| 
        
          
            | Olive 
            flatworm Tytthosoceros lizardensis*
 Family 
            Pseudocerotidae
 updated Feb 2020
 Where 
            seen? Many of this large greenish brown flatworm are sometimes 
            seen at night, on coral rubble, among seaweeds and seagrasses, on some of our shores. The flatworm is named in honour of the Lizard Island Research Station in Australia.
 
 Features: 8-10cm. Usually with deep ruffles.  Body mottled brown or olive with white dots forming irregular bars perpendicular to the body edge. Margin comprises  fine white outer edge with fine black inner edge. Underside 
            is uniformly pale with the same margins as the upper side. It has a pair of  
            pseudotentacles that are pointed, ear-like made up of simple folded edges of 
            the body, with white tips. It can swim by 
            undulating its body edges.
 |  
        
          |  Beting Bronok, Jun 18 Photo shared by Loh Kok Sheng on facebook.
 |  |  
         
          |  Tanah Merah, Jul 09
 |  Underside.
 |  |  *Species are 
      difficult to positively identify without close examination.
 On this website, they are grouped by external features for convenience of 
      display.
 
 
        
          
            | Olive 
      flatworms on Singapore shores |  
 
        
          
            | Other sightings on Singapore shores |  
 
        
          |  Changi, Mar 17
 Photo shared by Marcus Ng on facebook.
 |  Chek Jawa, Aug 20
 Photo shared by Jianlin Liu on facebook.
 |  |  
 
        
          |  Beting Bronok, May 09
 Photo shared by Loh Kok Sheng on his blog.
 |  Beting Bronok, May 11
 Photo shared by Loh Kok Sheng on his blog.
 |  
 
        
          |  Beting Bronok, Nov 11
 Photo shared by Loh Kok Sheng on his blog.
 |  Beting Bronok, Jun 16
 Photo shared by Rene Ong on facebook.
 |  Beting Bronok, Jun 16
 Photo shared by Rene Ong on facebook.
 |  
 
        
          |  Kusu Island, Dec 18
 Photo shared by Loh Kok Sheng on facebook.
 |  Big Sisters' Island, Feb 2024
 Photo shared by Richard Kuah on facebook.
 |  Pulau Semakau (South), Nov 24
          Photo shared by Loh Kok Sheng on facebook. |  
 
        
          
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            |  |  
 
         
          | AcknowledgementGrateful thanks to Rene Ong for sharing details and identifying  the flatworms on this page.
 
 Links
 References 
             
              Rene S.L. Ong and Samantha J.W. Tong. 29 October 2018. A preliminary checklist and photographic catalogue of polyclad flatworms recorded from Singapore. Nature in Singapore 2018 11: 77–125.D. M. Bolaños, B. Q. Gan & R. S. L. Ong. 29 Jun 2016. First records of pseudocerotid flatworms (Platyhelminthes: Polycladida: Cotylea) from Singapore: A taxonomic report with remarks on colour variation.(pdf) The Raffles Bulletin of Zoology Supplement No. 34: 130-169  Pp. 130-169.Rene S. L. Ong. 31 August 2016. Aggregation of Tytthosoceros lizardensis flatworms at Beting Bronok. Singapore Biodiversity Records 2016: 108-109.Rene Ong, Samantha Tong & Teresa Stephanie Tay. 13 November 2015. Marine flatworms at Seringat Kias. Singapore Biodiversity Records 2015: 182-184.Humann, Paul 
                and Ned Deloach. 2010. Reef 
                  Creature Identification: Tropical Pacific New World Publications. 
              497pp. Newman, L.J and Cannon, L.R.G. 1996. Bulaceros, new genus, and Tytthosoceros, new genus, (Platyhelminthes: Polycladida) from the Great Barrier Reef, Australia and Papua New Guinea. The Raffles Bulletin of Zoology 44(2): 479-492. |  |  |