An Atlas of Yorkshire Coleoptera
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A Provisional Atlas of the Coleoptera of Yorkshire (Vice Counties 61 –65) Part 1 – Suborder Adephaga: Family Carabidae Introduction There have been 180 years of Coleoptera recording in the historical county of Yorkshire, which includes the vice-counties 61 to 65. The records comprise the YNU Coleoptera database. The purpose of this series of papers is to reassess all our Coleoptera records in the light of modern knowledge of distribution and habitat requirements. The Coleoptera will be covered, it is hoped, in a number of parts. This part will deal with the Carabidae, one of the largest families in terms of species numbers represented in the British fauna. The first authoritative Coleoptera list for the county was begun in 1884 (Nat 1884:??) by Rev WC Hey and continued by ML Thompson in parts. The project to produce a definitive Yorkshire list was continued with the publication of the Victoria County History, within which was a section on the Coleoptera of the County of Yorkshire. There has been nothing since. There have been attempts in the past to review the Yorkshire records, but these have usually tended to deal with the more uncommon taxa, or significant records, or small groups. So-called “common” species have often been neglected in the past, and often not included in the records. I think the main reason for this is that records were added by hand to individual species sheets. Entering a long list of, say, Tachyporus hypnorum, into such a medium must have proven extremely tedious and time-consuming. Therefore it is hardly surprising that recorders only entered significant records. This present work, however, is an attempt to treat all species on an equal footing. Previous reviews and reports include the following – Flint (1988), (Denton 1990, 2003, 2008), Marsh (1991, 2002). Each species in the database is considered and in each case a distribution map representing records on the database (at the end of 2007) 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 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. 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 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 six 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 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, and for this I have drawn heavily on two publications, Luff (1998) and Luff (2007), wherein is much species habitat and frequency information. Taxon status Also given is the accepted national status of each taxon, this being the status as defined in JNCC‟s Recorder 3 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. The following status criteria are derived from Shirt (1987) and Hyman and Parsons (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. 1 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. 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 of records is sufficient to give a meaningful conclusion. 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. Nomenclature The YNU database is presently held in a copy of Recorder 2002, which uses the checklist of Recorder 3, based on Pope (1977). Very recently, a new Coleoptera checklist has emerged (Duff, 2008) and this replaces that of Pope (loc. cit.); the new list incorporates a very large number of taxon name changes. By May 2009, the database will have been upgraded to Recorder 6 and all recording will be done using the new checklist. This report uses the latest checklist as a framework. Occasionally I receive records using “noddy names” (see Cooter, (1999) and Key (1999) for an excellent treatise on 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, confusing and unhelpful. I do not accept records using such names only, unless accompanied by specimens or other convincing evidence. 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 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 requires a grid reference, and with older records I have added a grid reference where I believe this has been possible. If the site name is a vague one I have used a 10km reference, and where a 1km reference is deemed accurate enough I have included that. There can be little excuse with modern records not to include some accurate comment with the record, and at least a six-figure grid reference. Taxonomic knowledge and expertise have increased greatly since the days of Walsh, Bayford and Stainforth. Much good literature now exists for the taxonomist in the form of dichotomous keys, and when identifying specimens, especially with critical species pairs or groups, too much reliance on the outcome of keys can be placed on a determination, without apparently considering the habitat in which the specimen was taken, or the host plant/animal. Atlases of the national distributions of various orders of insect are now becoming available and should always be consulted. These often give a guide to the likelihood or otherwise of a determination, especially in scarce taxa. Museum collections containing correctly determined and labelled specimens are invaluable in accurate recording; museum collections are there for our use and should be consulted. If a species is „new‟ to a vice-county or is very significant in some other respect, a second opinion should always be sought or an acknowledged specialist in the group consulted. A voucher should always be retained by the collector. The recorder can only deal with the information he is given, and often has to beware of identifications made on photographic evidence only, and identifications of „difficult‟ species by non-specialists.