Rotifers comprise a modestly sized phylum (≈1,850 species) of tiny (ca. 50–2,000 μm), bilaterally symmetrical, eutelic metazoans, traditionally grouped within the pseudocoelomates or Aschelminthes. These saccate to cylindrically shaped protostomes possess three prominent regions (corona, trunk, foot). They are distinguished by a ciliated, anterior corona (used in locomotion and food gathering) and a pharynx equipped with a complex set of jaws. Unfortunately, these generalizations grossly oversimplify a rich and fascinating diversity. Chief among the charms of the study of rotifers are their ecological importance, ease of culture (including chemostat technology), and the fact that much remains unknown about this exquisite phylum.
While separated by large expanses of dry terrain unsuitable for aquatic biota, aridland waters possess high biodiversity. How aquatic micrometazoans disperse to, and colonize, these isolated ephemeral habitats are not well understood. We used a multi‐faceted approach including wind tunnel and rehydration experiments, and next‐generation sequencing to assess potential movement of diapausing propagules of aquatic invertebrates by anemochory across regional scales (102–105 km). Wind tunnel experiments using dry playa sediments with added micrometazoan propagules demonstrated that after entrainment by saltation and downwind transport, propagules could be subsequently rehydrated and were viable. Further, rehydration of fallen natural dust yielded micrometazoans, including rotifers, gastrotrichs, microcrustaceans, and nematodes. Using conserved DNA primers, we identified > 3300 eukaryotic Operational Taxonomic Units (excluding fungi) in the dust including some taxa found in rehydration experiments. Thus, we provide strong evidence that anemochory can disperse micrometazoans among isolated, ephemeral ecosystems in North American deserts and likely elsewhere.
In spite of considerable efforts over past decades we still know relatively little regarding the biogeography of rotifers of inland waters in México. To help rectify this we undertook an extensive survey of the rotifer fauna of 48 water bodies in the Chihuahuan Desert of México.