A new species of terrestrial planarian of the genus Microplana (Platyhelminthes Turbellaria; Tricladida: Continenticola) from Yorkshire, United Kingdom; with a discussion of Microplana humicola Vejdovsky 1890 Author Jones, Hugh D. Department of Life Sciences, The Natural History Museum, London SW 7 5 BD. Author Mcdonald, Jillian C. 0000-0002-6441-6705 Bridge House, Kirby Wiske, Thirsk, YO 7 4 ER. jill @ jillmcd. co. uk; https: // orcid. org / 0000 - 0002 - 6441 - 6705 jill@jillmcd.co.uk text Zootaxa 2021 2021-05-31 4980 1 174 184 journal article 6105 10.11646/zootaxa.4980.1.11 ab57e9b9-c446-4db3-81a2-e8744dd2df74 1175-5326 4882858 984CA16F-FA9D-423D-B431-02740688E0B1 Microplana nana Mateos et al ., 1998 , as amended by Vila-Farré et al ., 2011 . Fully stretched living specimens were 8–10 mm long, 0.5 mm wide. Preserved specimens up to 4 mm long x 0.7 mm . The dorsal surface is greyish with darker spots all over the surface; anterior end darker; creeping sole white. The eyes are described as “small ocelli at the anterior end”. Photographs by E. Mateos (pers. comm) of live specimens show that in M. nana the pair of eyes are clearly visible and are each surrounded by a small white patch lacking the dark pigment. Our specimens are slightly smaller and the dark colouration is limited to the anterior rather than the whole length as in M. nana . We were not able to take macro pictures of the eyes of our specimens but the eyes are very small and not superficial, though the anterior end was strongly contracted. Microplana nana has approximately ten pairs of testes. The sperm ducts each expand anterior to the penis and contain stored sperm (false seminal vesicles), enter the base of the penis and discharge separately but close together to form the ejaculatory duct, similar to our specimens. The penis of M. nana is conical but the ejaculatory duct is eccentric, in the ventral half of the penis. The darker pigmentation, larger superficial eyes, and different position of the ejaculatory duct within the penis of M. nana compared to our specimens suggest that they are not of the same species.