T.E.R:R.A.I.N - Taranaki Educational Resource: Research, Analysis and Information Network


Flatworm (Australoplana sanguinea (Australian flatworm)

Kingdom: Animalia
Phylum: Platyhelminthes
Class: Turbellaria
Order: Tricladida
Suborder: Continenticola
Superfamily: Geoplanoidea
Family: Geoplanidae
Subfamily: Rhynchodeminae
Genus: Australoplana
Species: Australoplana sanguinea
Scientific name: Australoplana sanguinea
Common name: Australian Flatworm

Australoplana sanguinea is a invasive species of flatworm native to Australia and is a predator of earthworms.
It is a medium sized, flattened worm ( 3-8 cm long, 2-5 mm wide). It has no annulations or rings on the body and is completely smooth. The head end is slender and more extendible than the hind end. There is a row of blackish dots visible along the pale margin, being dense and close together near the head but sparse and well separated towards the tail. These are light sensitive organs which help the animal to navigate. The pharynx (mouth) is located on the underside about one third the ways down from the head. The pharynx is pushed out of the body cavity when feeding and envelops the prey, secreting a digestive fluid on to it.
A. sanguinea is a tangerine colour with peach-coloured front end or it can be a pinkish colour after feeding. The underside is a pale buff colour.
It is usually found under stones, planks, and other refuges on damp soil surfaces.

It is thought that this worm can reproduce by fission, worms splitting in two, each half regenerating into a complete worm. Sexual reproduction occurs with egg capsules being laid in the soil. They are first a dull red but after a few hours the chitin of the egg cures to a shiny black. The eggs hatch after several weeks to release one to four small flatworms. The young look like paler miniature versions of the adults.
Adults are usually found between autumn and late spring and are rarely detectable in the summer, probably because they retreat into the soil when the atmosphere is dry.

Flatworm with body contracted 30 mm lenght
  

Body extended. Narrow end is the head.