Feeding range studies of Rodolia cardinalis (Mulsant), a candidate biological control agent of Icerya purchasi Maskell in the Galápagos islands

The immediate threat of the cottony cushion scale, Icerya purchasi Maskell (Homoptera: Margarodidae), to the conservation of endangered flora in the Galápagos islands prompted conservation groups to assess the risks associated with the introduction of its natural enemy, Rodolia cardinalis (Mulsant) (Coleoptera: Coccinellidae). Although R. cardinalis has been widely used for controlling this exotic pest, little information was found to confirm its presumed narrow feeding range. Consequently, studies were deemed necessary to determine whether the introduction of R. cardinalis would harm the island’s native invertebrate fauna, in particular rare or threatened species. Using no-choice trials, we tested neonate and third instar larvae of R. cardinalis against 16 and 11 potential prey species, respectively. Adults with prior feeding experience on I. purchasi were tested against eight non-target species and naïve adults (those that had not fed on I. purchasi) were tested against six. These trials included up to 35% of the Homoptera species of conservation value presumed to have the highest risk of being preyed upon by R. cardinalis. To maximize the range of species exposed to R. cardinalis, feeding trials were also carried out with some introduced species representative of groups containing potential non-target species that were not located for testing. R. cardinalis was unable to complete its life cycle on any of the test prey species and only fed on Margarodes similis Morrison (Homoptera: Margarodidae), a species closely related to the cottony cushion scale. M. similis, however, is subterranean and in its natural habitat is not at risk from foraging by R. cardinalis. Based on these trials, we believe that immature stages of R. cardinalis will have no impact on the non-target invertebrate fauna of the Galápagos islands because they specialize on Margarodidae. Although the limited nature of our testing prevents us from reaching a definitive conclusion about the prey range of R. cardinalis adults, our results indicate that it is also narrow. According to our field and laboratory studies, niche overlap with native predators of Homoptera will be minimal and intraguild predation should not occur.     

A comparison of genetic diversity between the Galápagos Penguin and the Magellanic Penguin

The Galápagos Penguin (Spheniscusmendiculus) is a United States federallylisted endangered species with populations onthe Galápagos Islands of Fernandina andIsabela. Although the waters around theislands are normally productive, lowproductivity during El Niño years resultsin high adult penguin mortality and lowrecruitment in following years. We usedmicrosatellite markers developed for Spheniscus penguins to study the long termgenetic effects of serial bottleneck events inthe Galápagos Penguin, and compared thisvariation to that of its congener, theMagellanic penguin (Spheniscusmagellanicus). The observed heterozygosityfor the Galápagos Penguin was 3%,significantly lower than the 46%heterozygosity of the Magellanic Penguin. Thislow level of heterozygosity is directly relatedto its low effective population size. Whilethis population has survived long term,presumably without high levels of geneticvariation, we feel that the greater frequencyof El Niño events, coupled with increasedhuman impacts such as introduced disease, oildischarge, and competition with fisheries, mayput the species in particular danger ofextinction.     

Are the preference and selection patterns of hermit crabs for gastropod shells species- or site-specific?

Experimental analyses of hermit crabs and their preferences for shells are essential to understand the intrinsic relationship of the crabs' dependence on shells, and may be useful to explain their shell use pattern in nature. The aim of this study was to evaluate the effect of crab species and site on the pattern of shell use, selection, and preference in the south-western Atlantic hermit crabs Pagurus brevidactylus and Pagurus criniticornis, comparing sympatric and allopatric populations. Differently from the traditional approach to evaluate shell preference by simply determining the shell selection pattern (i.e., the number of shells of each type selected), preference was defined (according to [Liszka, D., Underwood, A.J., 1990. An experimental design to determine preferences for gastropod shells by a hermit-crab. J. Exp. Mar. Biol. Ecol., 137(1), 47–62]) by the comparison of the number of crabs changing for a particular shell type when three options were given (Cerithium atratum, Morula nodulosa, and Tegula viridula) with the number of crabs changing for this same type when only this type was offered. The effect of crab species was tested at Cabelo Gordo Beach, where P. brevidactylus was found occupying shells of C. atratum, M. nodulosa, and T. viridula in similar frequencies, whereas P. criniticornis occupied predominantly shells of C. atratum. In laboratory experiments the selection patterns of the two hermit-crab species for these three gastropods were different, with P. criniticornis selecting mainly shells of C. atratum, and P. brevidactylus selecting more shells of M. nodulosa. The shell preference was also dependent on crab species, with P. criniticornis showing a clear preference for shells of C. atratum, whereas P. brevidactylus did not show a preference for any of the tested shells. The effect of site was tested for the two species comparing data from Cabelo Gordo to Preta (P. brevidactylus) and Araçá beaches (P. criniticornis). The pattern of shell use, selection, and preference was demonstrated to be dependent on site only for P. brevidactylus. The results also showed that the shell use pattern of P. criniticornis can be explained by its preference at both sites, whereas for P. brevidactylus it occurred only at Cabelo Gordo, where the absence of preference was correlated with the similar use of the three gastropod species studied. Finally, the results showed that the shell selection pattern cannot be considered as a measure of shell preference, since it overestimates crab selectivity.     

Stand-level dieback and regeneration of forests in the Galápagos Islands

Stand-level dieback and regeneration of forests in Galápagos are discussed, and related to natural- and man-made disturbances. The dieback of Scalesia pedunculata (Asteraceae) in Galápagos seems to follow the etiology and patterns seen in other pacific island groups. The currently large and synchronized cohorts of this early-successional species, found on Santa Cruz Island, may be explained by severe disturbances such as the natural el Niño phenomenon and human caused fires. It is suggested, that slow-growing species such as Zanthoxylum fagara, Psidium galapageium and Acnistus ellipticus have been suppressed by frequent fires in the highlands of Santa Cruz. The population dynamics of Scalesia pedunculata are suggested to follow a cyclus of 10–20 years duration, caused by senescence in the Scalesia stand, and promoted by extreme stress. Stand-level dieback is also reported from Scalesia cordata, Erythrina velutina and Miconia robinsoniana.     

Parasitoids associated with the common pistachio psylla, Agonoscena pistaciae, in Iran

The parasitoids associated with the common pistachio psylla, Agonoscena pistaciae Burckhardt and Lauterer, were investigated at three pistachio plantations in Rafsanjan, Iran. Of the 6504 wasps emerging from mummified psyllids, 46% were the primary parasitoid Psyllaephagus pistaciae Ferrière, and the remaining 54% represented six species of hymenopterous hyperparasitoids, including Chartocerus kurdjumovi (Nikol’skaja), Marietta picta (André), Pachyneuron aphidis (Bouché), Pachyneuron muscarum (Linnaeus), Psyllaphycus diaphorinae (Hayat), and Syrphophagus aphidivorus (Mayr). Lysiphlebus fabarum Marshall, the parasitoid of Aphis gossypii Glover and Aphis craccivora Koch present on weeds, was found to be an alternative host for three major hyperparasitoids of A. pistaciae. The most abundant hyperparasitoid was S. aphidivorus, appearing during the growing season in all trial locations on psyllids and aphids in pistachio orchards. The weed-infesting aphids, along with their primary parasitoid, can act as a reservoir of A. pistaciae secondary parasitoids. Therefore, parasitized aphids allow populations of secondary parasitoids to increase and consequently to apply higher pressure on P. pistaciae. We detected that two primary parasitoid species, including P. pistaciae and L. fabarum, attacking different species of hosts interact indirectly through shared secondary parasitism. It is suggested that the community structure of A. pistaciae may be influenced by apparent competition, although more work is needed to provide firm evidence.     

Negative dietary effects of Colorado potato beetle eggs for the larvae of native and introduced ladybird beetles

Aphidophagous ladybird beetles (Coleoptera: Coccinellidae) are attracted to and feed heavily on aphids, but many species will also feed opportunistically on other prey that they encounter. In potatoes (Solanum tuberosum L.) in Washington State, USA, coccinellids feed on both green peach aphids (“GPA,” Myzus persicae Sulzer) and eggs of the Colorado potato beetle (“CPB,” Leptinotarsa decemlineata Say). The guild of aphidophagous ladybirds includes two native species, Hippodamia convergens Guérin-Méneville and Coccinella transversoguttata Brown. Recently, an introduced species, Coccinella septempunctata L., has invaded and apparently displaced its native congener. A second exotic, Harmonia axyridis Pallas, has colonized the area and is becoming more abundant. We compared larval development of each species on a monotypic diet of GPA, a monotypic diet of CPB eggs, or a mixed diet of both GPA and CPB eggs. Our goal was to answer two questions: (1) do larvae of the four ladybird species benefit from including CPB eggs in their diet and (2) do the four ladybird species differ in their ability to utilize CPB eggs as prey? No larva of any species completed development on a pure diet of CPB eggs, and survivorship was highest for all species when they fed on a pure diet of GPA. One native species, H. convergens, and one exotic species, H. axyridis, exhibited significantly lower survivorship on a mixed diet of both CPB eggs and GPA, compared to a pure GPA diet; H. axyridis also took longer to develop from egg to adult when both prey were provided. Survivorship of the two Coccinella spp. was not altered by the inclusion of CPB eggs with GPA, although CPB eggs lengthened the development time of C. transversoguttata. Adult size was not consistently affected by diet for any of the coccinellids. Overall, no ladybird species benefited from the inclusion of potato beetle eggs in its diet. The two Coccinella species responded similarly to the inclusion of CPB eggs, and so we would not expect any difference in the success of coccinellid larval development in potato fields following the replacement of C. transversoguttata by C. septempunctata. Hippodamia convergens and H. axyridis, the two species whose survivorship was depressed by combining CPB egg and aphid prey, were also the two species that consumed the greatest number of CPB eggs during successful larval development. A comparison of total egg consumption by each species cohort suggested that displacement of the other species by H. axyridis would not alter CPB biological control, because the higher per capita feeding rate by H. axyridis larvae compensated for individuals’ greater mortality risk on a diet including CPB eggs.     

Theropithecus atlanticus (Thomas, 1884) (Primates: Cercopithecidae) from the late Pliocene of Ahl al Oughlam, Casablanca, Morocco

The site of Ahl al Oughlam near Casablanca, Morocco, dated to ca. 2·5 Ma, has yielded a good sample of Theropithecus atlanticus (Thomas, 1884), a North African late Pliocene species previously known only by its holotype, a lower molar from Algeria. Theropithecus atlanticus, which can now be much better defined, is clearly distinct from other species of the genus, which is thus more diverse than previously thought. The mandible of T. atlanticus has a very characteristic deep and long post-molar sulcus and a deep and well excavated supra-lateral triangular depression of the ramus, with a sharp postero-inferior ridge. The upper and lower canines are rather large but low. The male P₃is very wide, with well developed posterior crests; the P₄is rounded, with a large talonid and weak notches and clefts. Median lingual notches of the lower molars form an acute angle. Although our incomplete knowledge of T. atlanticus precludes a detailed phylogenetic analysis, we suggest that it arose by clado-genesis from the T. darti–T. oswaldi lineage; it is replaced by the latter species in the Pleistocene.Le gisement de Ahl al Oughlam près de Casablanca (Maroc), daté d'environ 2,5 Ma, a livré une belle collection deTheropithecus atlanticus (Thomas, 1884), espèce du Pliocène supérieur nord-africain qui n'était jusque là connue que par son holotype, une molaire inférieure d'Algérie. T. atlanticus, qui peut maintenant être bien mieux défini, se distingue bien des autres espèces du genre, dont la diversité est ainsi accrue. La mandibule de T. atlanticus est très caractéristique par son espace rétro-molaire vaste et profond, et sa dépression supra-latérale de la branche montante également très profonde, avec un rebord inférieur aigu. Les canines supérieures et inférieures sont grosses mais basses. La P₃mâle est très large, avec des crêtes postérieures très développées; la P₄est arrondie, avec un grand talonide et des sillons peu profonds. Sur les molaires inférieures, le débouché de la vallée médiane forme un angle aigu. Bien que notre connaissance imparfaite de T. atlanticus interdise une analyse phylétique détaillée, nous suggérons une dérivation par cladogenèse à partir de la lignée T. darti–T. oswaldi; cette dernière espèce le remplace au Pléistocène.     

Perkinsus marinus in pleasure oyster Crassostrea corteziensis from Nayarit, Pacific coast of México

Culture of the pleasure oyster Crassostrea corteziensis is emerging as an alternative to the Pacific oyster (Crassostrea gigas) for oyster producers, who face severe mortalities since 1997 in Northwest México. For determining the health status of this species, we conducted a histopathological analysis of cultured populations from two estuaries in the Pacific coast of México. Macroscopical analysis revealed animals with transparent and retracted mantle. Histopathological analysis of these specimens showed tissue alterations and parasitic forms consistent with Perkinsus sp. infection. Stages of the parasite identified included tomont and trophozoites with an eccentric vacuole characteristic of Perkinsus spp. Pieces of tissues of infected oysters were incubated in Fluid Thioglycollate Medium (FTM) resulting in blue–black hypnospores after incubation. The identity of the parasite was confirmed by species specific PCR-based assay in DNA samples from oysters, tissue fractions from FTM cultures, and deparaffined samples with Perkinsus-like parasite detected by histology. Sequencing of positive amplified fragments (307 bp) showed a sequence similar to Perkinsus marinus strain TXsc NTS ribosomal RNA gene (100% coverage and 98% identity, GenBank Accession No. AF497479.1) and to P. marinus, Genomic DNA, (100% coverage and 97% identity, GenBank Accession No. S78416.1). The prevalence of P. marinus varied from 1 to 5% in Boca del Camichín and from 1 to 6% in Pozo Chino. In general, the intensity of infection was moderate. The infection was observed in oysters from 31 to 110 mm of shell length. This is the first record of P. marinus in oysters from the North America Pacific coast and the first record in C. corteziensis. The origin of this parasite in the area is unknown, but it may be associated to introductions of Crassostrea virginica from the East coast of United States of America or Gulf of México.     

Cytogenetic analysis of metaphase chromosomes from pupal testes of four mosquito species using fluorescence <Emphasis Type="Italic">in situ</Emphasis> hybridization technique (FISH)

The DNA probes, P1887, P2405, P2056 (being specific tags for Aedes aegypti genes coding for ribosomal RNA) and a centric heterochromatin probe, K20-1A5, were chosen to hybridize the metaphase chromosomes from the testes of four mosquito species, Culex pipiens, Aedes aegypti, Aedes albopictus and Aedes triseriatus. In addition, a single plasmid, P2392, which contained the three probes, P1887, P2405 and P2056, was also used as chromosome landmark in aedine species. Only the Aedes aegypti metaphase chromosome 1-specific tag, P1887, was conserved in Aedes albopictus, Aedes triseriatus, and Culex pipiens metaphase chromosomes. Aedes triseriatus exhibited two gene loci, on chromosomes 1 and 3, coding for ribosomal RNA per haploid genome. When the specific probes for chromosomes 2 and 3, 2405 and 2056, were used in the fluorescence in situ hybridization technique against the metaphase chromosomes the fluorescent signals were not seen in Aedes albopictus, Aedes triseriatus or Culex pipiens. Also the centric heterochromatin probe, K20-1A5, exhibited strong fluorescent signals on chromosomes 1, 2 and 3 of Aedes aegypti. These fluorescent signals were not observed in metaphase chromosomes derived from the other aedine species, indicating that the centromere sequence can vary within the species.This paper was presented at the Second Arab Conference on Biotechnology and Genetic Engineering, held in the Kingdom of Bahrain, 15–17 April, 2002 and is published here with the endorsement of the Co-ordinator of the Scientific Committee, Professor Essam H. Ghanem, University of Bahrain. Its publication has been delayed because of the ill health of the senior author. Other papers from this conference were published in the July 2003 issue (vol. 19, no. 5).     

Evidence for regular ongoing introductions of mosquito disease vectors into the Galápagos Islands

Wildlife on isolated oceanic islands is highly susceptible to the introduction of pathogens. The recent establishment in the Galápagos Islands of the mosquito Culex quinquefasciatus, a vector for diseases such as avian malaria and West Nile fever, is considered a serious risk factor for the archipelago''s endemic fauna. Here we present evidence from the monitoring of aeroplanes and genetic analysis that C. quinquefasciatus is regularly introduced via aircraft into the Galápagos Archipelago. Genetic population structure and admixture analysis demonstrates that these mosquitoes breed with, and integrate successfully into, already-established populations of C. quinquefasciatus in the Galápagos, and that there is ongoing movement of mosquitoes between islands. Tourist cruise boats and inter-island boat services are the most likely mechanism for transporting Culex mosquitoes between islands. Such anthropogenic mosquito movements increase the risk of the introduction of mosquito-borne diseases novel to Galápagos and their subsequent widespread dissemination across the archipelago. Failure to implement and maintain measures to prevent the human-assisted transport of mosquitoes to and among the islands could have catastrophic consequences for the endemic wildlife of Galápagos.     

Phylogenetic relationships among Puccinia hemerocallidis, P. funkiae, and P. patriniae (Uredinales) inferred from ITS sequence data

Puccinia hemerocallidis and P. funkiae resemble each other morphologically; however, they are biologically and taxonomically distinct, with telia of the former being restricted to species of Hemerocallis and the latter to Hosta species. However, both fungi share a macrocyclic and heteroecious life cycle with Patrinia villosa as the spermogonial and aecial host. An additional microcyclic rust fungus, P. patriniae, is also known on P. villosa. This microcyclic fungus is similar to the two macrocyclic fungi in its telial structure and teliospore morphology. These similarities in morphology and host relationships suggest the three fungi may also share a close evolutionary relationship. To determine the phylogenetic relationships of the three species, a portion of the nuclear ribosomal DNA repeat encoding the ITS and 5.8S subunit regions was amplified by PCR, sequenced, and analyzed. The resulting phylogenetic trees showed that P. hemerocallidis and P. funkiae share a recent common ancestor and that P. patriniae is closely allied with P. hemerocallidis. The results suggest a possible evolutionary derivation of microcyclic P. patriniae from macrocyclic heteroecious P. hemerocallidis, which fits the evolutionary interpretation of correlated species known as Tranzschel's law.     

Pollen-ovule ratios in some Neotropical Araceae and their putative significance

The correlation between pollen-ovule (P/O) ratio and breeding system has generally been analysed with respect either to pollination efficiency, or in terms of sex allocation theory. Pollen/ovule ratios were measured in nine species of Araceae belonging to two genera with bisexual flowers (Anaphyllopsis, Monstera) and three genera with unisexual flowers (Dieffenbachia, Philodendron, Montrichardia). The family Araceae with its unique inflorescence morphology allows the analysis of variations of the P/O ratio with respect to two basal morpho-functional pollination units: the flower or the inflorescence. We found a relationship between the value of the P/O ratio and the breeding system that is partially different from Cruden's results (1977). Some facultative xenogamous species have a higher P/O than the obligatory xenogamous species. A link was found between the P/O and the type of inflorescence, the floral cycle, and the mode of growth.     

Comparative analysis of the reproductive biology of two Peristenus species (Hymenoptera: Braconidae), biological control agents of Lygus plant bugs (Hemiptera: Miridae)

Peristenus digoneutis Loan and Peristenus stygicus Loan, parasitoids of the European tarnished plant bug Lygus rugulipennis Poppius, are established in the United States for biological control of native North American Lygus species, and are being considered for deliberate release in Canada. High lifetime fecundity of parasitoids is considered a desirable attribute of biological control agents and therefore, an understanding of parasitoid reproductive biology is required. In the present study, the potential lifetime fecundity of both agents was compared under laboratory conditions to estimate the potential impact of Peristenus species on Lygus. Synovigenic P. digoneutis and P. stygicus females oviposited most actively in the first two weeks of their lifetime, with a maximum average daily oviposition rate after five days. The maximum number of eggs laid per day was 83 eggs for P. stygicus, and 36 eggs for P. digoneutis. P. digoneutis has an average potential lifetime fecundity of 385 ± 35 SE eggs produced over 22 ± 3 SE days. In contrast, P. stygicus females have a 50% higher mean potential lifetime fecundity reaching 782 ± 65 SE eggs over 28 ± 1 SE days. A positive correlation between lifetime fecundity and body size was found only for P. stygicus, and both species showed a significant relationship between lifetime fecundity and oviposition period. The present study demonstrates that the fecundity of P. digoneutis and P. stygicus is considerably higher than previously reported. Based on these findings, P. stygicus appears to be the most effective biological control agent for Lygus lineolaris (Palisot de Beauvois) when only fecundity is taken into consideration.     

Evolution and phylogenetic relationships within Porinaceae (Ostropomycetidae), focusing on foliicolous species

A phylogeny of the lichen family Porinaceae using mitochondrial SSU rDNA sequences is presented, with special focus on foliicolous taxa. Fifty specimens of 28 mostly tropical species, representing eight species groups of Porina as well as the genus Trichothelium, were analysed together with species of other members of Ostropomycetidae, and using Agyriaceae as outgroup. We performed the phylogenetic analyses with a Bayesian approach and under the criterion of maximum parsimony. Four main clades can be distinguished: the P. nitidula-group s. lat. (including Trichothelium, P. papillifera and P. rubescens), the Porina epiphylla-group s. lat. (including the P. radiata-, the P. nucula-, the P. imitatrix- and the P. epiphylla-group s. str.) and two clades of the P. rufula-group. The genus Porina as understood by all recent concepts is paraphyletic, and Trichothelium is nested within the Porina nitidula-group. The non-setose P. repanda forms a monophyletic clade with Trichothelium. The tree does not support a monophyletic origin of substrate preferences or photobiont selection. Species-specific associations with morphologically different trentepohlioid photobionts mapped on the tree suggest that closely related mycobiont species switch between different types of algae.     

Late-Pleistocene and early Holocene history of the canid fauna of Europe (Canidae)

In the sub-fossil assemblages of Europe the red fox is clearly the most frequent carnivorous mammalian species with a total of 1553 records. In depositions from the Weichselian Glacial the red fox Vulpes vulpes is, a typical representative of the Holocene fauna, already recorded in 100 assemblages. The Iberian peninsula, Italian peninsula and Balkans were theorised as glacial refugia. Well-founded facts give reason to believe that V. vulpes was also distributed in the Carpathian refuge. Later on, the Crimean peninsula would also appear to be a possible glacial refuge of the red fox.In the last warmer complex of interstadials during the Pleni-Glacial (Hengelo-Denekamp, 38,000–25,000 BC) the red fox was distributed in central Europe. Its distribution during this epoch extended at least in part to southern England. The earliest well-dated records of V. vulpes in central Europe after the Maximum Glaciation lie between 14,000 and 13,500 BC. Already during the early Late-Glacial (13,500 BC) the red fox appeared in typical glacial faunal communities. A separation to glacial refugia was only possible for 10,000 years.During the last warmer Pleni-Glacial complex of interstadials (38,000–25,000 BC) in central Europe a sympatric distribution of the arctic fox (Alopex lagopus) and the red fox probably existed. During the Last Glacial Maximum (22,000–18,000 BC) the arctic fox was exclusively distributed in central Europe, outside of the refuges. The combined distribution of A. lagopus and V. vulpes during the Late-Glacial (15,000–9500 BC) in central Europe, with the probable exception of the Allerød, is precisely documented by sub-fossil assemblages.In the Pleni-Glacial the wolf Canis lupus was distributed in geographic regions that served as glacial refugia of more warm-climate adapted species. Concerning the wolf no drastic decrease of the distribution is assumed. The Holocene presence of C. lupus is probably not caused by recolonisation.

Zusammenfassung

Die Entwicklung der Canidenfauna Europas im Spätpleistozän und frühen HolozänIn den subfossilen Ablagerungen ist Vulpes vulpes in Europa mit 1553 Nachweisen das mit Abstand am häufigsten nachgewiesene Raubsäugetier. Allein in den Ablagerungen des Weichselglazials konnte der Rotfuchs bereits in 100 Fundkomplexen nachgewiesen werden. Als Glazialrefugium des Rotfuchses wird die Iberische Halbinsel sicher identifiziert. Eine Verbreitung der Art während des Kältemaximums wird außerdem auf der Apenninen-Halbinsel sowie der Balkan- Halbinsel vermutet. Außerdem liegen fundierte Fakten für die Annahme vor, dass V. vulpes im Karpatenrefugium verbreitet war. Auf der Halbinsel Krim scheint ein Glazialrefugium für des Fuchses möglich.Während des letzten wärmeren Interstadial-Komplexes im Hochglazial (Hengelo-Denekamp, ca. 38.000–25.000 v. Chr.) war Mitteleuropa vom Rotfuchs besiedelt. Die nördliche Arealgrenze der Art war innerhalb dieses Klimaabschnitts mindestens zeitweise bis nach Südengland ausgedehnt. Die frühesten, zeitlich relativ gut abgesicherten Nachweise von V. vulpes nach der Weichsel-Maximalvereisung in Mitteleuropa liegen etwa zwischen 14.000–13.500 v. Chr. Schon im frühen Spätglazial (ca. 13.500 v. Chr.) kam der Rotfuchs im nördlichen Mitteleuropa in typischen glazialen Faunengemeinschaften vor. Eine Disjunktion des Areals während der letzten Vereisung kann für höchstens 10.000 Jahre stattgefunden haben. Es wird angenommen, dass während des Hengelo-Deenekamp Interstadials ein sympatrisches Vorkommen von Eisfuchs Alopex lagopus und Rotfuchs V. vulpes in Mitteleuropa existierte. Nur zur Zeit des absoluten Kältemaximums (ca. 22.000–18.000 v. Chr.) war außerhalb der Refugialgebiete in Mitteleuropa ausschließlich A. lagopus verbreitet. Das gemeinsame Vorkommen (von A. lagopus und V. vulpes) während des gesamten Spätglazials in Mitteleuropa, wahrscheinlich mit Ausnahme des Allerød-Interstadials, ist präzise belegt.Während des Hochglazials war Canis lupus auch in geografischen Regionen verbreitet, die für an wärmeres Klima gebundene Tierarten den Charakter von Glazialrefugien hatten. Beim Wolf C. lupus kann keine extreme Arealverringerung während der Weichseleiszeit angenommen werden. Das holozäne Vorkommen von C. lupus in Mitteleuropa dürfte daher nicht generell auf eine Rekolonisation zurückzuführen sein.     

The effects of phosphorus nutrition and soil pH on the growth of some ancient woodland indicator plants and their interaction with competitor species

The forest under-storey herbs Anemone nemorosa, Lamiastrum galeobdolon and Veronica montana are generally considered indicator species of old, broadleaved woodland sites where the soil fertility is often low. In a glasshouse bioassay, however, all three species not only showed large positive growth responses to supplied P concentrations (0–10mgL ^–1) solutions, but also tolerated high P concentrations (20–40mgL ^–1), well above those normally found in their natural habitat. Plants responded by raising the concentrations of P in their shoot and root tissues and increasing their biomass, resulting in an increased P uptake. A shade-tolerant competitor species, Urtica dioica, also grew vigorously across the full range of P concentrations, restricting the growth of the woodland species. This emphasises the difficulty of establishing semi-natural woodland vegetation in the presence of competitor species, for example in situations where new woodlands are planted on fertile ex-agricultural soils containing large residual concentrations of P. The influence of soil pH on the growth and nutrient relations of A. nemorosa, L. galeobdolon, V. montana, Poa trivialisandU. dioicawas determined in a separate experiment using an ex-arable soil as the growing medium with pH levels adjusted from 7.4 to 5.8 and 4.3 respectively. Acidifying the soil enhanced growth, but reduced the concentrations of N, P and K in the leaves of all three woodland species, probably due to dilution of these minerals in the increased dry matter production. The competitor species (P. trivialis and U. dioica) responded in similar manner to the woodland indicator species. These results suggest that manipulating soil pH as a means of facilitating the establishment of woodland indicator species in new farm woods is unlikely, in the short term, to be effective where competitor species are present.     

广西凭祥口岸首次截获有害生物台湾坡天牛Pterolophia formosana

台湾坡天牛一般随着木制品及包装制品进行远距离传播入境。目前我国台湾地区和日本有分布,在我国大陆地区尚未见该虫的发生报道。2019年5月凭祥口岸从来自越南的相思木板上截获了台湾坡天牛,为我国大陆首次截获。通过显微形态特征的观察和测量进行台湾坡天牛种类鉴定。台湾坡天牛与近似种的主要区别:其鞘翅基部具明显的黑褐色宽横带。通过入侵可能性分析,来自我国台湾地区、日本的台湾坡天牛入侵我国大陆地区的可能性很大。台湾坡天牛在我国广东、广西、福建等地区定殖和扩散风险很大。一旦传入我国,将对我国的农林安全造成巨大威胁,各口岸应对进境的木制品及包装加强检验检疫。     

Molecular and morphological data suggest that Spinibarbus caldwelli (Nichols) (Teleostei: Cyprinidae) is a valid species

The taxonomic problem of the cyprinid species of genus Spinibarbus, occurring in southern China and northern Vietnam, was resolved on the basis of molecular and morphological analyses. Spinibarbus caldwelli and Spinibarbus hollandi have a smooth posterior edge of the last unbranched dorsal fin ray among species in the genus. Spinibarbus caldwelli is currently regarded as a junior synonym of S. hollandi because of ambiguities in diagnostic characters. In this article, 11 mtDNA cytochrome b sequences of Spinibarbus specimens were analyzed together with Barbodes gonionotus and Puntius conchonius as outgroups. Our results showed that specimens identified as S. hollandi from Taiwan were different from those from the Asian mainland at a high level of genetic divergence (0.097–0.112), which is higher than that between the two valid species, S. sinensis and S. yunnanensis (0.089), and suggested that Taiwan specimens should be considered as a different species from the Asian mainland one. In a molecular phylogenetic analysis, the sister-group relationship between Taiwan specimens and the Asian mainland specimens was supported strongly by a high confidence level (100% in bootstrap value). Further analysis of morphological characters showed that overlap of diagnostic characters is much weaker than previously suggested. Taiwan specimens had 8 branched rays in the dorsal fin, whereas those from the mainland had almost 9–10. The molecular and morphological differences suggest S. caldwelli to be valid. The molecular divergence shows the genetic speciation of S. hollandi and S. caldwelli might have occurred 5.6–4.9 million years ago; the former could be a relict species in Taiwan, and the latter dispersed in the Asian mainland.