Polystoma australis (Monogenea): Development and reproduction in neotenic parasites

Development and reproduction of neotenic Polystoma australis were investigated in natural anuran Kassina and Semnodactylus hosts in South Africa. Newly established parasites attached mainly inside the left branchial chamber. They then migrated so that parasites older than eight days occurred almost exclusively in the right branchial chamber. Mortality was high and continuous. In young worms age could be readily determined from haptoral structure. At 23°C the developing reproductive system was discernible at seven days. Egg production started at 16 days and could be maintained at constant rates of around 10-20 eggs/ parasite/day for up to 40 days. No crowding effect influencing parasite development or reproduction could be established. These developmental standards could be used to measure the success of parasites subjected to experimental conditions

Multiple emergences of genetically diverse amphibian-infecting chytrids include a globalized hypervirulent recombinant lineage

Batrachochytriumdendrobatidis (Bd) is a globally ubiquitous fungal infection that has emerged to become a primary driver of amphibian biodiversity loss. Despite widespread effort to understand the emergence of this panzootic, the origins of the infection, its patterns of global spread, and principle mode of evolution remain largely unknown. Using comparative population genomics, we discovered three deeply diverged lineages of Bd associated with amphibians. Two of these lineages were found in multiple continents and are associated with known introductions by the amphibian trade.We found that isolates belonging to one clade, the global panzootic lineage (BdGPL) have emerged across at least five continents during the 20th century and are associated with the onset of epizootics in North America, Central America, the Caribbean, Australia, and Europe. The two newly identified divergent lineages, Cape lineage (BdCAPE) and Swiss lineage (BdCH), were found to differ in morphological traits when compared against one another and BdGPL, and we show that BdGPL is hypervirulent. BdGPL uniquely bears the hallmarks of genomic recombination, manifested as extensive intergenomic phylogenetic conflict and patchily distributed heterozygosity. Wepostulate that contact between previously genetically isolated allopatric populations of Bd may have allowed recombination to occur, resulting in the generation, spread, and invasion of the hypervirulent BdGPL leading to contemporary disease-driven losses in amphibian biodiversity.Peer Reviewe

Mom’s taxi – Maternal care in shovel-nosed frogs Hemisus marmoratus and Hemisus guttatus

This communication details the maternal care of Hemisus marmoratus and Hemisus guttatus. A Hemisus mother stays with the eggs, protecting them during their time in the nest chamber, and ensures their ultimate arrival in a body of water, at varying stages of development, via a variety of different techniques, ranging from nest placement and slide construction to tadpole transportation. We confirm that a sticky glue-like substance is used during inguinal amplexus of H. guttatus, with only the hands of the male being glued to the female. Field observations indicate that H. marmoratus females carry their offspring to the water, gluing her hind legs together to increase the surface area for the tadpoles to adhere to during the journey. Keywords: amplexus, eggs, glue-like substance, nest placement, parental care, reproduction, tadpole

Polystomoides bourgati (Monogenea: Polystomatidae) infecting Pelusios castaneus in southern Nigeria

Pelusios spp. procured from four locations in southern Nigeria were investigated for polystomatid infection. None of the P. niger examined haboured monogeneans. Pelusios castaneus from Sapele, Ossisa and Abeokuta were infected with P. bourgati in the urinary bladder. The morphometrics of the parasites from the infected Nigerian terrapins were in the same range as those previously described from Togo and Senegal, except that the Senegalese specimens were slightly smaller with respect to the body size. While the testes of the specimens recovered from Ossisa and Abeokuta were ovoid to round in shape, those in parasites recovered from turtles purchased from Sapele were lobed and laterally elongated. Two of the parasite specimens recovered from turtles purchased in Ossisa had seven haptoral suckers. This is the first report of such an occurrence among polystomes.Key words: Pelusios castaneus, P. niger, Polystomoides bourgati, Nigeria

Polystoma nacialtuneli n. sp. (Monogenea: Polystomatidae) from the eastern spadefoot, Pelobates syriacus (Pelobatidae) in Turkey

Polystoma nacialtuneli n. sp. is described from the urinary bladder of the eastern spadefoot, Pelobates syriacus from Turkey. This is the fifth polystome species known from Turkey and the third species in Pelobates. We show that this new parasite species can be distinguished from other polystome species in the area by a combination of characteristics, including parasite size and the shape and size of the hamuli. Polystoma pelobatis from Pelobates cultripes has a pair of well-developed hamuli, while P. fuscus from Pe. fuscus characteristically has a pair of underdeveloped hamuli barely larger than the marginal hooklets. Polystoma nacialtuneli n. sp. has well-developed hamuli that vary significantly in shape. Phylogenetic relationships of P. nacialtuneli n. sp. within Polystoma, supplemented with molecular divergences estimated from internal transcribed spacer 1 (ITS1) sequences, indicate that they are well separated from their closest relatives, i.e. P. fuscus and P. pelobatis from Pe. fuscus and Pe. cultripes, respectively.http://dx.doi.org/10.1017/S0022149X1100010

Freshwater mollusc diversity in the Kruger National Park: a comparison between a period of prolonged drought and a period of exceptionally high rainfall

Most of the previous records of the freshwater molluscs from the Kruger National Park date back to 1966 and earlier. On account of several droughts between 1966 and 1995, a survey was done in 1995 to evaluate the effect of these droughts on the mollusc population. As a result of extensive rainfall between 1995 and 2000 another survey was conducted to establish the effect of a period of exceptionally high rainfall on the species’ diversity of the mollusc population. With the exception of three habitats, an increase in mollusc diversity was recorded for all the other habitats previously surveyed. One of the invader freshwater snail species, Aplexa marmorata, collected in only one habitat in 1995, was found in seven habitats located mainly in the south during the 2001 survey. Another interesting finding was that juvenile specimens of Lanistes ovum, of which large specimens were present prior to 1966 but none found in 1995, were present in the Sirheni Dam in 2001. From this study the positive effect of the high rainfall on the species’ diversity is highly evident

Tracking platyhelminth parasite diversity from freshwater turtles in French Guiana: First report of Neopolystoma Price, 1939 (Monogenea: Polystomatidae) with the description of three new species.

International audienceBackgroundPolystomatid flatworms in chelonians are divided into three genera, i.e. Polystomoides Ward, 1917, Polystomoidella Price, 1939 and Neopolystoma Price, 1939, according to the number of haptoral hooks. Among the about 55 polystome species that are known to date from the 327 modern living chelonians, only four species of Polystomoides are currently recognised within the 45 South American freshwater turtles.MethodsDuring 2012, several sites in the vicinity of the cities Cayenne and Kaw in French Guiana were investigated for freshwater turtles. Turtles were collected at six sites and the presence of polystomatid flatworms was assessed from the presence of polystome eggs released by infected specimens.ResultsAmong the three turtle species that were collected, no polystomes were found in the gibba turtle Mesoclemmys gibba (Schweigger, 1812). The spot-legged turtle Rhinoclemmys punctularia (Daudin, 1801) was infected with two species of Neopolystoma Price, 1939, one in the conjunctival sacs and the other in the urinary bladder, while the scorpion mud turtle Kinosternon scorpioides (Linnaeus, 1766) was found to be infected with a single Neopolystoma species in the conjunctival sacs. These parasites could be distinguished from known species of Neopolystoma by a combination of morphological characteristics including body size, number and length of genital spines, shape and size of the testis. They were also differentiated at the molecular level using the cox1 gene marker. Based on morphological and genetic evidences, three new species are described herein, namely Neopolystoma cayensis n. sp. and Neopolystoma guianensis n. sp. from the bladder and the conjunctival sacs of R. punctularia, respectively, and Neopolystoma scorpioides n. sp. from the conjunctival sacs of K. scorpioides. However the monophyly of Polystomoides and Neopolystoma is still questioned regarding their phylogeny based on a dataset comprising four concatenated genes, namely, 18S, 28S and 12S rRNA genes and cox1.ConclusionsIn addition to these being the first chelonian polystomes to be reported and described from French Guiana, they represent the first polystomes from the hosts K. scorpioides and R. punctularia and the first representatives of Neopolystoma from South America. Chelonian polystomes now require an in-depth morphological study to reconcile the taxonomy of the genera with species evolution

Repeated reduction in parasite diversity in invasive populations of Xenopus leavis: a global experiment in enemy release

The introduction of species to multiple continents creates natural experiments suited to the evaluation of ecological hypotheses. For the Enemy Release Hypothesis (ERH), which postulates that the success of invasive populations hinges upon release from the effects of their natural enemies, assessments of parasite loss during invasion across independent geographical replicates are scarce. This study is the first to test the ERH for a globally invasive amphibian, Xenopus laevis, a successful invader on four continents with a well-described parasite fauna. In this study, the metazoan parasite communities of X. laevis from 20 invasive and 27 native sites in five countries and three continents were compared. An overall pattern of reduced parasite diversity in invasive X. laevis was not yet countered by acquisition of novel parasites. Invasive X. laevis harboured impoverished parasite communities that were distinct from those of native X. laevis from undisturbed habitats. Conversely, parasite communities from native X. laevis from disturbed habitats were similar to those from the invasive range. Accompanying parasites were common in the native range and included both generalists with indirect and specialists with direct life cycles. Our findings emphasise that parasite loss is characteristic of the invasion process of X. laevis and possibly contributes to its success as a global invader. The ERH is supported in terms of metazoan parasites as natural enemies, irrespective of the geographical origin, climatic conditions and invasion history of the host populations. This study also draws attention to parasites that co-invade with their hosts as invaders in their own right

Etologie studie op die Gewone Rivier padda ( <i>Amietia angolensis<i/> ) met hulp van moderne tegnologiese mikrotransponders

<div style="font-size: 12px; font-family: serif; left: 227.349px; top: 341.607px; transform: scale(1.11694, 1); transform-origin: 0% 0% 0px;" dir="ltr">In die botaniese tuin van die Noordwes Universiteit is 18 damme en poele wat wissel van klein</div><div style="font-size: 12px; font-family: serif; left: 227.349px; top: 357.607px; transform: scale(1.13754, 1); transform-origin: 0% 0% 0px;" dir="ltr">oranamentele poele tot groot damme. Hierdie damme bied huisvesting aan ‘n groot populasie</div><div style="font-size: 12px; font-family: serif; left: 227.349px; top: 373.607px; transform: scale(1.11851, 1); transform-origin: 0% 0% 0px;" dir="ltr">Gewone Rivierpaddas (Amietia angolensis). Dit het die geleentheid gebied om ‘n gedragstudie</div><div style="font-size: 12px; font-family: serif; left: 227.349px; top: 389.607px; transform: scale(1.1161, 1); transform-origin: 0% 0% 0px;" dir="ltr">op die paddas te doen. Alhoewel die rivierpadda baie algemeen in Suidelike Afrika voorkom is</div><div style="font-size: 12px; font-family: serif; left: 227.349px; top: 405.607px; transform: scale(1.1118, 1); transform-origin: 0% 0% 0px;" dir="ltr">besonder min oor sy gedrag bekend.</div