Role of the Dinaric Karst (western Balkans) in shaping the phylogeographic structure of the threatened crayfish Austropotamobius torrentium

1. This study examines phylogeography and phylogeny of the threatened stone crayfish, Austropotamobius torrentium, in order to elucidate the role of the Dinaric Karst geology in shaping the evolutionary history and genetic diversity of aquatic fauna in the western Balkans. Mitochondrial 16S rRNA and COI genes were partially sequenced from 188 and 159 crayfish, respectively, sampled from 70 localities. Phylogenetic relationships were reconstructed using four methods of phylogenetic inference. Divergence times between phylogroups were estimated in a Bayesian framework, and their demographic history was examined using neutrality tests and mismatch distribution analysis. 2. Seven geographically localised phylogroups separated by pronounced genetic gaps were found. Five of them have a distribution range within the northern‐central Dinaric (NCD) region, while the remaining two include populations from the southern Balkans (SB) and central and south‐eastern Europe (CSE). The oldest divergence event separated two NCD lineages from the rest of populations in the Late Miocene or Early Pliocene. Divergences amongst the five NCD phylogroups and SB + CSE occurred in the Pliocene. The most recent split separated SB and CSE phylogroups during the Late Pliocene. For both genes, uncorrected pairwise divergences between most of the phylogroups (4.1–8.7% for COI and 1.6–4.8% for 16S rRNA) were of the same range as, or higher than, some of the interspecific distances previously reported for the genus Austropotamobius. 3. Geographically isolated and deeply divergent cryptic monophyletic phylogroups within A. torrentium in the NCD region arose in the course of intensification of Neotectonic movements during the Pliocene and the beginning of the Pleistocene and the development of karstification that has heavily fragmented the palaeohydrography of the area. The results confirm a gradual north–south expansion of stone crayfish during the pre‐Pleistocene that preceded the rapid northward post‐glacial re/colonisation of central Europe (CSE phylogroup) through the Danube drainage. 4. Austropotamobius torrentium comprises morphologically cryptic but molecularly distinct taxa. Considering the relatively small geographical areas they inhabit, the NCD phylogroups of stone crayfish should be given the highest conservation priority.     

The development of eight microsatellite loci in the wild daffodil Narcissus triandrus (Amaryllidaceae)

We report microsatellite primer pairs for the wild tristylous daffodil, Narcissus triandrus (Amaryllidaceae). From enriched libraries, we identified 58 unique microsatellite loci. We designed primer pairs for 27 of these loci and screened genomic DNA from 38 to 40 adults from a single population. For eight polymorphic loci, the number of alleles per locus ranged from five to 17. As six primers also amplified loci in three other Narcissus species, including two horticultural varieties, we expect that some of these markers will be transferable to other Narcissus species.     

Low population differentiation and high genetic diversity in the invasive species Carduus acanthoides L. (Asteraceae) within its native range in the Czech Republic

Colonizing species are predicted to suffer from reductions in genetic diversity during founding events. Although there is no unique mode of reproduction that is characteristic of successful plant colonizers, many of them are predominantly self-fertilizing or apomictic species, and almost all outcrossing colonizers are self-compatible. Carduus acanthoides comprises a species of disturbed habitats with wind-dispersed seeds that colonizes open spaces of various sizes. Population genetic diversity was expressed by assessing patterns of variation at nine putatively neutral allozyme loci within and among 20 natural populations in its native distribution range in the Czech Republic. Overall, C. acanthoides displayed high levels of genetic diversity compared to other herbaceous plants. The percentage of polymorphic loci was 84.5, with values of 2.37, 0.330, and 0.364 for the mean number of alleles per polymorphic locus ( A ), observed heterozygosity ( H _o), and expected heterozygosity ( H _e), respectively. There was only weak evidence of inbreeding within populations ( f  = 0.097) and very low genetic differentiation among populations ( θ  = 0.085). Analyses of the data provide strong evidence for isolation-by-distance for the whole study area. Even the colonizing species, C. acanthoides , currently supports a substantial amount of allozyme variation at both the species and population levels.  © 2009 The Linnean Society of London, Biological Journal of the Linnean Society , 2009, 98 , 596–607.     

Immigration and in situ glacial survival of the low-alpine Erinus alpinus (Scrophulariaceae)

It has been hypothesized that the subalpine Erinus alpinus survived the Pleistocene glaciation in southern French refugia peripheral to the Alps and postglacially immigrated to its northern Alpine distribution (tabula rasa hypothesis). However, E. alpinus is also known from nunataks in the northern Prealps. PCR–RFLP of the cpDNA revealed no variation, whereas AFLPs identified three phylogeographical groups among the 22 populations: (1) a central Swiss group, (2) a single central Swiss population on Mount Rigi, and (3) all other populations located to the west and east of the central Swiss group (west-eastern populations). The population representing the putative French refugium was not distinct from the west-eastern populations but was different from the populations of central Switzerland. We consider this support for locally restricted in situ survival of E. alpinus in the northern Prealps or nearby Jura mountains (dating back to 60–28 ky BP). However, the west-eastern gene-pool probably immigrated postglacially from southern France through the prealpine lowlands (not before 14.6 kyr BP), skirting central Switzerland. The near-absence of gene flow among the central Swiss and the west-eastern populations may be the reason why these historical genetic patterns are still detectable.  © 2002 The Linnean Society of London, Biological Journal of the Linnean Society , 2002, 77, 87–103.     

Morphological and allozyme diversity in the Hieracium nigrescens group (Compositae) in the Sudety Mountains and the Western Carpathians

The overall pattern of morphological variation and genetic diversity (allozyme analysis) was studied in the Hieracium nigrescens group (H. nigrescens s.l., H. alpinum ≥ H. murorum) in the Sudety Mountains and the Western Carpathians. A morphological analysis was performed on 180 plants from 12 populations belonging to six a priori distinguished taxa. Altogether, 25 characters were measured or scored. Morphometric (canonical discriminant analysis) data separated five taxa, evaluated here at the species rank: H. chrysostyloides, H. decipiens, H. nigrescens (all from the Sudety Mountains), H. jarzabczynum, and H. vapenicanum (the Western Carpathians). A distinct local population from Mount Babia hora (the Western Carpathians) comprised a further possible taxon, given the preliminary name ‘H. babiagorense’. Genetic diversity was studied in 17 populations of H. chrysostyloides, H. decipiens, H. jarzabczynum, H. nigrescens, H. vapenicanum and ‘H. babiagorense’ using five enzyme systems. All a priori recognized species were proved to be genetically homogeneous, each consisting of one unique multilocus allozyme genotype, except ‘H. babiagorense’ which shared the same genotype with H. jarzabczynum. For the first time, a chromosome number is reported for H. vapenicanum (2n = 3x = 27) and previously published numbers were confirmed for H. chrysostyloides (2n = 5x = 45), H. decipiens (2n = 4x = 36), H. jarzabczynum (2n = 4x = 36), H. koprovanum (2n = 4x = 36), and H. nigrescens (2n = 4x = 36). All species have been shown to be endemic to either the Sudety Mountains or the Western Carpathians. Except for the species studied, two further ones (H. apiculatum, H. nivimontis) are recognized in the area, giving a total of seven species from the Hieracium nigrescens group in the area studied. The morphologically slightly different local population from Mount Babia hora/Babia Góra (‘H. babiagorense’) requires further study. Two new combinations are proposed: Hieracium jarzabczynum (Paw?. & Zahn) Mráz & Chrtek f. and Hieracium vapenicanum (Lengyel & Zahn) Chrtek f. & Mráz. © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society, 2007, 153 , 287–300.     

Reproductive biology, variability of nectar features and pollination of Combretum fruticosum (Combretaceae) in Argentina

Flower morphology, nectary structure, nectar features (chemical composition, secretion pattern, standing crop, removal effects) and flower visitors are analysed in an Argentinian population of Combretum fruticosum. The variability of these data was examined throughout the flower lifetime. Nectar is hexose dominant. Its chemical composition and concentration are constant for all flowering stageS. Nectar volume varies as a function of flower age due to a combination of nectar secretion, cessation and resorption periods. The overall sugar production is decreased by nectar removal. The plant is self-incompatible and xenogamouS. Only 16.2% of the flowers set seedS. Inflorescences with green flowers were exclusively visited by two hummingbird and three perching bird species which transfer the pollen. A clear link was observed among nectar production pattern, standing crop of nectar, and visitors' behaviour.     

Chromosomes of two species of Tisbe (Copepoda, Harpacticoida) belonging to different groups of sibling species

Karyological investigations curried out on Tisbe marmorata and T. dobzhanskii confirmed the diploid value 2 n = 24 for the former species; on the basis of more than 200 observations it was ascertained that the diploid number of the latter species corresponds to 22, in contrast with a previous report. The karyotypes of these two species differ both in morphology and in location of satellites, not only from each other, but also from all other species so far examined. A close comparison of the two species with their respective siblings is made.