Undiscovered Biodiversity Research Articles

A new approach allows morphological recognition of cryptic diversity of the krill genus Hansarsia (formerly Nematoscelis)

Abstract Cryptic and pseudocryptic species are found on all major branches of the tree of life and probably represent a significant portion of undiscovered biodiversity, yet their identification is currently possible solely on the basis of molecular analyses. Here, we tested an alternative approach and hypothesized that all genetic clades might be identified on a morphological basis, and we analysed the morphology of nine previously detected genetic clades of Hansarsia. We made 169 sets of measurements (12 quantitative characters for each), ran multinomial logistic regression models, and showed a high ability of these models to generalize (i.e. to be able to classify correctly new specimens not included in our data matrix). The five to seven most ‘powerful’ characters provided a significant detection rate; these characters were shown to represent distinct evolutionary traits. Our findings cast some doubt on the presence of the ‘merely’ cryptic species; instead, we suggest that any genetic divergence found via traditional genetic markers is also mirrored in morphological divergence and can be detected using a combination of quantitative characters and appropriate mathematical tools. We provide a script key to genetic clades of the Atlantic Hansarsia based solely on morphological measurements and encourage other researchers to use quantitative morphological characters for detection of cryptic clades in other taxa.

Population-level variation in gut bifidobacterial composition and association with geography, age, ethnicity, and staple food

Bifidobacteria are key gut commensals that confer various health benefits and are commonly used as probiotics. However, little is known about the population-level variation in gut bifidobacterial composition and its affecting factors. Therefore, we analyzed Bifidobacterium species with amplicon sequencing of the groEL gene on fecal samples of 1674 healthy individuals, who belonged to eight ethnic groups and resided in 60 counties/cities of 28 provinces across China. We found that the composition of the bifidobacterial community was associated with geographical factors, demographic characteristics, staple food type, and urbanization. First, geography, which reflects a mixed effect of other variables, explained the largest variation in the bifidobacterial profile. Second, middle adolescence (age 14–17) and age 30 were two key change points in the bifidobacterial community development, and a bifidobacterial community resembling that of adults occurred in middle adolescence, which is much later than the maturation of the whole gut microbial community at approximately age 3. Third, each ethnicity showed a distinct bifidobacterial profile, and the remarkable amount of unknown Bifidobacterium species in the Tibetan gut suggested undiscovered biodiversity. Fourth, wheat as the main staple food promoted the flourish of B. adolescentis and B. longum. Fifth, alpha diversity of the bifidobacterial community decreased with urbanization. Collectively, our findings provide insight into the environmental and host factors that shape the human gut bifidobacterial community, which is fundamental for precision probiotics.

Exceptional levels of species discovery ameliorate inferences of the biogeography and diversification of an Afrotropical catfish family

Endeavours in species discovery, particularly the characterisation of cryptic species, have been greatly aided by the application of DNA molecular sequence data to phylogenetic reconstruction and inference of evolutionary and biogeographic processes. However, the extent of cryptic and undescribed diversity remains unclear in tropical freshwaters, where biodiversity is declining at alarming rates. To investigate how data on previously undiscovered biodiversity impacts inferences of biogeography and diversification dynamics, we generated a densely sampled species-level family tree of Afrotropical Mochokidae catfishes (220 valid species) that was ca. 70 % complete. This was achieved through extensive continental sampling specifically targeting the genus Chiloglanis a specialist of the relatively unexplored fast-flowing lotic habitat. Applying multiple species-delimitation methods, we report exceptional levels of species discovery for a vertebrate genus, conservatively delimiting a staggering ca. 50 putative new Chiloglanis species, resulting in a near 80 % increase in species richness for the genus. Biogeographic reconstructions of the family identified the Congo Basin as a critical region in the generation of mochokid diversity, and further revealed complex scenarios for the build-up of continental assemblages of the two most species rich mochokid genera, Synodontis and Chiloglanis. While Syndontis showed most divergence events within freshwater ecoregions consistent with largely in situ diversification, Chiloglanis showed much less aggregation of freshwater ecoregions, suggesting dispersal as a key diversification process in this older group. Despite the significant increase in mochokid diversity identified here, diversification rates were best supported by a constant rate model consistent with patterns in many other tropical continental radiations. While our findings highlight fast-flowing lotic freshwaters as potential hotspots for undescribed and cryptic species diversity, a third of all freshwater fishes are currently threatened with extinction, signifying an urgent need to increase exploration of tropical freshwaters to better characterise and conserve its biodiversity.

Diversity and distribution of Kinorhyncha in abyssal polymetallic nodule areas of the Clarion-Clipperton Fracture Zone and the Peru Basin, East Pacific Ocean, with the description of three new species and notes on their intraspecific variation

Polymetallic nodule fields represent a large reservoir of undiscovered biodiversity that becomes particularly evident for meiobenthic organisms, the smallest-sized faunal group. Knowledge gaps are especially noticeable for the generally low-density metazoan groups, such as Kinorhyncha, the so-called mud dragons. Using both morphological and genetic (metabarcoding) approaches, we provide a general overview and comparison of the diversity of kinorhynchs collected during nine sampling campaigns (2016–2019) that targeted abyssal environments in several contract areas for exploration in the Clarion-Clipperton Fracture Zone (CCZ) and in the Peru Basin. Our findings from morphological analyses reveal a highly diverse mud dragon community, with 16 species present in the CCZ. Of these, 12 appear in the German contract area, including three new species described in the present contribution: Echinoderes delaordeni sp. nov., Echinoderes sanctorum sp. nov., and Echinoderes zeppilliae sp. nov. Furthermore, metabarcoding data of the kinorhynch community gathered from the area is provided, together with the geographic distribution of the known species stated per contractor area, including new records and still undescribed species. Most of the identified species in the CCZ seem to have a wide distribution, with Echinoderes sp.4 being the most common and abundant species with a distribution spreading across the CCZ and also present in the Peru Basin. Metabarcoding analyses targeting the V1V2 hypervariable region of the 18S gene from the 253 stations of the CCZ revealed 14 amplicon sequence variants (ASVs) belonging to Kinorhyncha with grade values higher than 98% detected at 15 different stations within six different areas along the CCZ. Concurring with morphology, the family Echinoderidae was the most diverse as the genus Cephalorhyncha had five ASVs, followed by Echinoderes with four ASVs. Semnoderes, however, showed the widest spread ASV, being detected at six stations. In the CCZ, the metabarcoding data showed there were no shared ASVs between the CCZ areas as well as the highest number of uniques, which was 11. Our morphological study showed a low number of specimens inhabiting nodules (surface/crevices), suggesting that specific kinorhynch species do not typically inhabit the nodules in addition to the surrounding sediment.

First in situ observations of the benthic-demersal fauna on the upper continental slope off Punta Pichalo (19°36'S), northern Chile

An autonomous lander equipped with a video camera (dropcam) was used for in situ observations of the bento-demersal macrofauna on the upper continental slope off Punta Pichalo in northern Chile, an area of permanent coastal upwelling processes, located ~70 km north of Iquique. The lander was deployed at nine stations and between 227 and 798 m of depth. According to morphological characteristics, 34 operational taxonomic units (OTUs) were identified to the lowest taxonomic level; 24 belonged to macroinvertebrates and 10 to fishes. Macroinvertebrates comprised 9 OTUs of crustaceans, seven cnidarians, and six echinoderms. Fishes included 3 OTUs of the order Chondrichthyes, 3 belonging to macrourid. Perciformes, Anguilliformes, and Alepocephaliformes were represented by one OTU each. Also, we observed one species of lanternfish (Myctophidae). Apart from the brachyuran decapod Lophorochinia parabranchia Garth, 1969 and euphausiids, all species were observed at depths greater than 560 m. The presence of one individual identified as the granulate dogfish Centroscyllium granulatum Günther, 1887 extended the known distribution range of this species about 1000 km to the north. Images taken at 795 m showed Bathyraja peruana McEachran & Miyake, 1984. Our study suggests that the upper continental slope of northern Chile harbors nearly undiscovered biodiversity, worth to be studied more intensively to complete the comparable sparse knowledge about marine biodiversity and species distribution at the continental margin in front of Chile.

First record of functional underground traps in a pitcher plant: Nepenthespudica (Nepenthaceae), a new species from North Kalimantan, Borneo.

Nepenthespudica, a new species from North Kalimantan, Indonesia, is described and illustrated. The species belongs to the N.hirsuta group (sensu Cheek and Jebb 1999) but exhibits some characters that are unique within the group or even within the genus. Above all, it produces underground, achlorophyllous shoots with well-developed, ventricose lower pitchers that form in soil cavities or directly in the soil. No lower pitchers are formed above ground. The main part of its prey are ants, besides other litter- and soil-inhabiting species of invertebrates. A number of infaunal species were found in both aerial and underground pitchers, mainly Diptera and nematodes. Nepenthespudica is known only from a few neighbouring localities in the Mentarang Hulu district of North Kalimantan, where it grows on ridgetops at an elevation of 1100-1300 m. Its discovery underlines the natural richness of Borneo's rainforest and the necessity to preserve this important ecosystem with its enormous and still undiscovered biodiversity.

How to Accurately Delineate Morphologically Conserved Taxa and Diagnose Their Phenotypic Disparities: Species Delimitation in Cryptic Rhinolophidae (Chiroptera)

Systematics and taxonomy are the backbone of all components of biology and ecology, yet cryptic species present a major challenge for accurate species identification. This is especially problematic as they represent a substantial portion of undiscovered biodiversity, and have implications for not only species conservation, but even assaying potential risk of zoonotic spillover. Here, we use integrative approaches to delineate potential cryptic species in horseshoe bats (Rhinolophidae), evaluate the phenotypic disparities between cryptic species, and identify key traits for their identification. We tested the use of multispecies coalescent models (MSC) using Bayesian Phylogenetic and Phylogeography (BPP) and found that BPP was useful in delineating potential cryptic species, and consistent with acoustic traits. Our results show that around 40% of Asian rhinolophid species are potentially cryptic and have not been formally described. In order to avoid potential misidentification and allow species to be accurately identified, we identified quantitative noseleaf sella and acoustic characters as the most informative traits in delineating between potential cryptic species in Rhinolophidae. This highlights the physical differences between cryptic species that are apparent in noseleaf traits which often only qualitatively described but rarely measured. Each part of the noseleaf including the sella, lateral lappets, and lancet furrows, play roles in focusing acoustic beams and thus, provide useful characteristics to identify cryptic Rhinolophus species. Finally, species delimitation for cryptic species cannot rely on genetic data alone, but such data should be complemented by other evidence, including phenotypic, acoustic data, and geographic distributions to ensure accurate species identification and delineation.

The Importance of Accurate Host Species Identification in the Framework of Rabies Surveillance, Control and Elimination.

Accurate host identification is paramount to understand disease epidemiology and to apply appropriate control measures. This is especially important for multi-host pathogens such as the rabies virus, a major and almost invariably fatal zoonosis that has mobilized unanimous engagement at an international level towards the final goal of zero human deaths due to canine rabies. Currently, diagnostic laboratories implement a standardized identification using taxonomic keys. However, this method is challenged by high and undiscovered biodiversity, decomposition of carcasses and subjective misevaluation, as has been attested to by findings from a cohort of 242 archived specimens collected across Sub-Saharan Africa and submitted for rabies diagnosis. We applied two simple and cheap methods targeting the Cytochrome b and Cytochrome c oxidase subunit I to confirm the initial classification. We therefore suggest prioritizing a standardized protocol that includes, as a first step, the implementation of taxonomic keys at a family or subfamily level, followed by the molecular characterization of the host species.

Castela senticosa (Simaroubaceae: Sapindales), a New Species from the Caribbean Clade Endemic to Seasonally Dry Tropical Forest on Hispaniola

Abstract— Recent fieldwork in the Sierra Martín García in southwestern Dominican Republic has yielded a new species of the American clade Castela (Simaroubaceae), Castela senticosa sp. nov., from seasonally dry tropical forest. This species has been collected from two separate localities, including Môle St. Nicolas in northwestern Haiti in 1929, but until now fertile material with both flowers and fruit was unknown. We provide a photographic plate and illustration, place it phylogenetically using plastome data, and compare it morphologically with close relatives. This increases the number of known species of Castela on Hispaniola from one to two, both of which are endemic but from different clades, and yields another species for the Greater Antilles, a known biodiversity hotspot and clear center of diversification for this group of arid-adapted, thorny shrubs. This work emphasizes that seasonally dry, tropical forests, although often understudied, house as yet undiscovered biodiversity and deserve far more comprehensive studies.

Expanding known global biodiversity of Yamaguticestus (Cestoda: Phyllobothriidea) parasitizing catsharks (Pentanchidae and Scyliorhinidae)

This paper aimed to test the prediction that substantial undiscovered biodiversity in the tapeworm genus Yamaguticestus Caira, Bueno & Jensen, 2021 exists in the 16 of 18 genera of catsharks globally that have not yet been examined for tapeworms. A total of 200 catsharks of 10 species representing eight genera were sampled opportunistically from the waters off Australia, Chile, Malaysian Borneo, South Africa, South Korea, and the UK between 1991 and 2017. Six species in four genera (i.e., Apristurus Garman, Asymbolus Whitley, Holohalaelurus Fowler, and Scyliorhinus Blainville) were found to host a total of six new species of Yamaguticestus, tripling the number of described species. The new species are Yamaguticestus africanae sp. nov. from Scyliorhinus capensis, Yamaguticestus ellisi sp. nov. from Scyliorhinus canicula, Scyliorhinus fairweatherae sp. nov. from Holohalaelurus regani, Yamaguticestus kihongkimi sp. nov. from Scyliorhinus torazame, and Yamaguticestus kuchtai sp. nov. from Apristurus aphyodes. The new species were characterized using a combination of light and scanning electron microscopy; sequence data for the D1–D3 region of the 28S rRNA gene were generated for five of the species. Transfer of a species formerly assigned to Calyptrobothrium Monticelli, 1893 that is morphologically consistent with Yamaguticestus added Cephaloscyllium Gill to the list of catshark genera known to host this genus. Most tapeworm species exhibited a remarkably low prevalence and intensity of infection suggesting that our failure to detect infection in the four genera of sharks represented by small sample sizes may not be indicative of their unsuitability as hosts. Our results suggest that the earlier prediction that 70 species of Yamaguticestus remain to be discovered in catsharks across the planet may actually be an underestimate. http://zoobank.org/urn:lsid:zoobank.org:pub:63F48CF6-ED06-44FC-839D-

Hadal Mud Dragons: First Insight Into the Diversity of Kinorhyncha From the Atacama Trench

Deep-sea trenches are one of the last frontiers for deep-sea exploration and represent a large reservoir of undiscovered biodiversity. This applies in particular to organisms belonging to smaller-size classes, such as meiofauna. Among different meiofauna taxa, kinorhynchs represent a large gap in our knowledge about global marine biodiversity in general, but primarily in extreme deep-sea environments. Out of the more than 300 known mud dragon species, only a single species has ever been described from hadal depths (> 6000 m), i.e., Echinoderes ultraabyssalis from the Kuril-Kamchatka Trench. The results presented in this paper are based on material collected during a research expedition in 2018 investigating the Atacama Trench environment. We provide a first overview and comparison of the diversity and abundance of mud dragons in the Atacama Trench, the adjacent abyssal plain and continental slope off Chile. The study revealed six species of Echinoderes. Of these, Echinoderes mamaqucha sp. nov. is described as a new species and morphological data of three undescribed species are given. Because of the low number of available specimens, we provide only a brief description of these three species and comparison with their morphologically closest congeners, but formal descriptions are not given. Moreover, Echinoderes juliae and Echinoderes pterus were also recovered. Echinoderes juliae was described from the abyssal plain off Oregon and along the continental rise off California, at 2702 to 3679 m depth. Echinoderes pterus is known from the high Arctic, the North Atlantic, and the Mediterranean Sea, and has also been reported to show a wide bathymetric distribution, from 675 to 4403 m. Interestingly, E. mamaqucha sp. nov. dominated at the trench stations and it reached its highest abundance at the deepest station, at 8085 m water depth. The only other single individual that was found in the Atacama Trench was Echinoderes sp.1. The remaining four species were all found at the abyssal and slope stations. The obtained results seem to confirm previous hypotheses about geographic isolation of deep-sea trenches and relatively low connectivity with other habitats, reflected by limited diversity of sediment dwelling fauna, particularly in the deepest parts of trenches.

A new species of Chromis damselfish from the tropical western Atlantic (Teleostei, Pomacentridae).

Initially described in 1882, Chromisenchrysurus, the Yellowtail Reeffish, was redescribed in 1982 to account for an observed color morph that possesses a white tail instead of a yellow one, but morphological and geographic boundaries between the two color morphs were not well understood. Taking advantage of newly collected material from submersible studies of deep reefs and photographs from rebreather dives, this study sought to determine whether the white-tailed Chromis is actually a color morph of Chromisenchrysurus or a distinct species. Phylogenetic analyses of mitochondrial genes cytochrome b and cytochrome c oxidase subunit I separated Chromisenchrysurus and the white-tailed Chromis into two reciprocally monophyletic clades. A principal component analysis based on 27 morphological characters separated the two groups into clusters that correspond with caudal-fin coloration, which was either known or presumed based on the specimen’s collection site according to biogeographic data on species boundaries in the Greater Caribbean. Genetic, morphological, and biogeographic data all indicate that the white-tailed Chromis is a distinct species, herein described as Chromisvanbebberaesp. nov. The discovery of a new species within a conspicuous group such as damselfishes in a well-studied region of the world highlights the importance of deep-reef exploration in documenting undiscovered biodiversity.

Dark, rare and inspirational microbial matter in the extremobiosphere: 16 000 m of bioprospecting campaigns.

The rationale of our bioprospecting campaigns is that the extremobiosphere, particularly the deep sea and hyper-arid deserts, harbours undiscovered biodiversity that is likely to express novel chemistry and biocatalysts thereby providing opportunities for therapeutic drug and industrial process development. We have focused on actinobacteria because of their frequent role as keystone species in soil ecosystems and their unrivalled track record as a source of bioactive compounds. Population numbers and diversity of actinobacteria in the extremobiosphere are traditionally considered to be low, although they often comprise the dominant bacterial biota. Recent metagenomic evaluation of 'the uncultured microbial majority' has now revealed enormous taxonomic diversity among 'dark' and 'rare' actinobacteria in samples as diverse as sediments from the depths of the Mariana Trench and soils from the heights of the Central Andes. The application of innovative culture and screening options that emphasize rigorous dereplication at each stage of the analysis, and strain prioritization to identify 'gifted' organisms, have been deployed to detect and characterize bioactive hit compounds and sought-after catalysts from this hitherto untapped resource. The rewards include first-in-a-class chemical entities with novel modes of action, as well as a growing microbial seed bank that represents a potentially enormous source of biotechnological and therapeutic innovation.

DNA barcoding of the funoran-producing red algal genus Gloiopeltis (Gigartinales) and description of a new species, Gloiopeltis frutex sp. nov.

The funoran-producing red macroalga, Gloiopeltis, is known for its commercial uses. Since the economic value of Gloiopeltis is species-dependent, accurate species identification using molecular analysis such as DNA barcoding is important to obtain species-level identification and reveals the hitherto undiscovered biodiversity in Gloiopeltis. In this study, we investigated Gloiopeltis complanata specimens from various locations across Japan and Korea to confirm their relationships with specimens from the type locality in Japan. We employed a combination of molecular analyses using mitochondrial COI-5P as DNA barcoding and plastid rbcL markers, as well as detailed morphological examination of reproductive structures. Genetic analysis revealed the presence of two deeply divergent clades with nucleotide difference of 16.8–17.5% in COI-5P and 6.3–6.8% in rbcL, respectively. The difference in the position of reproductive structure in thallus further supported the subdivision of the Japanese and Korean specimens. As a result, we describe a new species, Gloiopeltis frutex sp. nov., based on the Korean specimens characterized by caespitose and subcylindrical to compressed thallus, slightly flexuous siphonous axis, cruciately divided tetrasporangia scattered over thallus, and slightly swollen cystocarps on proliferations. The results also suggest the necessity of further studies aimed at examining full spectrum of genetic diversity manifested in species of the family Endocladiaceae in detail.

Lunachloris lukesovae gen. et sp. nov. (Trebouxiophyceae, Chlorophyta), a novel coccoid green alga isolated from soil in South Bohemia, Czech Republic

Culture collections of microorganisms can still hold undiscovered biodiversity; with molecular techniques, considerable progress has been made in characterizing microalgae which were isolated in the past and misidentified due to a lack of morphological features. However, many strains are still awaiting taxonomic reassessment. Here we analysed the phylogenetic position, morphology and ultrastructure of the strain CCALA 307 previously identified as Coccomyxa cf. gloeobotrydiformis Reysigl isolated in 1987 from field soil in South Bohemia, Czech Republic. Molecular phylogenetic analyses based on SSU rDNA and the plastid rbcL gene revealed that the strain CCALA 307 formed a distinct sister lineage to Neocystis and Prasiola clades within the Trebouxiophyceae. We describe this strain as a new genus and species, Lunachloris lukesovae. Multiple conserved nucleotide positions identified in the secondary structures of the highly variable ITS2 rDNA barcoding marker provide further evidence of the phylogenetic position of Lunachloris. Minute vegetative cells of this newly recognized species are spherical or ellipsoid, with a single parietal chloroplast without a pyrenoid. Asexually, it reproduces by the formation of 2–6 autospores. Since the majority of recent attention has been paid to algae from the tropics or extreme habitats, the biodiversity of terrestrial microalgae in temperate regions is still notably unexplored and even a ‘common’ habitat like agricultural soil can contain new, as yet unknown species. Moreover, this study emphasizes the importance of culture collections of microorganisms even in the era of culture-independent biodiversity research, because they may harbour novel and undescribed organisms as well as preserving strains for future studies.

Diversity of Zoantharia (Anthozoa: Hexacorallia) at Dongsha Atoll in the South China Sea

Dongsha Atoll is the largest coral atoll in the South China Sea (SCS), and is expected to harbor high levels of biodiversity as the SCS is located adjacent to the recognized center of maximum marine biodiversity in the central Indo-Pacific (CIP). However, due to its relative isolation, the biodiversity of Dongsha Atoll has not yet been well investigated for most marine taxa. In this study, we report on findings from our survey in 2016 that focused on the order Zoantharia, for which only sporadic previous reports exist from the SCS. Our results indicate some species such as Palythoa tuberculosa are very common around Dongsha Atoll, as well as the presence of at least three undescribed species, including one species only found thus far at the atoll. Overall, we recorded 16 species of Zoantharia from Dongsha Atoll, bringing the total number of zoantharian species in the SCS to 22, close to numbers reported from the CIP (=24 spp.) and southern Japan (=28 spp.). These findings demonstrate the importance of protecting the biodiversity of Dongsha Atoll, and also, given the limited survey coverage, the potential for undiscovered biodiversity in the SCS.

Diversity of deep-sea fishes of the Easter Island Ecoregion

The Easter Island Ecoregion is in the center of the South Pacific gyre and experiences ultra-oligotrophic conditions that could make it highly susceptible to global change and anthropogenic activities, so it is imperative that these regions are characterized and studied so that conservation and sustainable management strategies can be developed. From the few studies from the region, we know that the coastal areas are relatively depauperate and have relatively high rates of endemism. Here, we present a brief report from the first video observations from this region of the deep-dwelling fishes from ROV exploration of benthic communities from 157 to 281m and baited drop-camera videos from 150 to 1850m. We observed a total of 55 fish species from the ROV and Drop-Cam surveys; nine could not be assigned family level or lower, 26 were observed in the ROV surveys, 29 were observed in the Drop-Cam surveys, nine were observed with both survey methods, at least six species are potentially new to science, and nine species were observed at deeper depths than previously reported. These new reports may be indicative of the unique oceanographic conditions in the area and the relative isolation of the communities that have provided opportunity for the evolution of new species and favorable conditions for range expansion. In contrast, these new reports may be indicative of the severe undersampling in the south Pacific at mesopelagic depths. The prevalence of potentially new species suggests that the region likely harbors a wealth of undiscovered biodiversity.

Trouble at the top? Restricted distribution and extreme population isolation in an alpine crustacean assemblage with unexpected lineage diversity

Summary The fragile alpine freshwater ecosystems of Australia are threatened by historic land use and projected climate change, yet little is known about the fauna of these environments. The aim of this study was to analyse the phylogeography of two important components of this ecosystem, an amphipod (Neoniphargus) and an isopod (Coluboltelson), to determine the potential impacts of environmental change on these crustaceans. DNA sequences were generated for the mitochondrial cytochrome c oxidase subunit I (COI) and nuclear 28S ribosomal RNA (28S) of 229 amphipods and 153 isopods from 19 sites across seven creeks in the Bogong High Plains, Victoria, Australia. Phylogenetic analyses were undertaken to define evolutionary significant units (ESUs), and population genetic structure was examined. Analyses of both markers found deep divergences in both taxa, leading to the definition of six amphipod and two isopod ESUs, within both Neoniphargus and Colubotelson. The majority of amphipod ESUs exhibited highly restricted distributions, with essentially no gene flow between sites, even within the same creeks, consistent with the Death Valley Model of population connectivity. By contrast, both isopod ESUs had overlapping distributions across the entire sample area and exhibited some highly limited population connectivity among sites in adjacent headwaters, consistent with the Headwater Model. This study suggests that there is a high level of undiscovered biodiversity within Australian alpine aquatic invertebrates. The highly limited population structure, and restricted distributions have important consequences for the conservation of the headwaters of Australia's largest river system. These findings indicate that habitat loss and/or fragmentation associated with environmental change will result in biodiversity reductions, with species unlikely to shift their ranges in response to future climate change, or recover rapidly from localised extinction events.

Discovery Strategies of Bioactive Compounds Synthesized by Nonribosomal Peptide Synthetases and Type-I Polyketide Synthases Derived from Marine Microbiomes.

Considering that 70% of our planet’s surface is covered by oceans, it is likely that undiscovered biodiversity is still enormous. A large portion of marine biodiversity consists of microbiomes. They are very attractive targets of bioprospecting because they are able to produce a vast repertoire of secondary metabolites in order to adapt in diverse environments. In many cases secondary metabolites of pharmaceutical and biotechnological interest such as nonribosomal peptides (NRPs) and polyketides (PKs) are synthesized by multimodular enzymes named nonribosomal peptide synthetases (NRPSes) and type-I polyketide synthases (PKSes-I), respectively. Novel findings regarding the mechanisms underlying NRPS and PKS evolution demonstrate how microorganisms could leverage their metabolic potential. Moreover, these findings could facilitate synthetic biology approaches leading to novel bioactive compounds. Ongoing advances in bioinformatics and next-generation sequencing (NGS) technologies are driving the discovery of NRPs and PKs derived from marine microbiomes mainly through two strategies: genome-mining and metagenomics. Microbial genomes are now sequenced at an unprecedented rate and this vast quantity of biological information can be analyzed through genome mining in order to identify gene clusters encoding NRPSes and PKSes of interest. On the other hand, metagenomics is a fast-growing research field which directly studies microbial genomes and their products present in marine environments using culture-independent approaches. The aim of this review is to examine recent developments regarding discovery strategies of bioactive compounds synthesized by NRPS and type-I PKS derived from marine microbiomes and to highlight the vast diversity of NRPSes and PKSes present in marine environments by giving examples of recently discovered bioactive compounds.

Twenty-Eight New Records of Lichenized Fungi from Nepal: A Signature of Undiscovered Biodiversity in Central Himalaya

Twenty-eight new records of lichenized fungi have been reported from the community forest of Dadeldhura situated in Mahakali zone of far west Nepal. The species diversity is distributed in 13 families (Acarosporaceae, Arthoniaceae, Caliciaceae, Chrysothrichaceae, Cladoniaceae, Collemataceae, Graphidaceae, Lecanoraceae, Parmeliaceae, Physciaceae, Pyrenulaceae, Ramalinaceae, Verrucariaceae), showing 4 growth forms (squamulose, crustose, foliose and dimorphic) reported from three (soil, bark and rocks) substrata. A brief annotated morpho-taxonomic description of all the 28 species along with their ecology and distribution is given. Photomicrographs of all the described species are provided for visual validation. Taxonomic, growth form and substratum diversity of all 28 described species is discussed. A supplementary conspectus table is provided, giving overview of the phorophyte diversity of corticolous species along with the taxonomy and growth form diversity of described lichen species. The findings have been discussed in light of less explored region in central Himalaya and importance of community forests in Nepal for diversity studies.