species in phylogenomic species discovery

Abstract A recent study argued that coalescent-based models of species delimitation mostly delineate population structure, not species, and called for the validation of candidate species using biological information additional to the genetic information, such as phenotypic or ecological data. Here, we introduce a framework to interrogate genomic datasets and coalescent-based species trees for the presence of candidate species in situations where additional biological data are unavailable, unobtainable or uninformative. For de novo genomic studies of species boundaries, we propose six steps: (1) visualize genetic affinities among individuals to identify both discrete and admixed genetic groups from first principles and to hold aside individuals involved in contemporary admixture for independent consideration; (2) apply phylogenetic techniques to identify lineages; (3) assess diagnosability of those lineages as potential candidate species; (4) interpret the diagnosable lineages in a geographical context (sympatry, parapatry, allopatry); (5) assess significance of difference or trends in the context of sampling intensity; and (6) adopt a holistic approach to available evidence to inform decisions on species status in the difficult cases of allopatry. We adopt this approach to distinguish candidate species from within-species lineages for a widespread species complex of Australian freshwater fishes (Retropinna spp.). Our framework addresses two cornerstone issues in systematics that are often not discussed explicitly in genomic species discovery: diagnosability and how to determine it, and what criteria should be used to decide whether diagnosable lineages are conspecific or represent different species.

The role of Sahara highlands in the diversification and desert colonization of the Bosc's fringe‐toed lizard

AbstractAimThe 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 currently isolated mountain regions. Herein, we test the trans‐Sahara mountain corridor hypothesis (i.e., mesic connectivity across Central Sahara highlands) and its role in the diversification of a small terrestrial vertebrate.LocationNorth Africa and Arabia.TaxonAcanthodactylus boskianus (Squamata: Lacertidae).MethodsWe integrated multi‐locus mitochondrial and nuclear phylogenies with species’ climate‐niche modelling, including palaeo‐projections. Genetic analyses aimed to assess the species’ genetic structure, identify its main mitochondrial lineages and nuclear diversity, and reconstruct its ancestral biogeography. Species’ climate‐niche stability was modelled independently for the Late Pleistocene‐Holocene and the Plio‐Pleistocene, to infer historical climatic refugia and dispersal corridors.ResultsFour spatially structured mitochondrial lineages, integrating several parapatric sub‐lineages, originated during the Plio‐Pleistocene. Nuclear data revealed nine potential candidate species. Climatic refugia were located in mountains and desert fringes, remaining consistent for the Late Pleistocene‐Holocene and the Plio‐Pleistocene. Recurrent North‐South climatic corridors were located along the desert periphery, while others less frequent were found across Central Sahara. Ancestral biogeography analyses recovered a recent Pleistocene colonization of the Sahel throughout eastern Sahara and either Sahara or Sahel origin for Central Sahara populations.Main conclusionsSpecies’ diversification was triggered by a combination of Plio‐Pleistocene climatic cycles across a complex topographic region, where mountains acted as the main diversification hotspots. The historical role of Central Sahara highlands as main non‐peripheral mesic refugia was corroborated. In addition, intermittent climatic connections linked Mediterranean and Sahel ecoregions with Central Sahara refugia, suggesting the existence of alternative trans‐Sahara dispersal routes to the putative coastal and Nile corridors.

First linkage maps and a pilot QTL analysis for early growth performance in common dentex (Dentex dentex) and sharpsnout seabream (Diplodus puntazzo)

Two potential candidate species for the Mediterranean aquaculture–the common dentex (Dentex dentex) and the sharpsnout seabream (Diplodus puntazzo)-are used in the present study in order to depict their genetic architecture for the first time. We have constructed the first linkage maps for both species using SNP markers derived from ddRAD sequencing. The quality of the maps produced was verified from comparative analysis with the most studied and phylogenetically related sparid species, the gilthead sea bream (Sparus aurata). A high genetic similarity was detected, based on the high number of alignments of the two new species against the reference genome of the gilthead seabream. Furthermore, a pilot study for QTL analysis per species was performed using phenotypic measurements at the juvenile stage (approximately 2 g) and revealed putative genomic areas which affect juvenile growth performance. One of those areas was located close to a candidate gene (ANGPTL6 gene) which affects growth performance. The present study improves our knowledge on the genetic architecture of those two species by presenting not only the first linkage maps, but also by providing some indications for growth performance QTL. The results can be used as a starting point to initiate further research for the genetic improvement of these two new species.

Generalist carnivores can be effective biodiversity samplers of terrestrial vertebrates

Biodiversity conservation relies on effective practical methods for assessing species occurrences and distributions, particularly for elusive species. Generalist carnivores are widely distributed and relatively abundant predators with broad dietary ranges, and as such could potentially serve as “biodiversity samplers” of sympatric prey communities. To test this hypothesis, we analyzed leopard cat (Prionailurus bengalensis) and red fox (Vulpes vulpes) diets to survey local vertebrate communities in several mountainous areas in China. Fecal DNA metabarcoding analysis revealed that leopard cat prey from five mountain ranges across China included 99 vertebrate taxa representing 12 taxonomic orders and red fox prey from two of those mountain ranges displayed a similar degree of diversity, which was highly correlated with local species records accrued by traditional survey methods. Our results show that diet metabarcoding analysis of generalist carnivores can be an effective, noninvasive, and economically viable tool for biodiversity monitoring to inform management decisions. In addition, we explored selection criteria and potential candidate species for carnivore sampler‐based biodiversity studies in other parts of the world.

Nutritional evaluation, bioconversion performance and phylogenetic assessment of black soldier fly (Hermetia illucens, Linn. 1758) larvae valorized from food waste

The black soldier fly ( H. illucens ) is a potential candidate species for the sustainable bioconversion of organic matter that endorses the concept of a circular economy. The nutritional evaluation of black soldier fly larvae (BSFL) reared in a food waste bioconversion system revealed a crude protein content of 41.44 ± 0.17 g/100g and crude lipid content of 35.69 ± 0.24 g/100g. Among the mineral content in BSFL, Ca (22.95 ± 0.91 g/kg) was present in the highest concentration, followed by P (5.47 ± 0.06 g/kg) and K (4.78 ± 0.081 g/kg). The fatty acid profile of BSFL oil showed a higher level of saturated fatty acids than unsaturated, with the highest level of lauric acid (C12:0). Vitamins such as retinol, vitamin D 3 , α -tocopherol, β -tocopherol, and γ -tocopherol were detected in larval oil. α -tocopherol was present in the highest concentration (80.39 ± 4 . 02 μ g/g). The bioconversion performance of BSFL in terms of various parameters such as biomass yield, bioconversion efficiency, substrate reduction, and nutritional composition was evaluated. The bio-waste to larvae conversion ratio was 6.80, with a bioconversion efficiency of 24.31 ± 0.62 %. The overall substrate reduction by BSFL was 72.38 ± 1.37 %. In addition to amplification of mitochondrial partial COI gene for larval identification, comparative and phylogenetic analyses were performed. The phylogenetic analysis revealed that the specific haplotypic populations from Palaearctic, Oriental, Afrotropic, Australasian, and Nearctic biogeographic realms establish a closer relationship or single ancestral origin with the Indian haplotypes, which is probably associated with anthropogenic factors resulting in the cosmopolitan distribution of this new world originated wide-spectrum fly. • First report on bioconversion of food waste using black soldier fly larvae from India • Food waste was transformed into aqua/ animal feed ingredients and compost • One of the gateway attempts to solve the issues on organic waste disposal in India • Phylogenetic assessment of black soldier fly larvae including the Oriental region

First onboard fertilization of Asian seabass, Lates calcarifer: Effects of egg stocking density on the fertilization, hatching and survival rate

Asian seabass, Lates calcarifer is a highly valuable and potential candidate species for mariculture. The objectives of the present study were to conduct an onboard fertilization trail to produce viable offspring and see the effects of stocking density of eggs on the fertilization, hatching and survival rate of Asian seabass juveniles. Eggs and sperm were collected during the full moon in May 2019 from the Moheshkhali channel estuary, the Northeast Bay of Bengal, by hand stripping method. Pooled sperm from two males and eggs from a female were used for insemination. Three egg stocking densities (T1- 37 40,000 eggs/batch; T2- 60,000 eggs/batch and T3- 80,000 eggs/batch) was used for this study. The one-way ANOVA (p < 0.05) showed significant effects of egg stocking density on fertilization, hatching success, and survival rate of Asian seabass larvae. The maximum fertilization and hatching success of Asian seabass eggs were 83.05 ± 2.22 and 76.51 ± 1.19%, respectively, achieved with 40,000 eggs/batch stocking density. The highest survival rate was observed in treatment 1 (56.25 ± 3.97%) at 30 DPH, which was significantly different from the other treatments (p < 0.05). Our results indicated that eggs of Asian seabass with a lower stocking density (40,000 eggs/batch) could achieve higher success in fertilization, hatching and survival compared to higher stocking densities (60,000 eggs/batch and 80,000 eggs/batch, respectively). Results from this study could be useful for assisted breeding of Asian seabass in captivity.

Identifying potential candidate Culicoides spp. for the study of interactions with Candidatus Cardinium hertigii.

Culicoides biting midges (Diptera: Ceratopogonidae) are vectors responsible for the transmission of several viruses of veterinary importance. Previous screens of Culicoides have described the presence of the endosymbiont Candidatus Cardinium hertigii (Bacteroidetes). However, any impacts of this microbe on vectorial capacity, akin to those conferred by Wolbachia in mosquitoes, are yet to be uncovered and await a suitable system to study Cardinium-midge interactions. To identify potential candidate species to investigate these interactions, accurate knowledge of the distribution of the endosymbiont within Culicoides populations is needed. We used conventional and nested PCR assays to screen Cardinium infection in 337 individuals of 25 Culicoides species from both Palearctic and Afrotropical regions. Infections were observed in several vector species including C. imicola and the Pulicaris complex (C. pulicaris, C.bysta, C. newsteadi and C. punctatus) with varying prevalence. Phylogenetic analysis based on the Gyrase B gene grouped all new isolates within 'group C' of the genus, a clade that has to date been exclusively described in Culicoides. Through a comparison of our results with previous screens, we suggest C. imicola and C. sonorensis represent good candidates for onward study of Cardinium-midge interactions.

Sıcaklık Değişimlerinin Ostrakod (Crustacea) Türlerinin Mekansal Dağılımı ve Ekolojisi Üzerine Etkisi

To understand the possible effects of changes in ambient temperature on spatial distribution and ecology of ostracods, samples were randomly collected from 70 aquatic sites with 12 different habitat types from Hatay (Turkey) province during the summer season of 2012. 14 of 19 ostracod species were newly reported for the province. The first two axes of CCA explained 79.7% of the cumulative variance of the relationship between the 12 most common species and five environmental variables. Accordingly, water temperature and electrical conductivity were the most effective factors on species occurrences (p&amp;lt;0.05). Estimating ecological optimum and tolerance values of species revealed that Herpetocypris chevreuxi and Cypridopsis vidua displayed the lowest and highest tolerance values for water temperature, respectively. TWINSPAN results illustrated that ostracod species can be used to determine characteristics of habitat conditions. Indeed, the co-occurrence of H. chevreuxi with one or more cosmopolitan species is the indication of an increase in salinity and temperature values. Results suggested that temperature changes can cause critical alteration in shallow water bodies where species with lower ecological tolerances will eventually be negatively affected. Therefore, such species, which may be called “potential candidate species for local extinction” will either be eliminated from the habitats in short term or become extinct in long term.

Phylogenetics of mud snakes (Squamata: Serpentes: Homalopsidae): A paradox of both undescribed diversity and taxonomic inflation

Mud snakes (Serpentes: Homalopsidae) are a family of 55 described, mainly aquatic, species primarily distributed throughout mainland Southeast Asia and the Indo-Australian Archipelago. Although they have been the focus of prior research, the basic relationships amongst genera and species remain poorly known. We used a combined mitochondrial and nuclear gene dataset to infer their phylogenetic relationships, using the highest levels of taxon and geographic sampling for any homalopsid phylogeny to date (62% generic and 62% species coverage; 140 individuals). Our results recover two reciprocally monophyletic groups: the fangless Brachyorrhos and its sister clade comprised of all rear-fanged homalopsids. Most genera and interspecific relationships were monophyletic and strongly supported, but intergeneric relationships and intraspecific population structure lack support. We find evidence of both undescribed diversity as well as cases of taxonomic inflation within several species. Tree-based species delimitation approaches (mPTP) support potential new candidate species as distinct from their conspecifics and also suggest that many named taxa may not be distinct species. Divergence date estimation and lineage-through-time analyses indicate lower levels of speciation in the Eocene, with a subsequent burst in diversification in the Miocene. Homalopsids may have diversified most rapidly during the Pliocene and Pleistocene, possibly in relation to tectonic shifts and sea-level fluctuations that took place in Sundaland and the Sahul Shelf. Our analyses provide new insights on homalopsid taxonomy, a baseline phylogeny for the family, and further biogeographic implications demonstrating how dynamic tectonics and Quaternary sea level changes may have shaped a widespread, diverse family of snakes.

Bird alpha, beta and functional diversities across three peri-urban woodland stands along an anthropogenic disturbance gradient: is formal protection a guarantee for ecological integrity?

Urban woodlands are significant as refugia for species of wild birds which contribute to provisioning a wide range of ecological services beneficial to nature and to humans. Due to the increasingly small and fragmental structure of these habitats, arising from constant expansion of city infrastructure, these birds are in increasing conservation peril with serious ramifications to the ecological and touristic values they represent. We assessed the alpha, beta and functional diversities of birds in three small woodland stands within the metropolis of Nairobi, Kenya and compared their variations along an anthropogenic disturbance gradient (Low, Moderate; High) based on relative openness, vegetation cover and rate of human visitation. Birds were surveyed using timed species counts during six sampling periods and grouped into three diet-guilds and three vertical foraging strata to assess compositional and assemblage turnover responses to disturbance. Functional overlaps in birds’ ecological roles were also evaluated, and potential candidate species for monitoring disturbance trends were identified. Alpha diversities were determined using Chao1 species estimator, and beta diversity evaluated through the PERMDISP function and main-test Permanova in PERMANOVA+ add-on of Primer-E, to assess species turnovers. Parameters were compared cross-site using general linear models while indicator species were identified using Indval function in R. Significant responses to impacts of anthropogenic disturbance were observed in abundance of birds overall, abundance of upper-stratum species, and in terms of alpha diversity of carnivores but not for other guilds. On the other hand, species turnovers occurred along the disturbance gradient for birds overall, in frugivores and also for both upper- and lower-stratum species. Species functional redundancies, depicting diminished habitat complexities, were detected in the most disturbed site for birds overall, amongst carnivores, all herbivores combined, and among the lower and middle-stratum species, but were not evident for birds overall in the low- or moderately-disturbed sites, nor among upper-stratum bird species. Only two species, both carnivorous, qualified as potential candidates for monitoring disturbance trends across the three woodland sites. These results demonstrate negative effects of anthropogenic disturbance on peri-urban woodland bird assemblage and composition, and greater resilience of taxonomic over functional diversity in response to such disturbance, but also that while formal protection may enhance bird’s community-level functional roles, not all guilds may benefit. Mitigating effects of disturbance requires measures for improving habitat structural heterogeneity to broaden birds’ assemblage composition, diversify their ecosystem roles at all levels and promote their site-based avi-tourism potential.

The Sterile Insect Technique: Success and Perspectives in the Neotropics.

The sterile insect technique (SIT), an environmentally friendly means of control, is currently used against plant, animal, and human pests under the area-wide integrated pest management. It consists in the mass production, sterilization, and release of insects in an affected area where sterile males mate with wild females leading to no reproduction. Here, we review SIT in the Neotropics and focus on particular recent successful cases of eradication of the Mediterranean fruit fly, Ceratitis capitata (Wiedemann), as well as effective programs used against the Mexican fruit fly Anastrepha ludens (Loew), the New World screwworm fly Cochliomyia hominivorax (Coquerel)), and the Cactus moth Cactoblastis cactorum (Berg). We examine when SIT does not work and innovations that have made SIT more efficient and also highlight complimentary techniques that can be used in conjunction. We address potential candidate species that could be controlled through SIT, for example Philornis downsi Dodge & Aitken. Finally, we consider the impact of climate change in the context of the use of the SIT against these pests. Given the recent dramatic decline in insect biodiversity, investing in environmentally friendly means of pest control should be a priority. We conclude that SIT should be promoted in the region, and leadership and political will is needed for continued success of SIT in the Neotropics.

Effect of Fish Silage Supplemented Diets on Growth and Health Status of Pangas Catfish, Pangasianodon hypophthalmus Fry

Background: Freshwater Asian catfish, Pangasianodon hypophthalmus (pangas) is one of the fastest growing exotic species throughout world including India. Most recently, it has been considered as a potential candidate species for carp diversification especially in northern states of India including Punjab and Haryana. In Pangas culture, fish meal is used as primary protein source pertaining to its excellent amino acid profile, palatability and high nutritive value. However, due to continuously rising cost, limited availability and quality variations of fish meal, there is need to find out less expensive alternative quality protein sources. Among these, fish silage is easy to prepare product with high nutritional value and shelf life. In this view, the experimental study was conducted to evaluate the possibility of replacing fish meal with fish silage supplemented diets on growth and health status of Pangas catfish. Methods: Indoor study was conducted in FRP pools (1.5×1×0.75m) for 120 days (July – October 2018) to evaluate the effect of acid fermented fish silage (prepared from fish waste collected from local fish market of Ludhiana, Punjab) for Pangas catfish fry. To study the effect of fish silage, four experimental diets were formulated by replacing fishmeal @ 50% and 100% and mixture of soybean and groundnut meal @ 25% and 50% levels from control diet along with one reference diet without any animal protein source (neither fish meal nor fish silage) Results: The overall results of present study revealed that fish silage can be incorporated (100% replacement of fish meal with fish silage) in the diet of Pangas catfish fry (P. hypophthalmus) with improved growth and feed utilization along with positive influence on health status of fish in terms of general haematology, biochemistry and anti-oxidant status.