Abstract
Terrestrial planarians with a dorsal yellow stripe and dark lateral surfaces and up to 15-20 cm long have been found in several countries in Europe, the earliest in 2008. They are similar to two species originally from Australia, Caenoplana variegata (Fletcher & Hamilton, 1888) and C. bicolor (Graff, 1899), both described on external characters only, with no anatomical information. Careful reading suggests that there is no significant difference between the original descriptions. Further: observations on live specimens show considerable variation between individuals and in individuals over time and before and after feeding, negating any distinction between descriptions. Examination of three sectioned specimens shows considerable difference in sexual maturity, though one seems almost fully mature and the reproductive system is described. Molecular results show that specimens from the United Kingdom and Spain are of the same species. It is concluded that the planarians should be referred to as C. variegata, C. bicolor being a junior synonym.
References
Álvarez-Presas, M., Carbayo, F., Rozas, J., & Riutort, M. (2011) Land planarians (Platyhelminthes) as a model organism for fine-scale phylogeographic studies: understanding patterns of biodiversity in the Brazilian Atlantic Forest hotspot. Journal of Evolutionary Biology, 24 (4), 887–896.
https://doi.org/10.1111/j.1420-9101.2010.02220.x
Álvarez-Presas, M., Mateos, E., Tudó, À., Jones, H.D. & Riutort, M. (2014) Diversity of introduced terrestrial flatworms in the Iberian Peninsula: a cautionary tale. PeerJ, 2 (e430), 1–35.
https://doi.org/10.7717/peerj.430
Brittlebank, C.C. (1888) Food of planarians. The Victorian Naturalist, 5, 48.
Carranza, S., Littlewood, D.T.J., Clough, K.A., Ruiz-Trillo, I., Baguñà, J. & Riutort, M. (1998) A robust molecular phylogeny of the Tricladida (Platyhelminthes: Seriata) with a discussion on morphological synapomorphies. Proceedings of the Royal Society of London, Series B, 265, 631–640.
https://doi.org/10.1098/rspb.1998.0341
Darriba, D., Taboada, G.L., Doallo, R. & Posada, D. (2012) jModelTest 2: more models, new heuristics and parallel computing. Nature Methods, 9 (8), 772.
https://doi.org/10.1038/nmeth.2109
Dendy, A. (1892) Descriptions of some land planarians from Queensland. Proceedings of the Royal Society of Victoria, 4, 123–129.
Dendy, A. (1893) Notes on some new or little-known Land Planarians from Tasmania and South Australia. Proceedings of the Royal Society of Victoria, 6, 178–188.
Dendy, A. (1893) Further notes on the land planarians of Tasmania and South Australia. Australasian Association for the Advancement of Science, Adelaide, SA, 5, 420–423.
Dendy, A. (1894) Notes on some land planarians collected by Thos. Steel, Esq., F.C.S., in the Blue Mountains, N.S.W. Proceedings of the Linnean Society of New South Wales, 9, 729–734.
https://doi.org/10.5962/bhl.part.18142
Fletcher, J.J. & Hamilton, A.G. (1888) Notes on Australian land-planarians, with descriptions of some new species. Proceedings of the Linnean Society of New South Wales, 2, 349–374.
https://doi.org/10.5962/bhl.part.29186
Graff, L. von (1896) Über die Morphologie des Geschlechtsapparates der Landplanarien. Verhandlungen der Deutschen Zoologischen Gesellschaft, 6, 75–93.
Graff, L. von (1899) Monographie der Turbellarien. II. Tricladia Terricola (Landplanarien). W. Engelmann, Leipzig, 574 pp., atlas, taf. I–LVIII.
Hall, T.A. (1999) BioEdit: a user-friendly biological sequence alignment editor and analysis program for Windows 95/98/NT. Nucleic Acids Symposium Series, 41, 95–98.
Justine, J-L. Thévenot, J. & Winsor, L.W. (2014) Les sept plathelminthes invasifs introduits en France. Phytoma, No 674, 28–32.
Lang, A. (1884) Die Polycladen (Seeplanarien) des Golfes von Neapel und der angrenzenden Meeresabschnitte. Eine Monographie. Fauna und Flora des Golfes von Neapel, 11, Verlag von Wilhelm Engelmann, Leipzig, IX + 688 pp., 39 pls.
https://doi.org/10.5962/bhl.title.10545
Lázaro, E.M., Sluys, R., Pala, M., Stocchino, G.A., Baguñà, J. & Riutort, M. (2009) Molecular barcoding and phylogeography of sexual and asexual freshwater planarians of the genus Dugesia in the Western Mediterranean (Platyhelminthes, Tricladida, Dugesiidae). Molecular Phylogenetics and Evolution, 52 (3), 835–845.
https://doi.org/10.1016/j.ympev.2009.04.022
Miller, M.A., Pfeiffer, W. & Schwartz, T. (2010) Creating the CIPRES Science Gateway for Inference of Large Phylogenetic Trees. In: Proceedings of the Gateway Computing Environments Workshop (GCE), New Orleans, LA, 2010, pp. 1–8.
https://doi.org/10.1109/GCE.2010.5676129
Moseley, H.N. (1877) Notes on the structure of several forms of land planarians, with a description of two new genera and several new species, and a list of all species at present known. Quarterly Journal of Microscopical Science, 17, 273–292.
Nguyen, L.T., Schmidt, H.A., Von Haeseler, A. & Minh, B.Q. (2015) IQ-TREE: A fast and effective stochastic algorithm for estimating maximum-likelihood phylogenies. Molecular Biology and Evolution, 32 (1), 268–274.
https://doi.org/10.1093/molbev/msu300
Ogren, R.E. & Kawakatsu, M. (1991) Index to the species of the family Geoplanidae (Turbellaria, Tricladida, Terricola) Part II: Caenoplaninae and Pelmatoplaninae. Bulletin of the Fuji Women’s College, No. 29, Series II, 25–102.
Puillandre, N., Lambert, A., Brouillet, S. & Achaz, G. (2012) ABGD, Automatic Barcode Gap Discovery for primary species delimitation. Molecular Ecology, 21 (8), 1864–1877.
https://doi.org/10.1111/j.1365-294X.2011.05239.x
Ronquist, F., Teslenko, M., van der Mark, P., Ayres, D.L., Darling, A., Höhna, S., Larget,B., Liu, L., Suchard, M.A. & Huelsenbeck, J.P. (2012) MrBayes 3.2: Efficient Bayesian phylogenetic inference and model choice across a large model space. Systematic Biology, 61 (3), 539–542.
https://doi.org/10.1093/sysbio/sys029
Sluys R. (2016) Invasion of the flatworms. American Scientist, 104, 288–295.
https://doi.org/10.1511/2016.122.288
Steel, T. (1900) Tasmanian land planarians. Proceedings of the Linnean Society of New South Wales, 25, 618–631.
https://doi.org/10.5962/bhl.part.12179
Stimpson, W. (1857) Prodromus descriptiones animalium evertebratum quae in Expeditione ad Oceanum Pacificum Septentrionalem a Republica Federata missa, Johnne Rodgers Duce, observavit et descripsit. Proceedings of the Academy of Natural Sciences, Philadelphia, 9, 19–31.
https://doi.org/10.5962/bhl.title.51447
Vardinoyannis, K. & Alexandrakis, G. (2019) First record of the land planarian Caenoplana bicolor (Graff, 1899) (Platyhelminthes, Tricladida, Continenticola) in Greece. BioInvasions Records, 8 (3), 500–504.
https://doi.org/10.3391/bir.2019.8.3.04
Waart, S. de (2016) Exotische landplatwormen in Nederland (Platyhelminthes: Tricladida). Nederlandse Faunistische Mededelingen, 47, 1–10.
Winsor, L.W. (1973) Geoplana varigata Fletcher & Hamilton 1887—A new land planarian record for Victoria. The Victorian Naturalist, 90, 264–265.
Winsor, L.W. (1977) Terrestrial planarians and nemerteans of the Otway Region. Proceedings of the Royal Society of Victoria, 89, 137–146.
Winsor, L.W. (1991) A provisional classification of Australian terrestrial geoplanid flatworms (Tricladida: Terricola: Geoplanidae). The Victorian Naturalist, 108, 42–49.
Winsor, L.W. (1997) The biodiversity of terrestrial flatworms (Tricladida; Terricola; Terricola) in Queensland: a preliminary report. Memoirs of the Museum of Victoria, 56 (2), 575–579.
https://doi.org/10.24199/j.mmv.1997.56.52
Zhang, J., Kapli, P., Pavlidis, P. & Stamatakis, A. (2013) A general species delimitation method with applications to phylogenetic placements. Bioinformatics, 29 (22), 2869–2876.
https://doi.org/10.1093/bioinformatics/btt499