Cross‐continental comparison of parasite communities in a wide‐ranging carnivore suggests associations with prey diversity and host density

Three species of parasitoids viz., Telenomus dignus Gahan, Trichogramma japonicum, Ishii and Tetrastichus schoenobii Ferriere were recorded from the egg masses of rice yellow stem borer, Scirpophaga incertulas (Walker) in a field study. The extent of parasitism was high during Rabi (43.33 – 93.33 %) and low during Kharif (0 - 40.00 %). Parasitism by T. dignus was maximum in October (50.00 %), T. japonicum, in November (23.08 %) and T. schoenobii in February (55.55 %). dignus and T. schoenobii in combination parasitized maximum number of egg masses (41.82 %). Multiple parasitism by the three species was high in December (8.33 %) and January (7.14%). Parasitic potential was maximum, when T. schoenobii alone parasitised the egg masses followed by T. dignus and T. schoenobii in combination. Host density in the field influenced the extent of parasitism.

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Metazoan Parasites and Health State of European Eel, Anguilla Anguilla (Anguilliformes, Anguillidae), From Tonga Lake and El Mellah Lagoon in the Northeast of Algeria

Vestnik Zoologii ◽

10.2478/vzoo-2018-0029 ◽

2018 ◽

Vol 52 (4) ◽

pp. 279-288 ◽

Cited By ~ 1

Author(s):

F. Bakaria ◽

S. Belhaoues ◽

N. Djebbari ◽

M. Tahri ◽

I. Ladjama ◽

...

Keyword(s):

Brackish Water ◽

Parasite Species ◽

Anguilla Anguilla ◽

European Eel ◽

Health State ◽

Component Community ◽

Metazoan Parasites ◽

Parasite Communities ◽

High Dominance ◽

Argulus Foliaceus

Abstract The aim of the study was to examine metazoans parasite communities of European eels (Anguilla anguilla) in freshwater (Tonga Lake) and brackish water (El Mellah lagoon) in the northeast of Algeria. Six parasite taxa were collected: one monogenean, Pseudodactylogyrus sp.; two crustaceans, Ergasilus sp. and Argulus foliaceus; two nematodes, Cucullanus sp. and Anguillicola crassus; one cestode, Bothriocephalus claviceps. Th e most prevalent parasite taxa in freshwater were Pseudodactylogyrus sp., A. crassus and Bothriocephalus claviceps; whereas in the brackish water, eels were infected mainly with A. crassus. Th e characteristics of the parasite component community structure revealed low parasite species diversity and high dominance values in eels from the two localities. Both communities were dominated by a single parasite species: Tonga eels by the monogenean Pseudodactylogyrus sp. and El Mellah lagoon eels by the nematode A. crassus, verified by high Berger-Parker dominance values of 0.76 and 0.87 respectively.

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Quantifying 25 years of disease‐caused declines in Tasmanian devil populations: host density drives spatial pathogen spread

Ecology Letters ◽

10.1111/ele.13703 ◽

2021 ◽

Vol 24 (5) ◽

pp. 958-969

Author(s):

Calum X. Cunningham ◽

Sebastien Comte ◽

Hamish McCallum ◽

David G. Hamilton ◽

Rodrigo Hamede ◽

...

Keyword(s):

Host Density ◽

Tasmanian Devil

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Feeding diverse prey as an excellent strategy of mixotrophic dinoflagellates for global dominance

Science Advances ◽

10.1126/sciadv.abe4214 ◽

2021 ◽

Vol 7 (2) ◽

pp. eabe4214

Author(s):

Hae Jin Jeong ◽

Hee Chang Kang ◽

An Suk Lim ◽

Se Hyeon Jang ◽

Kitack Lee ◽

...

Keyword(s):

Genetic Factor ◽

Red Tide ◽

Biogeochemical Cycles ◽

Evolutionary Strategy ◽

Distribution Data ◽

Red Tides ◽

Trade Off ◽

Moderate Growth ◽

Prey Diversity ◽

Standing Question

Microalgae fuel food webs and biogeochemical cycles of key elements in the ocean. What determines microalgal dominance in the ocean is a long-standing question. Red tide distribution data (spanning 1990 to 2019) show that mixotrophic dinoflagellates, capable of photosynthesis and predation together, were responsible for ~40% of the species forming red tides globally. Counterintuitively, the species with low or moderate growth rates but diverse prey including diatoms caused red tides globally. The ability of these dinoflagellates to trade off growth for prey diversity is another genetic factor critical to formation of red tides across diverse ocean conditions. This finding has profound implications for explaining the global dominance of particular microalgae, their key eco-evolutionary strategy, and prediction of harmful red tide outbreaks.

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Host density predicts the probability of parasitism by avian brood parasites

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2018.0204 ◽

2019 ◽

Vol 374 (1769) ◽

pp. 20180204 ◽

Cited By ~ 3

Author(s):

Iliana Medina ◽

Naomi E. Langmore

Keyword(s):

Spatial Distribution ◽

Reproductive Success ◽

Host Species ◽

Field Data ◽

Host Density ◽

Brood Parasites ◽

Parasitism Rates ◽

Analyse Data ◽

First Time ◽

Determining Factor

The spatial distribution of hosts can be a determining factor in the reproductive success of parasites. Highly aggregated hosts may offer more opportunities for reproduction but can have better defences than isolated hosts. Here we connect macro- and micro-evolutionary processes to understand the link between host density and parasitism, using avian brood parasites as a model system. We analyse data across more than 200 host species using phylogenetic comparative analyses and quantify parasitism rate and host reproductive success in relation to spatial distribution using field data collected on one host species over 6 years. Our comparative analysis reveals that hosts occurring at intermediate densities are more likely to be parasitized than colonial or widely dispersed hosts. Correspondingly, our intraspecific field data show that individuals living at moderate densities experience higher parasitism rates than individuals at either low or high densities. Moreover, we show for the first time that the effect of host density on host reproductive success varies according to the intensity of parasitism; hosts have greater reproductive success when living at high densities if parasitism rates are high, but fare better at low densities when parasitism rates are low. We provide the first evidence of the trade-off between host density and parasitism at both macro- and micro-evolutionary scales in brood parasites. This article is part of the theme issue ‘The coevolutionary biology of brood parasitism: from mechanism to pattern’.

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High parasite diversity in a neglected host: larval trematodes of Bithynia tentaculata in Central Europe

Journal of Helminthology ◽

10.1017/s0022149x19001093 ◽

2020 ◽

Vol 94 ◽

Author(s):

J. Schwelm ◽

O. Kudlai ◽

N.J. Smit ◽

C. Selbach ◽

B. Sures

Keyword(s):

Central Europe ◽

Phylogenetic Analyses ◽

Snail Host ◽

Morphological Data ◽

Curonian Lagoon ◽

Parasite Communities ◽

Bithynia Tentaculata ◽

Host Parasite ◽

Host Families ◽

High Parasite

Abstract Bithynids snails are a widespread group of molluscs in European freshwater systems. However, not much information is available on trematode communities from molluscs of this family. Here, we investigate the trematode diversity of Bithynia tentaculata, based on molecular and morphological data. A total of 682 snails from the rivers Lippe and Rhine in North Rhine-Westphalia, Germany, and 121 B. tentaculata from Curonian Lagoon, Lithuania were screened for infections with digeneans. In total, B. tentaculata showed a trematode prevalence of 12.9% and 14%, respectively. The phylogenetic analyses based on 55 novel sequences for 36 isolates demonstrated a high diversity of digeneans. Analyses of the molecular and morphological data revealed a species-rich trematode fauna, comprising 20 species, belonging to ten families. Interestingly, the larval trematode community of B. tentaculata shows little overlap with the well-studied trematode fauna of lymnaeids and planorbids, and some of the detected species (Echinochasmus beleocephalus and E. coaxatus) constitute first records for B. tentaculata in Central Europe. Our study revealed an abundant, diverse and distinct trematode fauna in B. tentaculata, which highlights the need for further research on this so far understudied host–parasite system. Therefore, we might currently be underestimating the ecological roles of several parasite communities of non-pulmonate snail host families in European fresh waters.

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Applying predator-prey theory to modelling immune-mediated, within-host interspecific parasite interactions

Parasitology ◽

10.1017/s0031182009991788 ◽

2010 ◽

Vol 137 (6) ◽

pp. 1027-1038 ◽

Cited By ~ 41

Author(s):

ANDY FENTON ◽

SARAH E. PERKINS

Keyword(s):

Functional Response ◽

Interspecific Interactions ◽

Parasite Load ◽

Multiple Infections ◽

Functional Responses ◽

Predator Prey ◽

Immune Activity ◽

Parasite Communities ◽

Immune Mediated ◽

Predator Prey Models

SUMMARYPredator-prey models are often applied to the interactions between host immunity and parasite growth. A key component of these models is the immune system's functional response, the relationship between immune activity and parasite load. Typically, models assume a simple, linear functional response. However, based on the mechanistic interactions between parasites and immunity we argue that alternative forms are more likely, resulting in very different predictions, ranging from parasite exclusion to chronic infection. By extending this framework to consider multiple infections we show that combinations of parasites eliciting different functional responses greatly affect community stability. Indeed, some parasites may stabilize other species that would be unstable if infecting alone. Therefore hosts' immune systems may have adapted to tolerate certain parasites, rather than clear them and risk erratic parasite dynamics. We urge for more detailed empirical information relating immune activity to parasite load to enable better predictions of the dynamic consequences of immune-mediated interspecific interactions within parasite communities.

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BIOLOGY OF TACHINAEPHAGUS ZEALANDICUS (HYMENOPTERA: ENCYRTIDAE), PARASITOID OF SYNANTHROPIC DIPTERA

The Canadian Entomologist ◽

10.4039/ent106785-8 ◽

1974 ◽

Vol 106 (8) ◽

pp. 785-800 ◽

Cited By ~ 23

Author(s):

G. S. Olton ◽

E. F. Legner

Keyword(s):

Life History ◽

Developmental Stages ◽

Average Length ◽

Host Density ◽

Adult Emergence ◽

Reproductive Period ◽

Laboratory Studies ◽

Pupal Parasitoid ◽

History Of ◽

Parasitoid Development

AbstractThe synonymy, distribution, host range, and life history of the gregarious larval–pupal parasitoid Tachinaephagus zealandicus Ashmead, is discussed. Laboratory studies of its biology were conducted at 25° ± 2 °C using Musca domestica L. as host. Its developmental stages are described. Under laboratory conditions its life cycle lasted 23–27 days. Parasitoid development accelerated with higher average densities per host. Single standardized hosts produced 3–18 adult parasitoids. Mated females provided with hosts lived 50.4–67.2 h. The average length of the reproductive period and number of hosts parasitized were independent of host density; however, the average number of eggs deposited per host increased at lower host densities. Adult emergence displayed circadian rhythmicity independent of photoperiod over 3+ days.

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Helminth Parasite Communities of the Water-rat, Hydromys chrysogaster, from Queensland

Wildlife Research ◽

10.1071/wr96074 ◽

1997 ◽

Vol 24 (4) ◽

pp. 445 ◽

Cited By ~ 11

Author(s):

L. R. Smales ◽

T. H. Cribb

Keyword(s):

Bimodal Distribution ◽

Helminth Fauna ◽

Helminth Community ◽

Parasite Communities ◽

Far North ◽

Core Species ◽

Helminth Communities ◽

Eastern Australia ◽

Hydromys Chrysogaster ◽

High Diversity

The helminth fauna from 124 water-rats, Hydromys chrysogaster, collected from 33 localities in Queensland was analysed. A total of 45 species of helminths was found, comprising 2 acanthocephalans, 2 cestodes, 13 nematodes and 28 trematodes. The helminth community of the water-rats in the region north of latitude 18˚ (far north) was different from that of water-rats south of 18˚ (central); Sorensen’s Index 45·8% similarity, whereas Holmes and Podesta’s Index gave 32·1% similarity. Comparisons with data from water-rats from southern and Tasmanian regions showed that they were different from each other and from both Queensland regions. The helminth communities were characterised by high diversity, dominated by trematodes in the central and Tasmanian regions, but with nematodes becoming more prominent in the far northern and southern regions. No core or secondary species were found in the Queensland helminth communities, the southern community was suggestive of a bimodal distribution and the Tasmanian had two core species. A checklist of helminth species occurring in water-rats from eastern Australia is provided.

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Seasonal occurrence of some larval stages of endoparasites in three cyprinids from the Nwanedi-Luphephe dams, the Limpopo River System, South Africa

Helminthologia ◽

10.1515/helmin-2015-0037 ◽

2015 ◽

Vol 52 (3) ◽

pp. 229-235 ◽

Cited By ~ 2

Author(s):

E. M. Mbokane ◽

J. Theron ◽

W. J. Luus-Powell

Keyword(s):

Developmental Stages ◽

River System ◽

Intestinal Wall ◽

The Body ◽

Seasonal Occurrence ◽

Seasonal Fluctuations ◽

Metazoan Parasites ◽

Larval Stages ◽

Parasite Communities ◽

Third Stage

Abstract This study provides information on seasonal occurrence of developmental stages of endoparasites infecting three cyprinids in the Nwanedi-Luphephe dams, Limpopo River System. Labeobarbus marequensis (Smith, 1841), Barbus trimaculatus Peters, 1852 and Barbus radiatus Peters, 1853 were investigated seasonally from January 2008 to October 2008. The following larvae of metazoan parasites were collected: Diplostomum sp. from the eyes of L. marequensis and B. trimaculatus; Ornithodiplostomum sp. from the gills of B. trimaculatus; Posthodiplostomum sp. from muscle, skin and fins of B. trimaculatus and B. radiatus; third-stage Contracaecum larvae (L3) from the mesentery fats and on the liver lobes of L. marequensis and B. trimaculatus and gryporynchid cestode larvae from the outer intestinal wall of B. radiatus. All the flukes encountered were metacercariae. Diplostomum sp. and Contracaecum sp. dominated the parasite communities. Their prevalence exhibited seasonal fluctuations with maxima in summer. Factors likely to influence fish infection such as the body size of fish and their condition factors were also briefly considered in this study.

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