No abstract

The Icelandic Purple Sandpiper Calidris maritima littoralis (C.L. Brehm, 1831) represents one member of a poorly understood subspecies complex. Currently, differences in size define two other subspecies: Calidris maritima belcheri Engelmoer & Roselaar, 1998, which breeds in north-eastern Canada along the Hudson Bay and James Bay, and Calidris maritima maritima (Brunnich, 1764), which breeds along the Arctic coasts elsewhere in northern Canada, Greenland, Svalbard, Scotland, and Fennoscandia, to northern central Siberia. There are large size differences amongst populations of C. m. maritima, however. As an Arctic/Alpine breeding bird, C. m. littoralis could provide an interesting perspective on the evolutionary changes following a northwards expansion of a species after glacial retreat. Considering the extent of the ice sheet in the northern hemisphere during the last glaciation, and the short period of time since it ended, the correct attribution of subspecies status for C. m. maritima may reflect either rapid diversification from a single population or ancestral splits of distinct evolutionary lineages that survived in isolation at southern latitudes. We applied morphometric subspecies criteria, diagnosability by Amadon's rule, and genetic analysis of five nuclear introns, and the mitochondrial DNA markers cytochrome oxidase c subunit I (COI) and NADH dehydrogenase subunit 2 (ND2), to geographically separate breeding populations in order to examine the subspecies status of the Icelandic population. The results do not provide support for the subspecies status of the Icelandic population because the nominate and Icelandic subspecies fail to uphold Amadon's rule, and genetic analyses indicate that the study populations derive from a single shared refugium.

South America is considered a world biodiversity hotspot, especially for freshwater ecosystems where there is significant biodiversity and endemism across different taxonomic groups. Native South American crayfishes are characterized by small range distributions, high levels of endemism and specific habitat requirements. Although this group may be considered one of the most threatened among South American freshwater crustaceans, IUCN Red List assessments for most of these species are ‘data deficient’. IUCN assessments are technical evaluations of species risk of extinction based on biological indicators of population features, thereby providing a ‘conservation status’ for each species based on common and international standards. Attempts to assess the conservation status of native South American crayfishes have been limited mainly owing to a lack of fundamental data and also misinterpretations of present information. Thus, a revision of the state of knowledge of native South American crayfishes (taxonomy, phylogeny and distribution, genetics, ecology and threats) was carried out coupled with IUCN assessments of conservation status. Globally, the lack of information on the biology of these species is still the major obstacle to making reliable conservation status assessments. For this reason, the Data Deficient (DD) category is still appropriate for many species. However, based on the Extent of Occurrence (EOO) and severely fragmented populations, number of locations and decline in area, extent or quality of habitat, it is recommended that some species (especially Virilastacus spp.) should be moved to threatened categories (VU, EN or CR). The data suggest that others are appropriately in the Near Threatened (NT) category, because they almost reach the thresholds for threatened categories. The assessment of conservation status is essential to support future conservation actions, especially for species allocated to threatened categories. This study has identified new species under threat and also areas for future study to provide relevant data for conservation assessment for ‘data deficient’ species. Copyright © 2014 John Wiley & Sons, Ltd.

The Icelandic subspecies of Eurasian wren Troglodytes troglodytes islandicus has been described as a large wren which is sedentary on the island. It is one member of a large passerine complex which is widely distributed over the Holarctic except the Arctic. The taxonomic affiliation of the subspecies is mainly based on variation in plumage and on the song complexity. This study investigated the genetic differentiation of T. t. islandicus among the Eurasian wren subspecies in northwestern Europe, and especially in relation to its geographically proximate populations in the Faroe Islands, Scotland, southern Norway, Sweden and Denmark. Troglodytes t. islandicus and the Faroese subspecies (T. t. borealis) were genetically differentiated from the other subspecies (T. t. indigenus and T. t. troglodytes) with an estimated time of divergence from this group during the last glacial maximum; 21 thousand years before present (KYBP) [44–8]. A clear but a more recent split was observed between T. t. islandicus and T. t. borealis 12 KYBP [28–4].