ORDER : POLYCLADIDA
Sub order : ACOTYLEA
Super family : Stylochoidea
Family : Callioplanidae
Family : Planoceridae
Super family : Leptoplanoidea
Family : Cestoplanidae

Super family : Stylochoidea Poche, 1926

Callioplanidae Hyman, 1953

- Stylochoidea with ruffled pharynx and mouth more or less in the centre of the body

- The family contains 12 genera, but Callioplana is the only genus treated here.

- The different genera are separated on details of their reproductive structure


Callioplana      Stimpson, 1857

Ethymology :
      - Calli = beautiful, plana = wanderer

Ventral characteristics :
      - A large ruffled and usually centrally placed pharynx is present
      - The male and female gonopores are separate ans located in the posterior region, behind the pharynx
      - A Lang's vesicle is posterior to the female gonopore

Dorsal characteristics :
      - These flatworms have an oval to rounded body with prominent non-retractile head (nuchal) tentacles
      - The head tentacles carry numerous eyes and cerebral eyes are present as two clusters betweeen the head tentacles

Identification :
      - Species identifications are based on details of the reproductive anatomy that can only be determined from microscopic examination of internal anatomy.


Planoceridae Lang, 1884

- Stylochoidea with ruffled pharynx arranged centrally or somewhat anterior to the center of the body

- Planoceridae comprise about 6 genera, but Paraplanocera is the only genus treated here.

- Identification are based on details of the copulatory structures and the arrangement of the eye


Paraplanocera     Laidlaw, 1903

Ethymology :
      - Para = near, plana = wanderer, cera = horns

Ventral characteristics :
      - The pharynx is ruffled and the mouth lies centrally
      - The male and female gonopores are separate ans located in the posterior region, behind the pharynx
      - A Lang's vesicle is posterior to the female gonopore

Dorsal characteristics :
      - These flatworms have an rounded to oval body. They have conspicuous head tentacles which are held erect over the brain region.
      - Both tentacular and cerebral eyes are present

Identification :
      - Species are identified by colour pattern and detail of the reproductive anatomy especially the arrangement of the cirrus spines
      - Worms in this genus include some of the largest os the acotyleans, some up to 12 cm long


Super family : Leptoplanoidea Faubel, 1984

Cestoplanidae Lang, 1884

- Cestoplanidae have an extreme long and distinctly ribbon-like body without tentacles. The margin is hightly ruffled

- This family may be confused with the Cotylean family, Prothiostomidae, however, Cestoplanidae are usually much longer and, of course, lack a true sucker.

- According Newman (2003) probably only single genus is recognized


Cestoplana     Lang, 1884

Ethymology :
      - Cesto = girdle or belt for the shape of the worm, plana = wanderer

Ventral characteristics :
      - The pharynx is ruffled and usually lies posteriorly, the mouth is central.
      - The male and female gonopores are separate and posterior to the pharynx

Dorsal characteristics :
      - Tentacles are absent
      - They have numerous eyes along the anterior margin, but lack true cerebral or tentacular eyes.

Identification :
      - Species are identified on the details of the reproductive structures only visible from serial sections and microscopic examination of the internal anatomy.
      - When disrupted the animal tends to curl into a tangled ball.

 


Publications :

Faubel, A. (1983). The Polycladida, Turbellaria. Proposal and establishment of a new system. Part I. The Acotylea . Mitteilungen aus dem Hamburgischen zoologischen Museum und Institut 80 : 17121
    Newman, L.J. & Cannon, L.R.G. (2003). Marine Flatworms: the world of Polyclads. CSIRO Publishing : Melbourne 112