ABSTRACT
The African savanna elephant (Loxodonta africana) is the largest terrestrial animal on Earth and is found primarily in Southern and Eastern Africa. It is a hindgut, colonic fermenter and subsists on a diet of raw plant materials found in its grazing area. In this study the bacterial, archaeal and fungal populations of seven African savanna elephant fecal metagenomes were first characterized using amplicon sequencing. On the genus level it was observed that the p-1088-a5 gut group in the bacteriome, Methanocorpusulum and Methanobrevibacter in the archaeome and Alternaria, Aurobasidium, Didymella and Preussia in the mycome, predominated. Subsequently, metagenomic shotgun sequencing was employed to identify possible functional pathways and carbohydrate-active enzymes (CAZymes). Carbohydrate catabolic pathways represented the main degradation pathways, and the fecal metagenome was enriched in the glycohydroside (GH) class of CAZymes. Additionally, the top GH families identified - GH43, GH2, GH13 and GH3 - are known to be associated with cellulytic, hemicellulytic and pectolytic activities. Finally, the CAZymes families identified in the African savanna elephant were compared with those found in the Asian elephant and it was demonstrated that there is a unique repository of CAZymes that could be leveraged in the biotechnological context such as the degradation of lignocellulose for the production of second-generation biofuels and energy.
Subject(s)
Bacteria , Elephants , Feces , Gastrointestinal Microbiome , Metagenome , Animals , Elephants/genetics , Elephants/microbiology , Feces/microbiology , Bacteria/genetics , Bacteria/classification , Bacteria/isolation & purification , Archaea/genetics , Archaea/classification , Metagenomics , Fungi/genetics , Fungi/classificationABSTRACT
Little is known about microplastics (MPs) in adult frogs. We investigated MPs in adult Common River Frogs (Amietia delalandii) from Potchefstroom, South Africa. Five kinds of samples were analysed: natural water, water used to rinse the skin, skin, intestine, and the remainder of the body (corpus). Tissues were digested. Microplastics occurred in all frogs and sample types (1128 MPs counted). Fibres were the most prevalent MP. Fibre lengths were between 28 and 4300 µm, either polyester or polyvinyl alcohol. MPs in skin were likely derived from the ambient, and MPs in the corpus from translocation via the skin. Fibres in tissues were significantly shorter in larger frogs, a phenomenon we provisionally assign to in situ biodegradation. Microplastics in frogs can potentially be transferred through the food web to higher trophic levels. This study provides the first evidence of MPs in adult frog tissues and avenues for further investigations.
Subject(s)
Microplastics , Water Pollutants, Chemical , Animals , Plastics , Water Pollutants, Chemical/analysis , Rivers , Anura , Water , Environmental MonitoringABSTRACT
The COVID-19 pandemic has highlighted our reliance on biocides, the increasing prevalence of resistance to biocides is a risk to public health. Bacterial exposure to the biocide, benzalkonium chloride (BAC), resulted in a unique transcriptomic profile, characterised by both a short and long-term response. Differential gene expression was observed in four main areas: motility, membrane composition, proteostasis, and the stress response. A metabolism shift to protect the proteome and the stress response were prioritised suggesting these are main resistance mechanisms. Whereas "well-established" mechanisms, such as biofilm formation, were not found to be differentially expressed after exposure to BAC.
ABSTRACT
Previous literature suggests that Indigenous cultural practices, specifically traditional medicine, are commonplace among urban communities contrary to the general conception that such practices are restricted to rural societies. We reviewed previous literature for records of herptiles (frog and reptile species) sold by traditional health practitioners in urban South Africa, then used visual confirmation surveys, DNA barcoding and folk taxonomy to identify the herptile species that were on sale. Additionally, we interviewed 11 IsiZulu and SePedi speaking traditional health practitioners to document details of the collection and pricing of herptile specimens along with the practitioners' views of current conservation measures for traditional medicine markets. The 34 herptile species recorded in previous literature on traditional medicine markets included endangered and non-native species. Spectrophotometry measurements of the DNA we extracted from the tissue of herptiles used in traditional medicine were an unreliable predictor of whether those extractions would be suitable for further experimental work. From our initial set of 111 tissue samples, 81 sequencing reactions were successful and 55 of those sequences had species-level matches to COI reference sequences on the NCBI GenBank and/or BOLD databases. Molecular identification revealed that traditional health practitioners correctly labelled 77% of the samples that we successfully identified with DNA barcoding in this study. Our mixed methodology approach is useful for conservation planning as it updates knowledge of animal use in Indigenous remedies and can accurately identify species of high conservation priority. Furthermore, this study highlights the possibility of collaborative conservation planning with traditional health practitioners.
ABSTRACT
Nematodes of the genus Cosmocerca are commonly found in various amphibians in South Africa and in most cases are identified as C. ornata. However, after detailed morphological studies and molecular approaches, three new species of the genus were recently described from three different frogs in South Africa. In present study, we describe another new species - Cosmocerca goroensis parasitising the Northern Pygmy Toad Poyntonophrynus fenoulheti in Soutpansberg mountains, Limpopo province, South Africa. The new species is characterised by prominent sex dimorphism, wide lateral alae, numerous somatic papillae in both sexes, and wide triangularly shaped gubernaculum and simple prominent spicules in males. Cosmocerca goroensis n. sp. distinguished from congeners, previously reported in Southern Africa by the shape of the gubernaculum and arrangement of somatic papillae in males. Morphological differences were confirmed by molecular analysis based on fragments of the 28S gene. Phylogenetic analysis based on the 28S gene fragments, including C. goroensis n. sp. and newly obtained sequence of C. ornata from Pelophylax lessonae from Ukraine, supported previously known data of closer relationships between species of Cosmocerca and Aplectana and more distant with Cosmocercoides spp.
Subject(s)
Ascaridida , Nematoda , Male , Female , Animals , Phylogeny , South Africa , Species Specificity , Anura , Bufonidae , Ascaridida/anatomy & histologyABSTRACT
Trachemys dorbigni is the most abundant freshwater turtle species in Rio Grande do Sul, southern Brazil. Chelonians are known to host a wide variety of pathogens, including viruses, bacteria, hemoparasites and helminths. Among these, nine genera of polystomatid flatworms (Monogenoidea; Polystomatidae) infect freshwater turtles: Apaloneotrema, Aussietrema, Fornixtrema, Manotrema, Pleurodirotrema, Polystomoidella, Polystomoides, Uropolystomoides and Uteropolystomoides. However, little is known about the biology of these parasites in the Neotropical Realm. Through investigative cystoscopy, specimens of Polystomatidae were located inside the urinary bladder of the host T. dorbigni. Retrieved specimens were fixed and stained whole mounts prepared for taxonomic identification. In the present paper, a new species of Polystomoides (Monogenoidea: Polystomatidae) parasitizing the urinary bladder of a freshwater turtle of the species T. dorbigni in Brazil is described. Polystomoides santamariensis n. sp. differs from the congeneric species on the length of the genital spines, which are longer. Given the enormous diversity of freshwater turtles around the world, it is likely that a large number of chelonian polystomatids are still unknown.
Subject(s)
Trematoda , Turtles , Animals , Turtles/parasitology , Urinary Bladder , Brazil , Fresh Water/parasitologyABSTRACT
While monogenean worms are mainly parasites of the gills and skin of fish, and to a lesser extent parasites of the oral cavity, urinary bladder, and/or conjunctival sacs of amphibians and freshwater turtles, Oculotrema hippopotamiStunkard, 1924 is the single monogenean polystome reported from a mammal, the common hippopotamus (Hippopotamus amphibius Linnaeus). Several hypotheses have been suggested in the last decade to explain the origin of this enigmatic parasite which infects the conjunctival sacs of H. amphibius. Based on a molecular phylogeny inferred from nuclear (28S and 18S) and mitochondrial (12S and COI) sequences of O. hippopotami and chelonian polystomes, we found a sister group relationship between O. hippopotami and Apaloneotrema moleri (Du Preez & Morrison, 2012). This result suggests lateral parasite transfer between freshwater turtles and hippopotamuses, thus likely reflecting one of the most exceptional known examples of host-switching in the course of vertebrate evolution. It also demonstrates that the proximity in the ecological habitat of parasites within host species is an important feature for their speciation and diversification. Because A. moleri and its host, the Florida softshell turtle (Apalone ferox (Schneider)), are restricted to the USA, we suggest that an ancestral stock of parasites may have been isolated on primitive African trionychids after they diverged from their American relatives, and then switched to hippopotamuses or anthracotheres in Africa.
Subject(s)
Artiodactyla , Parasites , Platyhelminths , Trematoda , Turtles , Animals , Platyhelminths/genetics , Phylogeny , Turtles/parasitology , Trematoda/genetics , Artiodactyla/parasitology , MammalsABSTRACT
PURPOSE: Despite Madagascar's high amphibian diversity of more than 400 species, only a few polystome species are known from the island. The dissection of frogs from museum collections, together with amphibian and parasite surveys conducted in Madagascar led to the discovery of an undescribed polystome infecting Aglyptodactylus madagascariensis. The purpose of this study is to formally describe this species. METHODS: Polystomes recovered from A. madagascariensis were stained (Acetocarmine) and mounted (Canada balsam) to facilitate morphometrics and taxonomic drawings. Some specimens were fixed in absolute alcohol, a Bayesian tree inferred from the analysis of concatenated 18S, 28S and COI gene sequences was constructed and pairwise distances were calculated. Parasites collected from archived hosts in museums were used for histology and scanning electron microscopy (SEM). RESULTS: Polystomes recovered from A. madagascariensis display characteristics of the genus Metapolystoma and morphologically differed from all other known metapolystomes. The Bayesian phylogeny shows that Metapolystoma n. sp. ex. A. madagascariensis and M. falcatum are sister species with high Bayesian posterior probability. Histological and SEM investigations contributed to morphological descriptions. CONCLUSIONS: Morphological examination supported by phylogenetic analysis and genetic divergences revealed distinct differences from all known metapolystome species, supporting the description of a new species. Differences between the life cycles of Metapolystoma and Polystoma provided additional evidence for the validity of that genus as taxon. Whereas Polystoma may display ovoviviparity on rare occasions after incomplete egg expulsion towards the end of the breeding season, Metapolystoma displays true ovoviviparity. We emphasize the need for parasite surveys in Madagascar and recommended for museum material to be examined for polystomes to provide supplementary material and localities for further field investigation.
Subject(s)
Parasites , Trematoda , Animals , Anura/parasitology , Phylogeny , Bayes TheoremABSTRACT
The aquatic and terrestrial clades of species of Trypanosoma could provide insight into the evolutionary history of the genus, as well as complementary information for biomedical studies of medically and economically important species of Trypanosoma. The ecological interactions and phylogeny of aquatic trypanosomes are currently not well-understood, mostly due to their complex life cycles and a deficiency of data. The species of Trypanosoma from African anuran hosts are of the least understood taxa in the genus. Trypanosomes were collected from South African frogs and subjected to morphological and phylogenetic analyses. This study redescribes Trypanosoma (Trypanosoma) nelspruitense Laveran, 1904 and Trypanosoma (Haematomonas) grandicolor Pienaar, 1962, with morphological and molecular data. The present study aims to create a platform for further future research on African anuran trypanosomes.
Subject(s)
Trypanosoma , Animals , Phylogeny , Trypanosoma/genetics , AnuraABSTRACT
Hormesis, or the hormetic effect, is a dose- or concentration-dependent response characterised by growth stimulation at low concentrations and inhibition at high concentrations. The impact of sub-lethal levels of disinfectants on the growth of Serratia species is critical to understanding the increasing number of outbreaks caused by this pathogen in healthcare settings. Serratia sp. HRI and Serratia marcescens ATCC 13880 were cultivated in sub-lethal levels of benzalkonium chloride (BAC), Didecyldimethylammonium chloride (DDAC), and VirukillTM. The maximum specific growth rates, doubling times, and cell counts were compared. The results revealed significant increases in maximum specific growth rates and shorter doubling times for Serratia sp. HRI when cultivated in sub-lethal levels of BAC and DDAC. The significant stimulatory effect of sub-lethal levels of these disinfectants for Serratia sp. HRI represents the first time hormesis has been observed in a Gram-negative bacterium for any disinfectant. Furthermore, this study is the first to observe the hormetic effect after treatment with DDAC and the second study to date analysing the impact of sub-lethal levels of disinfectants on the growth of bacterial species.
ABSTRACT
Patterns of the rockcod Notothenia coriiceps infection with helminths were analysed to understand the dynamics of parasite communities in this Antarctic fish and to test their stability over time. The study was performed using helminth samples collected from 183 N. coriiceps in 2014-2015 and 2020-2021 in the vicinity of the Ukrainian Antarctic station (UAS) "Akademik Vernadsky", Galindez Island, Argentine Islands, West Antarctica. Overall, 25 helminth taxonomical categories (nine trematodes, four cestodes, five nematodes, and seven acanthocephalans) were subjected to analysis. A direct comparison of the helminth population characteristics showed that nine species significantly changed their infection parameters during the 6 years between the samples. Seven of them (Pseudoterranova sp., Contracaecum sp., Ascarophis nototheniae, monolocular metacestodes, bilocular metacestodes, Metacanthocephalus rennicki, and Diphyllobothrium sp.) were found to have a significant impact on the differences between helminth infracommunities in 2014-2015 and 2020-2021. Most studied patterns of helminth component community appeared to show a stable tendency, and observed fluctuations were close to the steady trend. Slight but significant changes in the infection patterns observed in this study might have been caused by changes in the populations of intermediate, paratenic, and definitive hosts of helminths (marine invertebrates, mammals, and birds), which participate in helminth transmission in Antarctic ecosystems.
Subject(s)
Helminthiasis, Animal , Helminths , Perciformes , Animals , Antarctic Regions , Ecosystem , Perciformes/parasitology , Fishes , Mammals , Helminthiasis, Animal/epidemiology , Helminthiasis, Animal/parasitologyABSTRACT
INTRODUCTION: Species of Fimbriaria are common tapeworms of ducks (Anseriformes). In this study, cestode specimens identified as F. fasciolaris, F. czaplinskii and F. teresae from the Helminthological Collection of IZSHK are re-examined and newly collected cestodes of the genus Fimbriaria from various anseriform birds in Ukraine are examined. METHODS: Cestode specimens were studied using light microscopy. For two of these species, Fimbriaria fasciolaris and Fimbriaria teresae, partial sequences of the genes 18S, 28S, COX1 and NAD were obtained. Also, archived specimens from Ukrainian and Poland were also studied and partly re-identified. RESULTS: The revision of all collected cestodes identified as Fimbriaria spp. revealed that species of the genus differ by the morphology of the copulative apparatus. Based on the analysis of our data and literature sources, a key to Fimbriaria species is provided.
Subject(s)
Anseriformes , Cestoda , Cestode Infections , Animals , Ukraine , Cestode Infections/veterinary , Cestoda/anatomy & histology , BirdsABSTRACT
Polystomatid flatworms of amphibians are represented in the Neotropical realm by species of Mesopolystoma, Nanopolystoma, Parapseudopolystoma, Polystoma, Riojatrema and Wetapolystoma but only species of Polystoma are known from Brazil, namely Polystoma cuvieri, P. knoffi, P. lopezromani and P. travassosi. During a survey of monogeneans infecting amphibians in the north-eastern region of Pará State, the Cayenne Caecilian Typhlonectes compressicauda was found to be infected with Nanopolystoma tinsleyi and the Veined Tree Frog Trachycephalus typhonius was found to harbor Polystoma lopezromani. A yet unknown species of Polystoma was also encountered in the urinary bladder of the Steindachner's Dwarf Frog, Physalaemus ephippifer. This new species, which is the second species reported from Physalaemus spp., is described herein as Polystoma goeldii n. sp. and its life cycle is also illustrated. The new species can be distinguished from Polystoma spp. from other neotropical realm by a combination of characteristics, including hamuli morphology, outer/inner hamuli length ratio, haptor/total body length ratio, genital bulb/total body length ratio, genital spine number and COI molecular characters.
Subject(s)
Parasites , Platyhelminths , Trematoda , Animals , Anura/parasitology , Urinary Bladder/parasitology , Trematoda/genetics , Trematoda/anatomy & histology , Platyhelminths/genetics , Platyhelminths/anatomy & histologyABSTRACT
Polystomatids are platyhelminth parasites that infect mainly amphibians and freshwater turtles. For more than seven decades, chelonian polystomes were classified into three genera according to the number of hamuli, i.e. absent for Neopolystoma, one pair for Polystomoidella and two pairs for Polystomoides. Following re-examination of morphological characters, seven new genera were erected the past six years, namely Apaloneotrema, Aussietrema, Fornixtrema, Manotrema, Pleurodirotrema, Uropolystomoides and Uteropolystomoides. However, the polyphyly of Neopolystoma and Polystomoides on the one hand, and the nested position of Uteropolystomoides within a clade encompassing all Neopolystoma and Polystomoides spp. on the other, still raised questions about the validity of these genera. We therefore re-examined several types, paratypes and voucher specimens, and investigated the molecular phylogeny of polystomes sampled from the oral cavity of North American turtles to re-evaluate their systematic status. We show that all Polystomoides Ward, 1917, sensu Du Preez et al., 2022, Neopolystoma Price, 1939, sensu Du Preez et al., 2022 and Uteropolystomoides Tinsley, 2017 species, display vaginae that are peripheral and extend well beyond the intestine. We thus reassign all species of the clade to Polystomoides and propose nine new combinations; however, although Uteropolystomoides is nested within this clade, based on its unique morphological features, we propose to keep it as a valid taxon. Polystomoides as redefined herein groups all polystome species infecting either the oral cavity or the urinary bladder of cryptodires, with peripheral vaginae and with or without two pairs of small hamuli. Uteropolystomoides nelsoni (Du Preez & Van Rooyen 2015), originally described from Pseudemys nelsoni Carr is now regarded as Uteropolystomoides multifalx (Stunkard, 1924) n. comb. infecting three distinct Pseudemys species of North America.
Title: Révision de la systématique des Polystomoidinae (Plathelminthes, Monogenea, Polystomatidae) avec redéfinition des genres Polystomoides Ward, 1917 et Uteropolystomoides Tinsley, 2017. Abstract: Les Polystomatidés sont des plathelminthes parasites qui infestent principalement les amphibiens et les tortues d'eau douce. Pendant plus de sept décennies, les polystomes de chéloniens ont été classés en trois genres selon le nombre d'hamuli, absents pour Neopolystoma, une paire pour Polystomoidella et deux paires pour Polystomoides. Suite au réexamen des caractères morphologiques, sept nouveaux genres ont été érigés ces six dernières années, à savoir Apaloneotrema, Aussietrema, Fornixtrema, Manotrema, Pleurodirotrema, Uropolystomoides et Uteropolystomoides. Cependant, la polyphylie de Neopolystoma et Polystomoides d'une part, et la position imbriquée d'Uteropolystomoides au sein d'un clade englobant toutes les espèces de Neopolystoma et Polystomoides d'autre part, soulèvent encore des questions sur la validité de ces trois genres. Nous avons donc réexaminé plusieurs types, paratypes et vouchers et étudié la phylogénie moléculaire de polystomes prélevés dans la cavité buccale de tortues d'Amérique du Nord pour réévaluer leur statut systématique. Nous montrons que toutes les espèces de Polystomoides Ward, 1917, sensu Du Preez et al., 2022, Neopolystoma Price, 1939, sensu Du Preez et al., 2022 et Uteropolystomoides Tinsley, 2017, présentent des vagins périphériques qui s'étendent bien au-delà de l'intestin. Nous réattribuons ainsi toutes les espèces du clade à Polystomoides et proposons neuf nouvelles combinaisons; cependant, nous proposons de conserver Uteropolystomoides sur la base de ses caractéristiques morphologiques exceptionnelles, bien que son espèce soit imbriquée au sein de ce clade. Polystomoides tel que redéfini ici regroupe toutes les espèces de polystomes infectant soit la cavité buccale, soit la vessie des cryptodires, avec des vagins périphériques, et deux paires de petits hamuli ou sans hamuli. Uteropolystomoides nelsoni (Du Preez & Van Rooyen 2015), l'unique espèce décrite à l'origine à partir de Pseudemys nelsoni Carr est maintenant considérée comme Uteropolystomoides multifalx (Stunkard, 1924) n. comb., qui infecte trois espèces distinctes de Pseudemys d'Amérique du Nord.
Subject(s)
Parasites , Platyhelminths , Trematoda , Turtles , Animals , Platyhelminths/genetics , Phylogeny , Urinary Bladder/parasitology , Turtles/parasitologyABSTRACT
Polystomatids are platyhelminth parasites that infect mostly amphibian and chelonian hosts. Polystomatid of testudines were, for more than seven decades, classified in the three genera - Neopolystoma Price, 1939, Polystomoides Ward, 1917 and Polystomoidella Price, 1939. The genus delimitation was primarily based on the absence of hamuli in Neopolystoma, the presence of one pair of hamuli in Polystomoidella, and two pairs in Polystomoides. From 2016 to 2020, five new genera were erected - namely Uropolystomoides Tinsley and Tinsley, 2016, Uteropolystomoides Tinsley, 2017, Apaloneotrema Du Preez and Verneau, 2020, Aussietrema Du Preez and Verneau, 2020 and Fornixtrema Du Preez and Verneau, 2020. The generic diagnosis was based not only on the size and shape of morphological characters such as hamulus 1, uterus and eggs, but also on the site of infestation (i.e. urinary bladder, oral cavity or conjunctival sacs). Despite large advancements in polystome classification over the last decade, Neopolystoma was still polyphyletic with some species nested within Polystomoides and others being closely related to the Australian Aussietrema. Regarding the distribution of freshwater turtles of the two suborders Pleurodira (Southern continents) and Cryptodira (distributed worldwide except in Australia), one may wonder whether Australian chelonian polystomes of the genus Neopolystoma may have diverged from species infecting other pleurodires of South America. In the present study based on the analysis of several species selected among all genera, we reveal striking morphological differences within polystomes infecting pleurodiran turtles, which herein led to the proposal of two new chelonian polystome genera, Pleurodirotrema n. g. and Manotrema n. g. Pleurodirotrema n. g. is characterized by the absence of hamuli, presence of latero-ventral vaginae and includes species that infect either the oral region or the urinary bladder of Australian hosts of the Pleurodira. Manotrema n. g. is characterized by the presence of small hamuli, latero-ventral vaginae, deep incisions between suckers, a low genital spine number (<10) and includes species that infect the oral region of South American Pleurodira.
ABSTRACT
Three new species of lung-dwelling nematodes are described from the frogs Ptychadena anchietae (Bocage), P. oxyrhynchus (Smith), and P. uzungwensis (Loveridge) in southern Africa. All three species are medium-sized species of Rhabdias Stiles et Hassall, 1905, with the thick-walled buccal capsules measuring 11-13 µm × 6-11 µm, consisting of longer anterior and shorter posterior parts. Rhabdias athos n. sp. and R. porthos n. sp. are characterised by the rounded anterior end of the body and the presence of short dilatation of the oesophagus at its mid-length. Rhabdias porthos n. sp. has distinct excretory glands which are absent in two other species. Rhabdias aramis n. sp. is characterised by the truncated anterior end and the slight constriction of the oesophagus at the level of its mid-length. Phylogenetic analysis based on ITS-28S rDNA sequences placed R. aramis n. sp. in the clade consisting of R. engelbrechti Kuzmin et al., 2017 from South Africa and Eurasian Rhabdias spp., while R. athos n. sp. and R. porthos n. sp. formed a sister group to that clade. Identification key to 14 Rhabdias spp. parasitic in anuran amphibians from the Afrotropical Realm is provided.
Subject(s)
Nematoda , Rhabdiasoidea , Animals , Anura/parasitology , Lung/parasitology , Nematoda/genetics , PhylogenyABSTRACT
Phenotypic variations between populations often correlate with climatic variables. Determining the presence of phenotypic plasticity and local adaptation of a species to different environments over a large spatial scale can provide insight on the persistence of a species across its range. Amphibians, and in particular their larvae, are good models for studies of phenotypic variation as they are especially sensitive to their immediate environment. Few studies have attempted to determine the mechanisms that drive phenotypic variation between populations of a single amphibian species over a large spatial scale especially across contrasting climatic regimes. The African clawed frog, Xenopus laevis, occurs in two regions with contrasting rainfall regimes in southern Africa. We hypothesised that the phenotypic variation of life-history traits of X. laevis tadpoles emerges from a combination of plastic and genetic responses. We predicted that plasticity would allow the development of tadpoles from both regions in each environment. We also predicted that local adaptation of larval traits would drive the differentiation of reaction norms between populations and lower survival in tadpoles reared away from their home environment. We measured growth, time to metamorphosis, and survival in a reciprocal transplant experiment using outdoor mesocosms. Supporting our prediction, we found that the measured variation of all traits was explained by both adaptation and plasticity. However, the reaction norms differed between populations suggesting adaptive and asymmetric plasticity. All tadpoles experienced lower survival when translocated, but only translocated tadpoles from the winter rainfall region matched survival of local tadpoles. This has implications for the dynamics of translocated X. laevis into novel environments, especially from the winter rainfall region. Our discovery of their asymmetric capacity to overcome novel environmental conditions by phenotypic plasticity alone provides insight into their invasion success.
Subject(s)
Adaptation, Physiological , Biological Variation, Population , Animals , Larva , Plastics , Xenopus laevisABSTRACT
This survey analysed the helminth communities associated with three Ukrainian heron species (Ardea cinerea, Ardea purpurea, Nycticorax nycticorax) collected throughout 1947-2019. The sample analysed included 128 specimens, and 55 helminth species were identified. Of these, the most diverse taxonomic group was trematodes with 29 species, followed by cestodes with 14 species, nematodes with nine, and acanthocephalans with three species. The helminth infracommunities were found to be similar across all three host species. Furthermore, the distance to the coastal regions impacts both diversity and species richness in infracommunities.
Subject(s)
Bird Diseases/epidemiology , Birds , Helminthiasis, Animal/epidemiology , Helminths/isolation & purification , Animals , Bird Diseases/parasitology , Helminthiasis, Animal/parasitology , Host Specificity , Prevalence , Species Specificity , Ukraine/epidemiologyABSTRACT
Serpentirhabdias mamlambo n. sp. is described from the lung of the herald snake, Crotaphopeltis hotamboeia (Laurenti) in KwaZulu-Natal Province, South Africa. The new species is characterised by the small lips, the absence of the buccal capsule, the large excretory glands (1.5-2.3 times longer than the oesophagus), and the numerous eggs in uteri. Serpentirhabdias mamlambo n. sp. differs from other Serpentirhabdias spp. in the presence of M-shaped cuticular folds on dorsal and ventral sides of apical surface, the eye-shaped internal labial papillae, and the distinct dilatation of the oesophagus at its mid-length. Morphological differentiation of S. mamlambo n. sp. from its congeners is supported by molecular evidence based on cox1 mitochondrial gene, and ITS and partial 28S region of nuclear rDNA. Serpentirhabdias mamlambo n. sp. is the first species of the genus Serpentirhabdias described from the Afrotropical Realm.
Subject(s)
Rhabditoidea/classification , Snakes/parasitology , Animals , DNA, Ribosomal/genetics , Rhabditoidea/anatomy & histology , Rhabditoidea/genetics , South Africa , Species SpecificityABSTRACT
Although Madagascar has more than 350 frog species of which all but two are endemic to the island, the known polystome (Monogenea: Polystomatidae) diversity parasitizing Malagasy frogs is low, encompassing five species of Madapolystoma, one species of Kankana and one Metapolystoma. Investigating the parasite diversity of frog parasites at selected Malagasy localities led to the discovery of undescribed polystomes. Five treefrogs, Boophis albilabris, Boophis doulioti, Boophis luteus, Boophis madagascariensis and Boophis occidentalis were found to be infected and are reported here as hosts for new Metapolystoma species. Morphological investigation, combining examination of body length, haptor length, genital bulb width, genital crown diameter, genital spine number, genital spine length, ovary length, egg length, hamulus length, hamulus guard length and hamulus hook length, revealed five distinct morphotypes. Phylogenetic analysis and genetic divergences obtained for three of the five morphotypes, support the distinction of new species. Metapolystoma ansuanum n. sp. is described from B. luteus, Metapolystoma falcatum n. sp. from B. doulioti, Metapolystoma multiova n. sp. from B. occidentalis, Metapolystoma theroni n. sp. from B. madagascareniensis and Metapolystoma vencesi n. sp. from B. albilabris. Finally, although the validity of Metapolystoma as taxon is not fully resolved yet, the phylogenetic position of the described species and their morphology provide clear evidence for new metapolystome taxa.