Question

Freshwater sponge is
(A) Euspongia
(B) Spongilla
(C) Cliona
(D) Euplectella

Answer 1

Hint: Euspongia, Cliona and Euplectella, all three are the varieties of marine sponges. Spongilla is a type of freshwater sponge.

Complete answer:
- Spongilla are freshwater sponges belonging to the family Spongillidae and are mostly found in lakes and stagnant streams. The skeleton of Spongilla is composed of siliceous spicules. The reproduction in Spongilla takes place both by sexual and asexual mode.
- The asexual reproidcution takes place by gemmules, and sexual reproduction takes place through an atypical free swimming of larva.
- Euspongia are also known as Bath sponge due to its texture having wooly, sponge-like fibres and is mostly used for scrubbing during bathing. They belong to class Demospongiae of phylum Porifera and are majorly found in the Mediterranean Sea.
- They typically have a globular shape with plentiful oscula accumulated over the canals (distinct projections).
- Cliona are a type of marine sponge and belong to class Demospongiae of phylum Porifera. They are also called a boring sponge due to its practice of boring holes in the oyster shells. This deteriorates the shells and ultimately kills the oysters.
- The Cliona species are the main pests to Bay oysters. Euplectella is a sponge type which belongs to phylum Porifera and is mostly found in the marine. They are also referred to as Venus Flower Baskets.

Note: The species belonging to phylum Porifera are simple and multi-cellular animals. Today, with an average, the number of Poriferans varies between $5000$- $10000$. Most importantly, amongst all these species around 150 species only exist in fresh water and rest live in salt or saline water.