IDENTIFICATION (with reason) OF Herdmania sp. (B.Sc. ZOOLOGY_CCF- SEMESTER5_DSCC-9)

   Identifying features are:

1. Multicellular heterotroph.
2. embryonic development, preceded by heterogametic fertilization.

            Hence, the specimen belongs to the Kingdom Animalia.

1. Presence of hollow, dorsal, tubular nerve cord.
2. Presence of notochord, at any stage of their life or throughout the life.
3.  Presence of pharyngeal gill slits & post anal tail during some stage in the ontogeny.

            Hence, the specimen belongs to the Phylum Chordata.

1. Body enclosed in a test.
2. Pharyngeal clefts open in an atrium.

           Hence, the specimen belongs to the Sub Phylum Urochordata.

1. The test is permanent & thick.
2. Atrial aperture opens dorsally.
3. Mouth is terminal.

          Hence, the specimen belongs to the Class: Ascidiacea

1. Undivided, compact body.
2. Neural gland dorsal or lateral to ganglion.
3. Gonads 2 or more embedded in mantle wall.
4. Separate eye absent.

          Hence, the specimen belongs to Order: Pleurogona

1. Oblong bag like body divided into a proper body, & a foot.

2. Proper body bears branchial siphon (oral/incurrent aperture) & atrial siphon (excurrent aperture).

3. Both oral & atrial apertures are typically surrounded by four distinct lobes or lips.

4. Protective outer cover is called Tunic or test. It is thick, leathery, composed of tunicin & uniquely reinforced by numerous microscopic calcareous spicules of various shapes.

5. It is a filter feeder, hermaphrodite.

6. Free swimming Tadpole larva is present in their life cycle.

          Hence, the specimen seems to be Herdmania sp.

Systematic Position: (Young,1981)

Kingdom: Animalia

         Phylum: Chordata

             Sub Phylum: Urochordata

                    Class: Ascidiacea

                        Order: Pleurogona

                               Genus: Herdmania