The proportion of such undescribed extinct species in collections is unknown, but cases have been demonstrated. Richling and Bouchet (2013), in this issue, cite some examples drawn from different groups of organisms. In addition to species already in collections, historically extinct, but undescribed, species can be discovered from durable remains such as

the hard parts of animals and plants. This is commonplace in palaeontology, but rarely considered for historical extinctions except in the notable case of bird remains on Pacific Islands (Pimm et al. 2006). The case involving snail shells (Richling and Bouchet 2013), shows just how important this can be in some other groups of less well-studied organisms. Implications of extinction before description The occurrence of species that have selleck become

extinct prior to description or see more collection has profound implications for estimates of rates of species extinction. While some of the already-collected but undescribed species, and ones described from newly discovered remains, will still be present living in the wild, others will not. When attempts are made to obtain figures of recorded extinctions so that global estimates of species loss can be made, the issues of undescribed species already in collections and those represented by undiscovered durable remains are generally ignored. It would seem, therefore, that estimates of extinction rates in historical times, which are based on extinctions MCC950 chemical structure of known species (e.g. Dirzo and Raven 2003), will necessarily be underestimates. Biodiversity and Conservation is not a taxonomic journal, and the current policy is not to accept submissions that include new species descriptions. However, following discussion between the Publishers and ourselves (as Editor-in-Chief and Corresponding Editor, respectively), an exception is made here for the paper of Richling and Bouchet (2013). This unusual step has been taken as that mafosfamide paper

serves to emphasise, to all conservation biologists and biodiversity scientists, that recorded historical species extinctions will always underestimate the true situation in diverse groups of organisms. It also implicitly emphasizes the key role of and need for detailed taxonomic study (Sluys 2013), especially of lesser known groups (Ponder and Lunney 1999), as the foundation for comprehensive biodiversity conservation. If there are indeed sufficient numbers of taxonomists worldwide to cope with the task of describing all eukaryote species on Earth as Costello et al. (2013) argue, it is evident that efforts need to be re-directed towards the least known groups, notably fungi, invertebrates and protists.