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Atlas of Yorkshire Coleoptera part 6 - Scarabaeoidea (Geotrupidae, Trogidae, Lucanidae and Scarabaeidae) Introduction This is Part 6 of the Atlas and covers the Scarabaeoidea, to include the Lucanidae, Trogidae, Bolboceratidae, Geotrupidae, and Scarabiidae. 101 species of Scarabaeoidea are known from Britain, of the roughly 35000 or so described worldwide taxa. Many species are fossorial and habitats range from dung and plant roots in the Scarabaeidae and Geotrupidae, rotting wood in the case of the Lucanidae , and carrion and dung in Trogidae. Please refer to the work of Freude, Harde and Lohse 8:266ff for the mid-European species, this publication covering most of the British species, and also the works of Jessop (1986), Britton (1956) and Joy (1932) for habitat requirements and distributions of the British species, although Britton and Joy are now much out of date. The Scarabaeoidea is a rather poorly worked group in Yorkshire, and many species appear to be very scarce, especially of Aphodius, owing to the lack of fieldwork, with no records received for many species for many years. Each species in the database is considered and in each case a distribution map representing records on the database (at April 2016) is presented. The number of records on the database for each species is given in the account in the form (a,b,c,d,e) where a to e are the number of records from VC61 to VC65 respectively. These figures include undated records (see comment on undated records in the paragraph below on mapping). As a recorder, I shall continue to use the vice-county recording system, as the county is thereby divided up into manageable, roughly equal, areas for recording purposes. For an explanation of the vice-county recording system, under a system devised in Watson (1883) and subsequently documented by Dandy (1969), Britain was divided into convenient recording areas ("vice- counties"). Thus Yorkshire was divided into vice-counties numbered 61 to 65 inclusive, and notwithstanding fairly recent county boundary reorganisations and changes, the vice-county system remains a constant and convenient one for recording purposes; in the text, reference to “Yorkshire” implies VC61 to VC65 ignoring modern boundary changes. For some species there are many records, and for others only one or two. In cases where there are five species or less full details of the known records are given. Many common species have quite a high proportion of recent records. This is because the older county recorders tended not to record species they regarded as "common" quite as assiduously as we do today. “Recent” records are those considered to be later than 1 January 1990 – this is also the break point used in the production of the distribution maps. Habitat A brief statement on habitat is included where known and relevant. Taxon status The national status of each taxon is given, this being the status as defined in JNCC’s Recorder6 data program. Status is included if Notable B or above. Please bear in mind that many of these statuses are now in need of revision, in the light of recent knowledge of distribution and frequency. The following status criteria are derived from Shirt (1987) and Hyman and Parsons (1992 and 1994): RED DATA BOOK CATEGORY 1. RDB1 – ENDANGERED - Species which are known or believed to occur only as a single population within one 10km square of the OS National Grid. RED DATA BOOK CATEGORY 2. RDB2 – VULNERABLE - Species which are declining throughout their range. RED DATA BOOK CATEGORY 3. RDB3 – RARE - Species which are estimated to exist in only 15 or fewer 10km squares; this criterion may be relaxed where populations are likely to exist in more than 15 squares but occupy small areas of especially vulnerable habitat. RED DATA BOOK CATEGORY I. RDB I – INDETERMINATE - Taxa considered to be endangered, Vulnerable or Rare, but where there is not enough information to say which of the three categories (RDB1 to 3) is appropriate. RED DATA BOOK CATEGORY K. RDBK – INSUFFICIENTLY KNOWN - Taxa recently discovered or recognised in Great Britain, which may prove to be more widespread in the future (although some recent discoveries may be placed in other categories if the group to which they belong is thought to be not under-recorded). PROVISIONAL RED DATA BOOK. Prdb - The prefix ‘p’ before any red Data Book category implies that the grading is provisional. Notable A – species which do not fall within the RDB categories but are thought to occur in 30 or fewer 10km squares of the National Grid, or for less well-recorded groups, within seven or fewer vice-counties. Notable B – species which do not fall within the RDB categories but thought to occur in between 31 and 100 10km squares of the National Grid. 1 | P a g e Nationally Notable - species which are estimated to occur within the range of 16 to 100 10km squares. (subdivision into Notable A and Notable B is not always possible because there may be insufficient information available). Now generally superseded by Nationally Scarce, and therefore no longer much used in modern literature. The following status criteria are included in the species accounts and derive from those used in the Recorder 6 database. Please note that many of these statuses require reconsideration in the light of currently known records and distributions. RedList_pre94-EN - Taxa in danger of extinction and whose survival is unlikely if the causal factors continue operating.. Superseded by new IUCN categories in 1994, so no longer in general use. RedList_pre94-EX - Taxa which are no longer known to exist in the wild after repeated searches of their localities and other known likely places. Superseded by new IUCN categories in 1994, so no longer in general use. RedList_pre94-NR - Taxa with small populations that are not at present Endangered or Vulnerable, but are at risk. (In GB, this was interpreted as species which exist in fifteen or fewer 10km squares). Superseded by new IUCN categories in 1994, so no longer in general use. HabDir-A2* - Animal and plant species of Community interest (i.e. endangered, vulnerable, rare or endemic in the European Community) whose conservation requires the designation of special areas of conservation. Note that the contents of this annex have been updated in April 2003 following the Treaty of Accession. A revised set of criteria governing taxon status is to be published shortly (DMa pers comm. to RJM), but for the time being the existing taxon status criteria and definitions included in the latest version of Recorder 6 will be used here. Phenology Details are given for the range of months in the year for which there are records, with or without a peak month of occurrence, where the number and detail of records are sufficient to give a meaningful statement. Maps Distribution maps have been produced using Dr Alan Morton’s DMAP software (version 7.0b). It may be worthwhile to note that as DMAP is asked to map pre- and post-1990 records in this application, any undated records will not be mapped. While efforts have been made to establish dates of records, some are difficult to ascertain, and I do not want to make guesses which may be wrong. Nomenclature The YNU database is presently held in a copy of Recorder 6, which uses a new Coleoptera checklist (Duff, 2008) and this new list incorporates a very large number of taxon name changes since the checklist of Pope (1977); there is now a second edition of the latest Coleoptera checklist (Duff, 2012) which has not yet been incorporated into Recorder 6. Occasionally I receive records using “noddy names” (see Cooter, (1999) and Key (1999) for an excellent treatment of this subject), e.g. “Snail Hunter”, “Crucifix Beetle” and “Heath-glory ground beetle” (Cychrus caraboides, Panagaeus crux-major and Carabus nitens respectively). Such inventions were designed for use in political documents, and seem to have originated somewhere within Natural England (previously English Nature) or JNCC. For the purposes of serious science these terms are, in my opinion, vague, ridiculous, confusing and unhelpful. I do not accept records using such names only, unless accompanied by specimens or other convincing evidence. The arrangement of species in the Atlas follows that of the latest Duff (2012) Checklist. There is however a new checklist of the Scarabaeidae shortly to be published by Darren Mann. Included in this all subgenera of Aphodius will be raised to generic rank. In the meantime for the purposes of this atlas the existing Duff 2012 checklist will be used. Quality of the records A regrettable aspect of some of the records within the YNU database in particular (and I suspect sometimes within entomological datasets in general) is the lack of attention to detail accompanying the record, especially of accurate grid references, lack of pertinent comments as to the micro-habitat of the capture, its association with plants/animals, and sometimes, in the case of some modern records, a lack of care in determination, and the recording of the sex of the specimen. Old records, although sound, tend not to give much or indeed any of this detail. Old records on the database so rarely give habitat details but sometimes interpretation of the site name can give clues to the habitat type. Grid references could not be applied before 1930 anyway, and grid references do not figure in the paper archive of the YNU Coleoptera database until the late 1970s. Apparently it was not considered necessary to give that level of accuracy. Entering records onto Recorder 6 requires a grid reference, and with older records I have added a grid reference where I believe this has been possible.