Marine Biology (2+1)

5.Sagitta sp

Species: Sagittbi punctata

Minor Phylum: Chaetognatha

Order : Aphragmophora

Family : Sagittidae

Description: It is a small chaetognath (arrow worm) with a body comparatively slender, rigid and transparent. The body could be divisible into head,trunk and tail. There are two pairs of lateral fins in the trunk region besides a single tail fin. The posterior fin is slightly larger than the anterior fins and completely rayed. The head bears sickle  shaped spinesaround the mouth, which together form ‘seizing jaw’. The sides of the body are covered with numerous tufts of sensitive papillae. It is a hermaphroditic form, mainly distributed in tropical seas and is considered to be an indicator species.