Give any 5 examples of protochordata.

The protochordate animals are bilaterally symmetrical and triploblastic. They have a coelom. A new body feature that is seen in these animals is the presence of notochord at some stage in their life cycle. Due to this very presence of a notochord, they are called as chordates. However, it is sometimes rudimentary.

Examples are: Herdmania, Balanoglossus, Saccoglossus, Amphioxus, Doliolum, Salpa.

They all have these similar characteristics because of which they are the examples of protochordates:

• They are exclusively marine animals.

• Central nervous system is dorsal, hollow and single.

• Pharynx perforated by Gill slits.

• Heart is ventral

• A post anal tail is present.

• Gut is ventral to nerve chord.

• Absence of cranium or brain box.