Question

Which one of these is wrong on the basis of classification?

• A. Sycon - Calcarea
• B. Euplectella - Hexactinellida
• C. Hyalonema - Demospongia
• D. Spongilla - Demospongia

Answer 1

The correct option is C Hyalonema - Demospongia

Sycon is a genus of calcareous sponges, which are small.
Euplectella or Venus's-flower-basket belongs to the Hexactinellida sponge and inhabiting deep ocean.

Hyalonema belongs to the Hexactinellida. It is called as glass rope sponge. It has amphidisc spicules.

The skeleton of Spongilla consists mainly of spongin fibres, which may be in combination with spicules and comes under the class Demospongiae. Thus, the correct answer is option C.