This account of Collembola builds on that in the first edition of the Red Data Book (Turk in Spalding (Ed.), 1997) Of just over 300 British species listed by Kloet & Hincks (1964), Marquand (1881; 1884) recorded 44 in Cornwall, and there was no further recording until some unpublished lists were made by Dr F.A. Turk in the 1940s. None are more than 5mm long, and they rarely attract attention unless they are swarming or unless they are the few species that affect such crops as mushrooms and seedlings, especially in glasshouses. All need a high degree of moisture, and several occur on or near water; some live on the shore and one is able to withstand immersion by the tide. Recording improved when the national recorder of Collembola, Dr. Steven Hopkin, made a study of and recorded Springtails in the years he spent in Cornwall up to 2006. His research was cut short when he was tragically killed in a car accident that year. The following list of species is from his website which is still available online www.stevehopkin.co.uk/collembolamaps/. In the introduction to Collembola Maps on the website, Dr. Hopkin noted that “the checklist below [of species on the full list] includes changes arising from recent taxonomic decisions, new synonyms, and the discovery of several misidentifications in the NHML Collembola collections. Several ‘species’ are undoubtedly complexes of two or more species. However, I have decided to adopt a conservative approach until fresh UK/Eire material can be examined to resolve some of the more contentious species boundaries”. The records mapped on the website were confirmed by Dr. Hopkin from examination of microscope slides in the Natural History Museum, London (NHML), specimens in his reference collection, or material sent to him by recorders. He also included all accepted published records. The national recorder for Collembola is now Dr. Peter Shaw of Roehampton University, who has transcribed the Collembola information from Dr. Hopkin’s website, and this is now hosted by the University’s Centre for Research in Ecology and maintained by Dr. Shaw - see www.roehampton.ac.uk/collembola/. For a small and under-recorded group no Red Data Book has been produced, but Dr. Hopkin put forward a provisional status for this under-recorded group, and even those that he thought were very common were only recorded at a level of more than 50 hectads in the UK and Eire. Common species were present in 26 to 50 hectads, moderately common present in 11 to 25 hectads, scarce present in six to 10 hectads and rare present in five or fewer hectads. Due to the limited number of records, the following is a brief summary of those species of Collembola that Dr. Hopkin thought moderately common to rare nationally. The following list is ordered taxonomically (as found on the website) and includes some abridged notes from Dr. Hopkin’s descriptions. Dates are given where known. The numbers of how many 10 x 10 kilometre squares the species are found in Cornwall are after the national status. Many thanks to Ailsa Hopkin for permission to use the information, and to Peter Shaw for advice.