A5083926119- Parasite Biology and Host Interactions
- Helminth infection and control
- Amphibian and Reptile Biology
- Parasites and Host Interactions
- Bird parasitology and diseases
- Evolution and Genetic Dynamics
- Animal Behavior and Reproduction
- Genetic diversity and population structure
- Study of Mite Species
- Plant and animal studies
- Primate Behavior and Ecology
- Dermatological diseases and infestations
- Leech Biology and Applications
- Genomics and Phylogenetic Studies
- Myxozoan Parasites in Aquatic Species
- Aquatic Invertebrate Ecology and Behavior
- Species Distribution and Climate Change
- Insect and Arachnid Ecology and Behavior
- Animal Ecology and Behavior Studies
- Wildlife Ecology and Conservation
- Evolution and Paleontology Studies
- Turtle Biology and Conservation
- Vector-borne infectious diseases
- Insect symbiosis and bacterial influences
- Physiological and biochemical adaptations
University of Bristol
2008-2021
Czech Academy of Sciences, Biology Centre
2017
Flinders University
2006
Queen Mary University of London
1981-1994
Universidad de Londres
1994
University College London
1978-1992
University of London
1979-1992
University of West London
1981
University of Geneva
1977
Keele University
1973-1975
African clawed frogs, genus Xenopus, are extraordinary among vertebrates in the diversity of their polyploid species and high number independent polyploidization events that occurred during diversification. Here we update current understanding evolutionary history this group describe six new from west central sub-Saharan Africa, including four tetraploids two dodecaploids. We provide information on molecular variation, morphology, karyotypes, vocalizations, estimated geographic ranges, which...
Protopolystoma xenopodis (Price, 1943) Bychowsky, 1957 is a parasite of the African clawed toads, species Xenopus . Adult worms in host's urinary bladder produce up to 15 eggs/24 h; these are voided with urine and hatch after 20–24 days (at 26 °C). The swimming oncomiracidia enter cloaca toad travel via ducts kidneys. Larval development kidneys lasts 8–12 weeks 22 °C) juvenile parasites then migrate where maturity reached further 3–4 weeks, i.e months invasion. Egg production continuous...
A method is presented for the isolation and analysis of hamuli, marginal hooks, bars from individual gyrodactylid monogeneans using scanning electron microscopy (SEM), while simultaneously processing parasites rDNA polymerase chain reaction (PCR). The haptors ethanol-fixed gyrodactylids were protease digested to liberate hooks SEM, whereas DNA extracted bodies was used PCR. resulted in hamuli being prepared more than 90% Gyrodactylus turnbulli individuals, a significant improvement on...
Invasive, non-native species represent a major threat to biodiversity worldwide. The African amphibian Xenopus laevis is widely regarded as an invasive and local faunas. Populations originating at the Western Cape, South Africa, have been introduced on four continents, mostly in areas with similar Mediterranean climate. Some populations are also established cooler environments where persistence for many decades suggests capacity long-term adaptation. In these cases, recent climate warming...
Transmission by Gyrodactylus turnbulli occurs most frequently when its hosts (Poecilia reticulata) come into close contact. This study is the first description of a specific migratory behavior that facilitates transmission gyrodactylid from dead hosts. Recently-dead guppies typically float at water's surface; G. moves off these fish water film, hanging motionless with haptor held surface tension. Because are feeders, detached parasites in film more likely to contact new host.
The Ethiopian highlands - home to striking species diversity and endemism are bisected by the Rift Valley, a zone of tectonic divergence. Using molecular data we examined evolutionary history two co-distributed African clawed frog (Xenopus clivii X. largeni) that endemic this region. Our field collections substantially extend known distribution largeni, formerly from southeast Rift, but also occurs northwest. In both species, analysis mitochondrial DNA 19 autosomal loci identifies...
Abstract Parasite-mediated models of sexual selection predict that females should avoid parasitized mates, thereby generating on male traits revealing health. The strength this selection, however, may depend the prevalence parasitism among if their infection status alters mate preferences. We evaluated effects a socially transmitted parasite and female behaviour in spadefoot toads. Parasitized males were larger better condition than unparasitized males. Moreover, produced longer calls....
SUMMARY Some unique features of monogenean biology have emerged from studies on 2 polystomatids which infect spadefoot toads in Arizona, USA: Pseudodiplorchis americanus Scaphiopus couchii and Neodiplorchis scaphiopodis S. multiplicatus bombifrons . Transmission is confined to 1–3 nights each summer when the desert-adapted enter water spawn. Encapsulated larvae complete development utero hatch within seconds deposition; their body length (up 600 μm) 2–4 times greater than that most other...
A comprehensive, accurate, and revisable alpha taxonomy is crucial for biodiversity studies, but challenging when data from reference specimens are difficult to collect or observe. However, recent technological advances can overcome some of these challenges. To illustrate this, we used modern approaches tackle a centuries-old taxonomic enigma presented by Fraser's Clawed Frog, Xenopus fraseri, including whether X. fraseri different other species, if so, where it situated geographically...
Egg production by the freshwater gill monogenean Discocotyle sagittata infecting rainbow trout ( Oncorhynchus mykiss ) was monitored at 5, 13 and 18°C; eggs were incubated 6, 10, 13, 15, 16, 18, 22 26°C hatching times determined. Mean per capita output 13°C ranged from 0·8 eggs/worm/day (e/w/d) to 18·3 e/w/d for 25 hosts (burdens 1–17 worms/host). Average egg rates worms in single burdens varied 3 e/d 14·6 13°C, mean 7·6 (±0·63) n =8). temperature dependent, increasing a of 1·5 5°C 12·0...
The survival characteristics of Discocotyle sagittata larvae are both age- and temperature-dependent. In laboratory studies at constant temperatures 6, 10, 13, 18 22°C, oncomiracidia had a maximum life-span 96 h 6°C, declining with increasing temperature to 26 22°C. Larval swimming activity was also age dependent, continued for large proportion time. relationship between time which stop as total statistically significant temperatures. Proportionally, swam longer periods lower As age, they...
Despite the importance of reproduction in platyhelminth parasite biology, there is generally only sketchy information on key parameters; many studies lack documentation variation and limited application laboratory to natural events. This review focuses case involving monogeneans (species genera Polystoma, Protopolystoma, Pseudodiplorchis, Discocotyle, Gyrodactylus) where experimental data are linked with fieldwork produce exact measurements life-history traits. Data characterized by wide...
A new species of clawed toad, Xenopus wittei sp. nov. is described from highland areas overlapping the borders Rwanda, Uganda and Zaire. comprehensive morphological analysis has been carried out. X. very closely related to vestitus both have a tetraploid chromosome complement (2 n = 72), only examples within genus. Nevertheless, two may be distinguished by easily observed features, including head morphology dorsal body colours patterns, are also identified their karyotypes mating calls. Data...
A new species of African clawed toad, Xenopus kigesiensis sp.n., has been recorded from Lake Mutanda in South‐west Kigezi, Uganda. Information on the biology and morphological variation compiled a sample preserved field collection living specimens maintained laboratory. An analysis characters conducted its relationships with six known genus assessed. In early part this century toad populations occupying lakes South‐West Kigezi exclusively comprised laevis subspecies. It appears that X. sp.n....