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Sociality is not common among parasitoid hymenopterans, but members of the ectoparasitoid genus Sclerodermus (in the aculeate family Bethylidae) may form multi‐foundress groups, producing and tending a single brood (of combined parentage) on a large host until offspring maturity. While individual foundresses can benefit more from reproducing within groups rather than alone, recent studies have indicated that there are conflicts of interest between co‐foundresses at the time of host suppression and during brood production, some of which may be mediated by intrinsic or acquired dominance. Evidence for overtly agonistic interactions has, however, been lacking.Here, we report that resident Sclerodermus guani Xiao et Wu females that have suppressed a host, can either accept introduced intruder females as co‐foundresses without aggression or repel, and even kill, intruders by biting and stinging them.Residents were more likely to exhibit aggression when they had commenced oviposition, when more days had passed since oviposition, when they were larger than the intruder, when the intruder was a non‐sibling, or when they were the sole resident rather than being in a group of two residents.We conclude that cooperatively brooding in Sclerodermus can be conditional on the evolutionary interests of foundresses with temporal priority on a host and their ability to repel potential co‐foundresses. [ABSTRACT FROM AUTHOR]

Little is known about ocean viromes and the ecological drivers of the evolution of aquatic RNA viruses. This study employed a meta-transcriptomic approach to characterize the viromes of 58 marine invertebrate species across three seas. This revealed the presence of 315 newly identified RNA viruses in nine viral families or orders (Durnavirales, Totiviridae, Bunyavirales, Hantaviridae, Picornavirales, Flaviviridae, Hepelivirales, Solemoviridae, and Tombusviridae), with most of them being sufficiently divergent to the already documented viruses. Notably, this study revealed three marine invertebrate hantaviruses that are rooted to vertebrate hantaviruses, further supporting that hantaviruses may have a marine origin. We have also found evidence for possible host sharing and switch events during virus evolution. Overall, we have revealed the hidden diversity of marine invertebrate RNA viruses. [ABSTRACT FROM AUTHOR]

Bats harbour diverse coronaviruses (CoVs), some of which are associated with zoonotic infections, as well as inter‐species transmission. In this study, a total of 512 bat faecal samples from the bat habitats at different geographical locations in South Korea were investigated between 2016 and 2019. Seventy‐eight samples were positive for coronaviruses (15.2%), comprising 68 alphacoronaviruses (13.3%) and 10 betacoronaviruses (2.0%). The positive rates tended to increase during the awakening (April) period. Notably, betacoronaviruses were only found in the site where Rhinolophus ferrumequinum was the major species of bats, and were related to SARS‐ and MERS‐related CoVs identified in China and South Korea, respectively. No betacoronaviruses were closely related to SARS‐CoV‐2 in this study. Alphacoronaviruses were detected in the sites where Hypsugo alaschanicus, Miniopterus fuliginosus, Miniopterus schreibersii, Rhinolophus ferrumequinum, Myotis bombinus, Myotis macrodactylus and Myotis petax were found to be the major bat species. Furthermore, alphacoronaviruses had higher genetic diversity than betacoronaviruses and had a wider distribution in Korea. Considering that different bat species are co‐roosting in crowded conditions in the same habitat, the diverse coronaviruses in Korean bats are likely to undergo cross‐species transmission events due to the richness in host species. Therefore, continuous monitoring should be performed, especially at the awakening time of the hibernating bats in the habitats where diverse bat species co‐roost, to better understand the evolution of coronaviruses in bats. [ABSTRACT FROM AUTHOR]

Kinship among interacting individuals is often associated with sociality and also with sex ratio effects. Parasitoids in the bethylid genus Goniozus are sub‐social, with single foundress females exhibiting post‐ovipositional maternal care via short‐term aggressive host and brood defence against conspecific females. Due to local mate competition (LMC) and broods normally being produced by a single foundress, sex ratios are female‐biased. Contests between adult females are, however, not normally fatal, and aggression is reduced when competing females are kin, raising the possibility of multi‐foundress reproduction on some hosts. Here, we screen for further life‐history effects of kinship by varying the numbers and relatedness of foundresses confined together with a host resource and also by varying the size of host. We confined groups of 1–8 Goniozus nephantidis females together with a host for 5+ days. Multi‐foundress groups were either all siblings or all nonsiblings. Our chief expectations included that competition for resources would be more intense among larger foundress groups but diminished by both larger host size and closer foundress relatedness, affecting both foundress mortality and reproductive output. From classical LMC theory, we expected that offspring group sex ratios would be less female‐biased when there were more foundresses, and from extended LMC theory, we expected that sex ratios would be more female‐biased when foundresses were close kin. We found that confinement led to the death of some females (11% overall) but only when host resources were most limiting. Mortality of foundresses was less common when foundresses were siblings. Developmental mortality among offspring was considerably higher in multi‐foundress clutches but was unaffected by foundress relatedness. Groups of sibling foundresses collectively produced similar numbers of offspring to nonsibling groups. There was little advantage for individual females to reproduce in multi‐foundress groups: single foundresses suppressed even the largest hosts presented and had the highest per capita production of adult offspring. Despite single foundress reproduction being the norm, G. nephantidis females in multi‐foundress groups appear to attune sex allocation according to both foundress number and foundress relatedness: broods produced by sibling foundresses had sex ratios similar to broods produced by single foundresses (ca. 11% males), whereas the sex ratios of broods produced by nonsibling females were approximately 20% higher and broadly increased with foundress number. We conclude that relatedness and host size may combine to reduce selection against communal reproduction on hosts and that, unlike other studied parasitoids, G. nephantidis sex ratios conform to predictions of both classical and extended LMC theories. [ABSTRACT FROM AUTHOR]

Hosts that overlap geographically, are less phylogenetically divergent, and/or share similar ecological conditions (e.g., climate, habitat type) are also likely to share parasites. Here we assessed the ectoparasite communities sustained by 3 solitary species of Bathyergidae (Georychus capensis, Bathyergus suillus, and Bathyergus janetta) as well as the endoparasites exploiting G. capensis and compared them with those reported in the literature for other sympatric and parapatric African mole-rat species. In addition to 1 nematode (Trichuris sp.) and 1 symbiotic ciliate (Meistoma georychi), we collected mites of the genera Androlaelaps and Bathyergolichus as well as unidentified trombiculids from these hosts. Host specificity was high at either the species, genus, or family level for Androlaelaps spp. and Bathyergolichus spp. irrespective of geographic proximity, host phylogeny, or ecological conditions. Host sharing was more limited for helminths but observed among sympatric host species. Our results suggest that ecological similarity and geographic proximity may be more important determinants of host sharing than phylogeny within Bathyergidae. [ABSTRACT FROM AUTHOR]

Abstract: We examined the spatial structure of Schistosoma mansoni, a parasite of humans, from natural infections at two levels: across the Lake Victoria basin of Kenya and among snail hosts. Using 20 microsatellite markers we examined geographic patterns of relatedness and population structure of cercariae and found weak, but significant structure detected by some, but not all analyses. We hypothesise structure created by aggregations of clonal individuals or adherence of hosts to local transmission sites is eroded by high amounts of gene flow in the region. This finding also supports previous hypotheses concerning the evolution of drug resistance in the region. Intrasnail dynamics were investigated in the context of aggregation and kin selection theory to determine how relatedness and also sex influence host sharing and host exploitation. Cercarial production did not differ significantly between snails with one or two genotypes suggesting that mixed infections resulted in decreased individual fitness and provides a framework for reproductive competition. Coinfection patterns in snails were independent of parasite relatedness indicating that schistosomes were not aggregated according to their relatedness and that kin selection was not influencing host sharing. Additionally, host exploitation in coinfections (measured by cercarial production) was not negatively correlated with relatedness, as predicted by classical models due to increased competition and thus exploitation when parasites are unrelated. Because of the low levels of relatedness within the population, schistosomes may rarely encounter close relatives and kin selection mechanisms that influence the distribution of individuals within snails or the virulence mode of the parasites may simply have not evolved. [Copyright &y& Elsevier]