Key To The Aplousobranchia

Usually colonial (exceptions Ciona, and some species of Diazonidae, Clavelinidae and Euherdmaniidae); gut loop posterior to pharynx; gonads in, or posterior to, gut loop.

1. Gut loop horizontal (Ciona) Cionidae

- Gut loop vertical 2

2. Apertures smooth-rimmed 3

- Apertures not smooth-rimmed 4

3. Abdomen about twice the length of the large thorax (Clavelina, Nephtheis)

Clavelinidae

- Abdomen many times the length of the thorax (Pycnoclavella)

Pycnoclavellidae

4. Internal longitudinal branchial vessels or vestiges of them present; gonads in the abdomen (Diazona, Rhopalaea) Diazonidae

- Lacking internal longitudinal branchial vessels or vestiges of them except when gonads in a posterior abdomen 5

5. Transverse thoracic muscles forming a continuous coat (Polycitor, Eudistoma)

Polycitoridae

- Transverse thoracic muscles not forming a continuous coat 6

6. Stigmata in only three rows (Pseudodistoma, Sigillina) Pseudodistomidae

- Stigmata in more than three rows 7

7. Gonads in the abdomen 8

- Gonads in the posterior abdomen 10

8. Excurrent apertures of zooids opening directly to the exterior; apertures with fringed lobes (Stomozoa) Stomozoidae

- Excurrent apertures not opening directly to the exterior; lobes of the apertures not fringed 9

9. Replicates by horizontal division of a posterior abdominal stolon (Distaplia, Sycozoa, Hypsistozoa) Holozoidae

- Replicates by oesophageal budding (Atriolum, Leptoclinides, Polysyncraton, Didemnum, Trididemnum, Lissoclinum, Didemnidae) Didemnidae

10. Excurrent apertures open directly to the exterior 11

- Excurrent apertures do not open directly to exterior (Polyclinum, Synoicum, Aplidium, Aplidiopsis Polyclinidae

11. Stomach at the end of a relatively long abdomen (Euherdmania) Euherdmaniidae

- Stomach in the middle of a relatively short abdomen 12

12. Posterior abdomen short tapering, with bunched testis follicles) (Pseudodiazona, Monniotus, Protopolyclinum, Condominium) Protopolyclinidae

- Posterior abdomen long, testis follicles not bunched (Ritterella) Ritterellidae

Going Green For More Cash

Going Green For More Cash

Stop Wasting Resources And Money And Finnally Learn Easy Ideas For Recycling Even If You’ve Tried Everything Before! I Easily Found Easy Solutions For  Recycling Instead Of Buying New And Started Enjoying Savings As Well As Helping The Earth And I'll Show You How YOU Can, Too! Are you sick to death of living with the fact that you feel like you are wasting resources and money?

Get My Free Ebook


Post a comment