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The presence of the rotifer Keratella cochlearis (Gosse, 1851) is reported in El Junco Lake, a freshwater crater lake in San Cristóbal Island, Galápagos Islands. This taxon is a known species aggregate containing both eurytopic cosmopolitans as well as local and regional endemics, but also some insufficiently documented cryptic species. This record is the first of a representative of the aggregate for the rotifer fauna of the Galápagos Islands. Considering that the animal is now being recorded from the lake while earlier surveys did not, and the high dispersal capacity of many rotifers, we hypothesize that the organism recorded is one of the more widespread members of the aggregate, which colonized El Junco Lake only recently.

During the study of rotifers collected in Eastern DR Congo, we rediscovered specimens that correspond to Monostyla dorsicornuta Van Oye, 1926. This species, which we redescribe, had not been seen since it’s summary description, and lacked type material. Our analysis reveals that the animal belongs to Trichotriidae rather than to Lecane (presently considered to include Monostyla) or Lecanidae, but is nevertheless characterised by a foot structure that is remarkably convergent to that of Lecanidae, and different from all other genera of Trichotriidae.We conclude that the species and the closely related South American Macrochaetus kostei (José de Paggi, Branco & Kozlowsky-Suzuki, 2000) belong to a new genus of Trichotriidae; the two offer a rare example of African-South American vicariance in rotifers.We further provide emended diagnoses of the remaining genera of Trichotriidae, to conform these to the new information and to address some inconsistencies in these.

Following previous reports indicating a remarkable high diversity of sessile rotifers in Southeast Asian freshwaters, we report on an extensive study of the diversity of Collothecidae rotifers from fifteen freshwater habitats in Thailand. A total of 13 species, including two additional infraspecific variants, of Collothecidae are recorded, one of which is described as a new species of Collotheca. We further add taxonomic remarks on some of the taxa on record and illustrate the uncinate trophi of several representatives by scanning electron microscopic images. Finally, we provide illustrated identification keys to the Collothecidae recorded to date from Southeast Asia.