An official website of the United States government
IntroductionThe long-distance, seasonal migrations of birds make them an effective ecological bridge for the movement of ticks. The introduction of exotic tick species to new geographical regions can cause the emergence of novel tick-borne pathogens. This study examined the prevalence of exotic tick species parasitizing migratory songbirds at stopover sites along the northern Gulf of Mexico using the mitochondrial 12S rRNA gene. MethodsOverall, 421 individual ticks in the generaAmblyomma,Haemaphysalis, andIxodeswere recorded from 28 songbird species, of whichAmblyommaandAmblyomma longirostrewere the most abundant tick genera and species, respectively. A high throughput 16S ribosomal RNA sequencing approach characterized the microbial communities and identified pathogenic microbes in all tick samples. Results and discussionMicrobial profiles showed that Proteobacteria was the most abundant phylum. The most abundant pathogens wereRickettsiaand endosymbiontFrancisella,Candidatus Midichloria, andSpiroplasma. Permutation multivariate analysis of variance revealed that the relative abundance ofFrancisellaandRickettsiadrives microbial patterns across the tick genera. We also noted a higher percentage of positive correlations in microbe-microbe interactions among members of the microbial communities. Network analysis suggested a negative correlation between a)FrancisellaandRickettsiaand, b)FrancisellaandCutibacterium. Lastly, mapping the distributions of bird species parasitized during spring migrations highlighted geographic hotspots where migratory songbirds could disperse ticks and their pathogens at stopover sites or upon arrival to their breeding grounds, the latter showing mean dispersal distances from 421–5003 kilometers. These findings spotlight the potential role of migratory birds in the epidemiology of tick-borne pathogens.
more »
« less
Exotic species of rotifers in Mexico
Abstract Mexico is a megadiverse country, with 10% of all known species found within its borders. The CONABIO catalogue registers rotifers as one of the best-studied groups of animals in Mexico, with the number of species recorded representing 18% of the total global rotifer fauna. However, this registry does not record a single exotic species of Rotifera in Mexico. Here, we confirm the presence of six species of exotic rotifers in Mexican inland waters, highlighting the case of Kellicottia bostoniensis, recorded in Mexico since the 1990’s, but never as an exotic species.
more »
« less
- Award ID(s):
- 2051710
- PAR ID:
- 10399007
- Editor(s):
- Dolan, John
- Date Published:
- Journal Name:
- Journal of Plankton Research
- Volume:
- 44
- Issue:
- 2
- ISSN:
- 0142-7873
- Page Range / eLocation ID:
- 268 to 272
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
More Like this
-
-
The Brissidae is a family of heart urchins that includes shallow‑water, infaunal species, some of which are rarely observed. One species,Rhynobrissus cuneusCooke, 1957, has only been recorded from the western Atlantic off the coast of North Carolina, USA and in the Gulf of Mexico off the coast of Veracruz, Mexico. This work identifies new records from the coast of Florida, USA, increasing our knowledge of this species’ geographic distribution.more » « less
-
Ellermeier, Craig D (Ed.)Host-associated microbial communities profoundly impact the health of humans and other animals. Zebrafish have proven to be a useful model for uncovering mechanisms of host-microbe interactions, but the difficulty of maintaining germ-free or gnotobiotic zebrafish beyond 1 week post-fertilization has limited their utility. To address this, we have developed a simple protocol using UV irradiation of rotifers, a common and nutrient-rich prey species for larval zebrafish, to reduce the bacterial load associated with the rotifers by several orders of magnitude while maintaining their motility and viability. We find that though feeding with UV-treated rotifers does not preserve the sterility of germ-free fish, it enables the maintenance of pre-existing bacterial communities. Normal feeding, in striking contrast, leads to the near-total depletion of these prior populations. We measure the abundance of single- and three-species consortia of zebrafish-commensal bacteria inoculated into initially germ-free larvae in a series of experiments extending to 8 days of feeding, or 13 days post-fertilization. We find, in fish-fed UV-treated rotifers, the persistence of bacterial populations on timescales of days, together with strong species-specific variation. In addition, re-inoculation of differently labeled strains of the same zebrafish-commensal species alongside feeding leads to colonization by the new bacteria without displacement of earlier microbes. Our method will facilitate the use of gnotobiotic zebrafish for investigations of phenomena that emerge later in animal development and for studies that probe microbiome composition fluctuations and stability over extended timescales.IMPORTANCEAll animals, including humans, are host to vast microbial communities that contribute to health and disease through mechanisms that remain largely mysterious. These microbiomes are challenging to study, spurring the use of various model organisms, including zebrafish. Zebrafish, however, are difficult to raise beyond 1 week post-fertilization under gnotobiotic conditions, in other words, germ free or with known microbial constituents, a consequence of normally feeding on live prey that brings their own, generally unknown, microbes. Therefore, we developed a simple protocol in which UV irradiation of rotifers, a widely used small-animal food for larval zebrafish, facilitates the maintenance of gnotobiotic larvae. We show that pre-existing bacterial communities in larvae are minimally affected by feeding on UV-treated rotifers, in strong contrast to feeding on untreated rotifers. We demonstrate that this feeding method allows investigations of zebrafish-associated bacterial community stability over several days, allowing investigation of previously intractable questions about microbiome stability.more » « less
-
Understanding the general biology, biodiversity, ecology, and evolutionary history of organisms necessitates correct identification. Found worldwide in fresh, brackish, and some marine waters, rotifers can be difficult to identify due to their small size, complex characteristics, and dearth of keys to their identification. Moreover, many species lack a hard body wall (i.e., illoricate species), thus they are nearly impossible to identify when preserved. As a result detailed study of many illoricate rotifers is wanting. This is especially acute for the sessile rotifers where quality illustrations, either as line art or light or scanning electron photomicrographs, of adults and trophi is deficient. This leads to a serious impediment in providing a comprehensive accounting for some species. Lacinularia and Sinantherina (Monogononta; Gnesiotrocha; Flosculariidae) are two sessile genera in which the literature provides inadequate treatment. In this contribution we (1) provide simple, dichotomous keys for the identification of all valid species of both genera and (2) present collated information on their morphology thereby detailing where additional research is needed. Both keys focus on easily observable characters of adult female morphology, including features of their coronae, antennae, colony formation behaviors, and presence/absence of eyespots in the adults. We hope that our effort promotes additional research on these two genera, including better documentation of their trophi and general body morphology.more » « less
-
Munderloh, Ulrike Gertrud (Ed.)Microorganisms, including rotifers, are thought to be capable of long distance dispersal. Therefore, they should show little population genetic structure due to high gene flow. Nevertheless, substantial genetic structure has been reported among populations of many taxa. In rotifers, genetic studies have focused on planktonic taxa leaving sessile groups largely unexplored. Here, we used COI gene and ITS region sequences to study genetic structure and delimit cryptic species in two sessile species (Limnias melicerta [32 populations]; L. ceratophylli [21 populations]). Among populations, ITS region sequences were less variable as compared to those of the COI gene (ITS; L. melicerta: 0–3.1% and L. ceratophylli: 0–4.4%; COI; L. melicerta: 0–22.7% and L. ceratophylli: 0–21.7%). Moreover, L. melicerta and L. ceratophylli were not resolved in phylogenetic analyses based on ITS sequences. Thus, we used COI sequences for species delimitation. Bayesian Species Delimitation detected nine putative cryptic species within L. melicerta and four putative cryptic species for L. ceratophylli. The genetic distance in the COI gene was 0–15.4% within cryptic species of L. melicerta and 0.5–0.6% within cryptic species of L. ceratophylli. Among cryptic species, COI genetic distance ranged 8.1–21.9% for L. melicerta and 15.1–21.2% for L. ceratophylli. The correlation between geographic and genetic distance was weak or lacking; thus geographic isolation cannot be considered a strong driver of genetic variation. In addition, geometric morphometric analyses of trophi did not show significant variation among cryptic species. In this study we used a conservative approach for species delimitation, yet we were able to show that species diversity in these sessile rotifers is underestimated.more » « less
- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1093/plankt/fbab093
