Chilika Lagoon is a highly productive ecosystem. Its shallow depth supports a high diversity of benthic organisms, planktonic community and aquatic macrophytes. Diatoms are a dominant group found in Chilika lagoon. Diatoms are single-celled photosynthetic algae, abundant in aquatic environment. It is a primary producer of the aquatic environment and they are the primary food source for many aquatic species ranging from microscopic zooplankton to many types of invertebrates to fishes. On our field visit to the southern sector of the lagoon we noticed a light brown scum attached to seaweeds and rocks. We collected the sample and mounted on a slide to observe them under Foldscope.

When analysed under foldscope they were identified to be Biddulphia sp. under the group diatom. Its Cells are robust, rectangular in girdle view, elliptical in valve view, with prominent elevations at the poles. Often occurs in zig-zag chains generally found near shore or attached to substrates such as seaweeds and rock.