Land Planarians

20 June, 2010

Land Planarian
Land Planarian
Image: Blackbone Music
Source: Source Flickr

Question: I saw this yellow worm-like creature in the forest, was it just a normal worm?

Answer: The worm could possibly be a ‘land planarian’ or 'terrestrial flatworm' (Phylum: Platyhelminthes, Class: Turbellaria). Turbellarians are mainly aquatic, and the great majority are marine, however several groups are terrestrial.

Land planarians are invertebrate animals meaning they do not have a backbone. You may be surprised to know that 95 per cent of the world’s animals, from sponges and amoeba to starfish and insects, are invertebrates.

Land planarians are generally confined to humid areas where they hide beneath logs and leaf litter during the day, emerging at night to feed. They occur in a variety of habitats ranging from tropical rainforest to arid semi-desert. Land planarians are entirely free living and carnivorous, feeding on small invertebrates such as slugs and earthworms, or on the bodies of dead animals.

Land planarians are hermaphrodites and lay eggs in gelatinous masses under logs and in soil. Asexual reproduction, in which the animal fragments or divides transversely to form two or more individuals, often occurs.

The Australian planarian fauna consists of at least 137 known species belonging to two main families, Rhynchodemidae and Geoplanidae. The total fauna is estimated to be in excess of 300 species (Winsor 1998); eight species are introduced. A third family, ‘Bipaliidae’, consists solely of the introduced cosmopolitan species Bipalium kewense.

Introduced planarians have most likely been accidentally introduced via shipments of plants, soil, or attached to earthmoving & agricultural machinery, and are often associated with gardens, nurseries and other man modified areas.

Comments (8)

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Sarah 31 January, 2011 08:10
Hi, I think a couple of the images in the image gallery here are actually ribbon worms (phylum Nemertea) otherwise great page and very helpful. Cheers
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Discovery Centre 2 February, 2011 16:19

Hi Sarah,

 Images 3 & 4 could possibly be nemerteans.

 Nemerteans (also known as ‘proboscis worms’) can superficially resemble planarians however they can be distinguished from planarians by the presence for an reversible anterior proboscis.  Unfortunately neither of the specimens in these images is displaying their proboscis which makes it difficult to be 100% sure.

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Aaron Taylor 23 April, 2011 10:57
Hi Museum Victoria, I'm in Brisbane - while gardening I uncovered an interesting worm which looked alot like that shown in image 2. Was about 12cm long and displayed a distinctive shovel-like extension at its anterior end. I'm curious to know if the specimen in image 2 would be found in Brisbane, and can you identify in any more detail? Thanks.
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Discovery Centre 4 May, 2011 10:43

Hi Aaron, thanks for the questions.  The description of a ‘shovel head’ is an indication that the worm is most likely the terrestrial flatworm ‘Bipalium kewense’. Turbellarians are mainly aquatic, and the great majority are marine, however several groups are also terrestrial. Terrestrial flatworms are generally confined to humid areas where they hide beneath logs and leaf litter during the day, emerging at night to feed. They occur in a variety of habitats ranging from tropical rainforest to arid semi-desert. They are entirely free living and carnivorous, feeding on small invertebrates such as slugs & earthworms, or on the bodies of dead animals. See the following link: http://australianmuseum.net.au/Shovel-headed-Garden-Worm  for more information.

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Janet 21 June, 2011 17:05
I found about 6 of the flesh coloured flatworms under a polystyrene box used to store worm tea containers. One was nearly 5cm long. This is the first time I've seen anything like these in the garden. I was recommended by Geelong DPI/DSE to contact MV. After checking this website, I was pleased to see images of the flesh coloured Land Planarium which identical to the ones I've found. They were strategically placed - under my worm farm! Thank you for having the images and the info.
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janna 8 December, 2011 23:01
just a quick question about this shovel headed worm .... my dog came in tonight and caught one of them up are they harmless to animals or should i be worried for my pet, it was about 6:30 at night ..... are they known to be in australia ???
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Discovery Centre 9 December, 2011 11:51
Hi Janna, we do have a free identification service but it is helpful to have either the specimen or a good quality image. This link will let you know where to send the image. We don't believe that land planarians pose any significant threat to dogs.
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meredyth sawyer 2 October, 2013 14:40
I have seen black, blue, orange and red flat worms in my garden. I'm concerned about the shovel nosed picture. Is it different from the hammer head worm overseas? I saw information that said hammer heads were destructive to other worms & snails etc. just like out flat worms are when introduced overseas.
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