Flatworms in Nottinghamshire
Innumerable pages on this website have often opened with a statement describing how little is known about the status of a particular species, Family or Order, but its a statement which certainly applies to Flatworms in Nottinghamshire.

Certainly on both past and present evidence, we probably know nothing of what species we have here, how common they are, or where they actually occur. And the evidence from the hours of research put in, reveals that Flatworms appear to be much less common than might be thought. There again, many people will likely never have  heard of Flatworms.
It was a chance discovery at Woodthorpe Park in Nottingham that's the reason for this page, when some strange, completely black invertebrates on the underside of some large logs alerted my inquisitive side. So I took a couple of record photographs and made my way home to try and identify them.
UK Flatworms

The following is a list of Terrestial Flatworm species with UK records. It's been difficult to compile as there is so little information out there and trying to determine the current nomenclature is difficult. Most of the species names are taken from the NBN Atlas. If there are any mistakes (and I assume there is) please let me know, but I will be making attempts to sort any discrepancies out in the meantime.
Family: Bipaliidae
Genus: Bipalium   Stimpson, 1857

Bipalium kewense (Moseley, 1878)

Family: Geoplanidae
Genus: Arthurdendyus   Jones 1999

Arthurdendyus albidus (Jones & Gerard, 1999) 
Arthurdendyus triangulata New Zealand Flatworm (Dendy, 1895) 

Genus: Artioposthia   Graff, 1896
Artioposthia exulans (Dendy, 1901)

Genus: Australopacifica   Stimpson, 1857
atrata  (Steel, 1897)

Genus: Australoplana   Winsor, 1991
Australoplana alba (Dendy, 1891)
Australoplana sanguinea
Australian Flatworm (Dendy, 1891)

Genus: Caenoplana   Moseley, 1877
Caenoplana bicolor Southampton Flatworm (Graff, 1899)
Caenoplana coerulea
(Moseley, 1877)

Genus: Kontikia  Froehlich,1954  
Kontikia andersoni (Jones, 1981)  
Kontikia ventrolineata (Dendy, 1892)

Genus: Marionfyfea   Winsor, 2011
Marionfyfea adventor (Jones & Sluys, 2016)

Family: Obama   Carbayo et al., 2013

Obama nungara
Obama Flatworm Carbayo, Álvarez-Presas, Jones & Riutort, 2016 

Genus: Parakontikia   Winsor, 1991
Parakontikia coxii (Fletcher & Hamilton, 1888)

Family: Rhynchodemidae
Genus: Dolichoplana
   Moseley, 1877

Dolichoplana striata (Moseley, 1877)

Genus: Microplana   Vejdovsky, 1889
Microplana humicola
(Vejdovsky, 1890) 
Microplana kwiskea Jones, Webster, Littlewood & McDonald, 2008
Microplana scharffi (Graff, 1899) 
Microplana terrestris (Müller OF, 1773)

Genus: Rhynchodemus   Leidy, 1851
Rhynchodemus sylvaticus
(Leidy, 1851)
Somehow, I ended up looking at Terrestial Flatworms (Platyhelminthes) which does include some aquatic species, but this page (and my own interest) ends firmly at the edge of the water. Terrestial (or land) Flatworms are often called Planarians and information about them on the internet is pretty slim.

More about Flatworms

Terrestial Flatworms belong to the Phylum Platyhelminthes, which includes a number of aquatic Flatworms and the parasitic Flukes and Tapeworms. They are smooth and appear glossy, varying in size from 1.0cm upwards depending on species. All become much longer when moving. Flatworms are masters of changing appearance and are one of the UK's real 'shape-shifters' and quite amazing to watch.
Most are small and flattened, often with a ribbon like appearance and covered in a sticky mucus, with an unsegmented body which tapers towards the head. They have no linear gut leading to an anus.

Flatworms leave a thin mucus trail behind them when moving, which can be an indicator to their presence at a site. During movement, the head is held off the floor and sometimes waved around in a snake-like manner. Those species native to the UK (in the Family Rhynchodemidae) all have just two eyes, which are typically difficult to see on dark coloured species, but the number of eyes varies in those harmful species now turning up here after accidental importation.

All Flatworms are hermaphrodite, but perhaps the most incredible ability showed by some species, is the abiklity to multiply by fission Fission is where the animal (or part of it) splits into two, with either section then growing a head or rear end and becoming separate individuals.

The majority of species prey on earthworms, hence the seriousness of importing alien species into the UK.
Marionfyfea adventor (Photograph by Tim Sexton)
Nottinghamshire Flatworm records

There again, even the number of UK records seem few and this time, even J.W. Carr's book 'The Invertebrate Fauna of Nottinghamshire. Nottingham: J.& H. Bell Ltd (1916)' can't provide any help as there were no Nottinghamshire records even then. Carr does have a brief summary of Flatworms, ending with 'Nothing is known in Nottinghamshire of the free living Platyhelminthes, which offer a wide and interesting field for research. It is to be hoped that some local naturalist will take up the study of these animals, which are obviously of much greater importance for faunistic purposes, than the parasitic worms whose life history is so intimately bound up with that of their hosts'.
  Obviously nobody ever read Carr's book, or at least they skipped the Flatworm section and decided to skip straight to Bristletails! But it has to be said, that when you look more closely at Flatworms and do a little research, they do prove extremely interesting and we should take more notice of them, as many species prey on Earthworms and can potentially cause great ecological damage.

As you may have expected by now, records of any Flatworm species in Nottinghamshire are extremely few, in fact just five records and these are all modern day records. Only one record has so far made it on to the NBN Atlas. None of our five county records involve any of the UK's native species.

Marionfyfea adventor
(Jones & Sluys, 2016) originates from New Zealand and is obviously an accidental import to the UK and via the horticultural trade. It is on the Nottinghamshire list through one found by Tim Sexton at Attenborough NR in December 2015. See photograph above right showing this species. There are presently very few UK records.
Australoplana sanguinea (Photograph by Tim Sexton)
Arthurdendyus triangulata (not illustrated) is the New Zealand Flatworm (Dendy, 1895) and is the only Nottinghamshire Flatworm record listed on the NBN Atlas.

The record is from Worksop in 1993 and the four digit grid reference places it somewhere around Priorswell Road, near Worksop Priory and 'The Canch Park '. The record is typically rather vague, as there's no precise date (just 1993) and also no recorder or determiner's name is given.

Australoplana sanguinea
is the Australian Flatworm (Dendy, 1891) and a beautiful orange coloured species. There is just one Nottinghamshire record, from a private garden in Attenborough when found and photographed by Tim Sexton in May 2020.

Australopacifica atrata  (Steel, 1897) is completely black, but grey with a thin dark stripe along it's length ventrally. Another Australian species and a recent arrival to the UK, first appearing in 2015 and with several records since. In September 2020, I came across several of these near the old walled garden at Woodthorpe Park, subsequently finding dozens of them underneath fallen peices of bark on a return visit.
Australopacifica atrata
Rhynchodemus sylvaticus (Leidy, 1851) is a pale brown coloured Flatworm which is thought native to the UK. It is another species recorded by Tim Sexton at Attenborough NR and was recorded in April 2017.

Finding Flatworms in Nottinghamshire

Because non-native Flatworms are arriving here through the horticultural trade, gardens are probably the best place to check for Flatworms. They are usually found in shady and wet places on the soil surface e.g. under flower pots, plant containers, tarpaulins and paving slabs etc.

Because of the potential impact to populations of earthworms and other soil animals, non-native flatworms possess a great risk to both agriculture and horticulture. As such all non-native flatworms are included under Schedule 9 of the 
Wildlife and Countryside Act 1981, which states that it is an offence to introduce or release them into the wild. Additionally, the New Zealand flatworm is included in the Invasive Alien Species of European Union Concern list.

Useful external links: