Ben Thornes

Ciliates in Chalk-stream habitats congregate in biodiversity hot spots

Wednesday 16th July 2014

Free-living ciliates are a diverse group of microbial eukaryotes that inhabit aquatic environments. They have a vital role within the ‘microbial loop’, being consumers of microscopic prey such as bacteria, micro-algae, and flagellates, and representing a link between the microscopic and macroscopic components of aquatic food webs.

This investigation describes the ciliate communities of four habitats located in the catchment of the River Frome, the major chalk-stream in Southern Britain. The ciliate communities were characterised in terms of community assemblage, species abundance and size classes.

The ciliate communities investigated proved to be highly diverse, yielding a total of 114 active species. An additional 15 ‘cryptic’ ciliate species were also uncovered. Heterogeneity in the ciliate communities was evident at multiple spatial scales, revealing hot spots of species richness, both within and between habitats. The ciliate communities of habitats with flowing water were composed of smaller ciliates compared to the still-water habitats examined.

Image 1: The ciliate Nassula tumida, a proficient predator of filamentous cyanobacteria, with a filament in the process of being ingested through the ciliates mouth.

Image 2: The freshwater ciliate Euplotes daidaleos with endosymbiotic algae of the genus Chlorella – the circular green particles.

Image 3: The ciliate Vorticella sp. attached the the surface of the diatom Tabellaria.

Image 4: The River Frome – photo taken near the Freshwater Biological Association’s River Laboratory in East Stoke, Dorset.

Read the full article here.

Find out more about Dr Genoveva Esteban and her research in cryptic biodiversity here.

  • Be the first to comment below...