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Investigations on the parasites that infect migrating birds worldwide are ongoing. To identify the parasite species that infect ardeids, morphological and morphometric characteristics were used. A total of 20 Bubulcus ibis (Ardeidae) specimens were collected from the agricultural lands belonging to the Faculty of Agricultural at Cairo University, which were then examined for nematode parasites. Only one acuariid species, belonging to the Acuariidae family, has been identified, with a prevalence rate of 50 % (10/20) among infected egrets. The Desportesius species isolated from the gizzard of the egret host is morphologically and morphometrically compatible with Desportesius invaginatus , which was previously identified from several Ciconiiformes hosts of Bubulcus ibis (Egypt, India, and Taiwan), Egretta garzetta (France), and Egretta rufescens (USA). Additionally, utilizing the partial small subunit ribosomal RNA (18S rRNA) gene sequence, maximum parsimony based on the Tamura-Nei model was used to infer the phylogeny of the recovered Desportesius species. The query sequences revealed 99.37 % identity for the 18S (MW358651.1) of the previously mentioned D. invaginatus. In addition to clarifying several morphological features of D. invaginatus , this study also provided new DNA data for this species. [ABSTRACT FROM AUTHOR]

Human induced ecosystem alterations and climate change are expected to drive several species to extinction. In this context, the attention of public opinion, and hence conservationists' efforts, are often targeted towards species having emotional, recreational and/or economical value. This tendency may result in a high number of extinctions happening unnoticed. Among these, many could involve parasites. Several studies have highlighted various reasons why we should care about this, that go far beyond the fact that parasites are amazingly diverse. A growing corpus of evidence suggests that parasites contribute much to ecosystems both in terms of biomass and services, and the seemingly paradoxical idea that a healthy ecosystem is one rich in parasites is becoming key to the whole concept of parasite conservation. Although various articles have covered different aspects of host–parasite co-extinctions, I feel that some important conceptual issues still need to be formally addressed. In this review, I will attempt at clarifying some of them, with the aim of providing researchers with a unifying conceptual framework that could help them designing future studies. In doing this, I will try to draw a more clear distinction between the (co-)evolutionary and the ecological dimensions of co-extinction studies, since the ongoing processes that are putting parasites at risk now operate at a scale that is extremely different from the one that has shaped host–parasite networks throughout million years of co-evolution. Moreover, I will emphasize how the complexity of direct and indirect effects of parasites on ecosystems makes it much challenging to identify the mechanisms possibly leading to co-extinction events, and to predict how such events will affect ecosystems in the long run. [ABSTRACT FROM AUTHOR]

Speciation in sexually reproducing organisms hinges on reproductive barriers that reduce gene flow between species or preclude the formation of hybrids. Here, we studied potential reproductive barriers in four members of the Epichloë typhina (Ascomycota, Clavicipitaceae) complex, i.e. Epichloë typhina infecting Dactylis glomerata , E. typhina subsp. clarkii infecting Holcus lanatus , E. typhina subsp. poae infecting Poa nemoralis and E. typhina infecting P. trivialis . Reciprocal inoculation tests showed that these endophytes are host-specific. This suggests that reproductive isolation among Epichloë strains may be the result of specialization to one host, on which mating between different individuals occurs. Furthermore, significantly lower infection frequencies of F1 progeny from crosses between host-strains compared to parental strains and within host-strain progeny suggest that host-dependent effects upon hybrid fitness exist, which would conform to an extrinsic postzygotic isolation barrier. Our results may explain, why members of the E. typhina complex remain genetically differentiated in natural populations. [ABSTRACT FROM AUTHOR]

Groupers are large predators in the Serranidae family that feed on fish and small invertebrates. Identification of parasitic taxa of groupers was done concerning their morphological and biological characteristics. A total of 30 Cephalopholis sonnerati (Serranidae) specimens were investigated for digenetic trematodes in the Red Sea, Saudi Arabia. Only one bivesiculid species, belonging to the Bivesiculidae family, has been identified, with a prevalence rate of 60% (18/30) among infected fish. The Bivesicula species obtained from the fish host's intestine is morphologically and morphometric compatible with Bivesicula claviformis , which was previously identified from Epinephelus fasciatus (Serranidae) in North Borneo. In addition, maximum parsimony based on Tamura-Nei model was utilized to determine the phylogeny of the recovered Bivesicula species using partial small subunit ribosomal RNA gene (18S rRNA) and large subunit ribosomal RNA gene (28S rRNA) sequences. The query sequences showed the identities of 99.39% and 94.02% for 18S (AJ287485.1) and 28S rRNA (AY222182.1) of the previously described Bivesicula claviformis , respectively. The present study demonstrated that Bivesicula claviformis is the first reported of this genus as endoparasites from C. sonnerati , as well as providing novel DNA data for this species. [ABSTRACT FROM AUTHOR]

Abstract: Insect mycophagy is considered common but generally lacking host-specificity. Larvae of some Mycodiplosis species (Insecta, Diptera) feed primarily on spores of rust fungi (Basidiomycota, Pucciniales). The number of rust-feeding species and their relative frequency, distribution, and degree of host-specificity are not known. A survey of 200 recent rust collections from around the world, and a systematic survey of 333 herbarium specimens from Maryland show that Mycodiplosis infestation is very common. Desiccated larvae were found on specimens dating back as far as 1886, the oldest collection in the survey. Greater than 20% of all rust collections examined were infested with Mycodiplosis larvae. In Maryland infestation frequencies were similar at different spatial scales, but different rust species varied in their frequency of infestation. Primers were designed to target Mycodiplosis 28S rDNA, and sequence data revealed genetic variation between Mycodiplosis isolates from different rust species. [Copyright &y& Elsevier]

Fungal endophyte (FE) communities can be shaped by environmental conditions and/or host-plant affinities. Hawaiʻi's landscape-dominant woody genus Metrosideros (Myrtaceae) comprises several vegetatively distinct taxa that are non-randomly distributed across environments, and their FE communities are poorly known. We examined the relative importance of Metrosideros taxon and environment (elevation) on FE communities on Oʻahu. ITS1 rDNA barcoding and sequencing of 113 trees detected a richness of 1,637 FEs representing 5 phyla, 223 genera, and 200 species. Variation in FE diversity was significantly explained by host taxon and site with considerable overlap in FE communities among taxa. FE communities did not vary between pubescent and glabrous taxa or across elevations, possibly due to the relatively narrow range of environmental conditions represented on Oʻahu relative to taller islands. A significant pattern of isolation by distance in FE composition was detected both among and within sites, consistent with restricted dispersal of FEs across the island. [ABSTRACT FROM AUTHOR]

Fungus-growing termites (subfamily Macrotermitinae) live in an obligate mutualistic symbiosis with species of the fungal genus Termitomyces (Basidiomycota). Although the species that build large mounds are the most conspicuous, termites of the genus Microtermes construct large underground networks of tunnels connecting many fungus gardens. They are also the only entire genus within the Macrotermitinae in which vertical transmission of the fungal symbiont has evolved. To study patterns of genetic diversity in species of the genus Microtermes and their Termitomyces symbionts, we sampled at three different locations in South Africa and sequenced COI for the termites and ITS for the fungi. We discovered high genetic diversity in both termites and fungal symbionts but very low interaction specificity. This implies that frequent horizontal exchange of fungal symbionts occurs between species, despite vertical transmission across generations. We also estimated colony size based on termite haplotype and fungal genotype combinations and found indications that colonies may extend over large areas. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To observe their specificity, speciation and ecological equivalence by using previous and present records, from freshwater fish from Tanakpur to Sultanpur areas, during 2009 & 2010. Methods: Data is gathered from the published records to compare it with the present records and entered into a computer database. The taxonomy of monogenoideans follows and those of fish follows. The worms were gently scrapped from the gills of fish and counted manually. They were studied mostly live, under a phase contrast microscope (Olympus CX 41 U-DA 4E 03365 Japan) or fixed in 3% formalin, after being relaxed in lukewarm water. Results: These monogenoids have perfect ecological equivalence, as their macro habitat is geologically connected. They exhibit specificity at different taxonomic levels of the parasites and the hosts. Sympatric speciation of parasites and their host is evident in the present study. Conclusions: The monogenoidean fauna, in this region, has its species integrity in the past sixty to sixty five years. From this important body of study, it seems likely that host specificity among monogenoids from the fresh water fish is more widely spread than previously thought. Seasonal variations, probable controlling factor of infection, determine the intensity. [Copyright &y& Elsevier]