The decay of similarity over geographical distance in parasite communities of marine fishes

Aim We evaluate, for the first time, the decay of similarity over distance in four species of marine fishes with different vagility: Trachurus murphyi (pelagic, highly vagile), Merluccius gayi (demersal, highly vagile), Sebastes capensis (demersal, low vagility) and Hippoglossina macrops (benthic, non‐vagile). Location We use our own data of the species composition of parasite communities in four host species: T. murphyi (Perciformes), M. gayi (Gadiformes), H. macrops (Pleuronectiformes) and S. capensis (Scorpaeniformes), from the coast of Chile and southern Argentina. Trachurus murphyi, M. gayi and H. macrops in the area studied live closely associated with the cold waters of the Humboldt Current System, while S. capensis in southern Chile is associated with the fjord areas south of c. 43° S, and in Argentina this species lives in close association with the cold water of the Malvinas Current, which mixes with the warm water of the Brazilian Current in the sampled area. Thus, for all four host species there are no known geographical (oceanographic) barriers that interrupt their continuous distributions. Methods Fish were collected and frozen (?18 °C) until examination in the laboratory. After thawing, each visceral organ was dissected separately, washed in running water, filtered using a mesh of 0.25 mm, and examined under a stereomicroscope (20×). For S. capensis, only ectoparasites were included in this study because data on endoparasites for some locations are not available. The approach of Poulin [Journal of Biogeography 30 (2003) 1609] was used. For each host species, we computed similarity in parasite composition using the Bray–Curtis distance on a presence/absence matrix. Similarity between each pair of localities was correlated (linear regression on raw and transformed data) with the distance (in nautical miles) among those sites. Results Among conspecific populations of host fish, there was no correlation between sample size and parasite species richness. The same pattern was evident when all host populations were pooled and treated as a single sample. Except for H. macrops, an important proportion of the geographical ranges of the host species was covered. The decay in similarity of parasite communities over distance was recorded in three of the four hosts analysed. For H. macrops, no relationship between distances and decay of similarity was evident. A linear regression on non‐transformed data provided a good fit, and the regression on log(n + 1) does not change significantly for both r² and probability, but slopes are smaller for log‐transformed than for non‐transformed data. Main conclusions Three of the four fish parasite systems studied fit well with the expected decay of similarity over distance. The slopes of the relationship between distance and similarity in the marine fishes studied are lower, but significant (three orders of magnitude) than those recorded in freshwater fishes by Poulin (2003) . In our case, Hippoglossina macrops (benthic, non‐vagile host) does not show any relationship, suggesting homogeneity over the geographical area studied for this species.     

Molecular phylogeny of the genus Pieris (Ericaceae) with special reference to phylogenetic relationships of insular plants on the Ryukyu Islands

Phylogenetic relationships within the genus Pieris (Ericaceae) were investigated based on the rbcL and matK genes along with five spacer sequences of chloroplast DNA to address questions regarding the phylogeography of the genus in association with insular plants on the Ryukyu Islands. The most parsimonious trees indicated that P. floribunda from eastern North America is a sister taxon to the remaining taxa examined, and suggested that the East Asian taxa examined are monophyletic. A morphologically cohesive group, section Pieris, was revealed to be paraphyletic. Within the East Asian clade, insular endemics from the Ryukyu Islands, Taiwan, and mainland Japan formed a sister group to P. formosa from the Himalayas and southern China. Our data suggest that the insular endemics of the Ryukyu Islands and Taiwan arose via allopatric divergence as a result of a paleogeographical land configuration of a landbridge during the early–middle Pleistocene in the Quaternary Period.     

粤东地区野生杜鹃花资源及其开发利用

经调查统计,粤东地区野生杜鹃花有11种．其中．该区特产2种．模式植物2种,主要分布在该区北部山区。在调查的基础上就粤东地区野生杜鹃花资源的开发利用提出建议。     

Male share of provisioning is not influenced by actual or apparent loss of paternity in western bluebirds

Approximately 45% of western bluebird (Sialia mexicana) femaleshave some chicks in the nest that are not sired by their socialmates. Extrapair fertilizations account for 42% of offspringin these nests and 19% of nestlings overall. I tested the hypothesisthat males reduce nestling provisioning when their certaintyof paternity or share of paternity is reduced. Capture and detentionof socially monogamous males for 1 h or 24 h during the layingperiod reduced males' copulatory access and their ability tomate guard, increasing the frequency with which extrapair malesintruded and attempted to copulate with resident females. Malesdetained during laying did not reduce their share of feedingtrips compared to control males detained during incubation,compared to unmanipulated males, or compared to males that werecaptured but not detained. Males detained on territory for 1h during the laying period did not reduce their share of feedingtrips when they observed male intrusion, nor when they observedtheir mates accepting extrapair copulations. Males that witnessedtheir mates accepting extrapair copulations did not reduce theirshare of risk in provisioning. Genetic fingerprinting at nonexperimentalnests indicated that males also failed to reduce their feedingcontributions when their estimated share of paternity was reduced,even when a helper male was present to reduce the impact onnestlings. These results suggest that male western bluebirdsdo not make significant adjustments in their share of provisioningwhen they have evidence of partial paternity loss. Togetherwith prior results, this study suggests that western bluebirdmales use an all-or-none rule, contributing approximately halfof the parental provisioning at nests, as long they have somecopulatory access to the female during egg laying.     

Eastern Asian endemic seed plant genera and their paleogeographic history throughout the Northern Hemisphere

We review the fossil history of seed plant genera that are now endemic to eastern Asia. Although the majority of eastern Asian endemic genera have no known fossil record at all, 54 genera, or about 9%, are reliably known from the fossil record. Most of these are woody （with two exceptions）, and most are today either broadly East Asian, or more specifically confined to Sino-Japanese subcategory rather than being endemic to the Sino-Himalayan area. Of the ＂eastern Asian endemic＂ genera so far known from the fossil record, the majority formerly occurred in Europe and/or North America, indicating that eastern Asia served as a late Tertiary or Quaternary refugium for taxa. Hence, many of these genera may have originated in other parts of the Northern Hemisphere and expanded their ranges across continents and former sea barriers when tectonic and climatic conditions allowed, leading to their arrival in eastern Asia. Although clear evidence for paleoendemism is provided by the gymnosperms Amentotaxus, Cathaya, Cephalotaxus, Cunninghamia, Cryptomeria, Glyptostrobus, Ginkgo, Keteleeria, Metasequoia, Nothotsuga, Pseudolarix, Sciadopitys, and Taiwania, and the angiosperms Cercidiphyllum, Choerospondias, Corylopsis, Craigia, Cyclocarya, Davidia, Dipelta, Decaisnea, Diplopanax, Dipteronia, Emmenopterys, Eucommia, Euscaphis, Hemiptelea, Hovenia, Koelreuteria, Paulownia, Phellodendron, Platycarya, Pteroceltis, Rehderodendron, Sargentodoxa, Schizophragma, Sinomenium, Tapiscia, Tetracentron, Toricellia, Trapella, and Trochodendron, we cannot rule out the possibility that neoendemism plays an important role especially for herbaceous taxa in the present-day flora of Asia, particularly in the Sino-Himalayan region. In addition to reviewing paleobotanical occurrences from the literature, we document newly recognized fossil occurrences that expand the geographic and stratigraphic ranges previously known for Dipelta, Pteroceltis, and Toricellia.     

The Arabian scad Trachurus indicus, a new Indo-Pacific species in the Mediterranean Sea

The Arabian scad Trachurus indicus is recorded for the first time from the Mediterranean Sea (Iskenderun Bay, Turkey). The presence of this Indo-Pacific fish in the Mediterranean Sea is probably because of migration from the Red Sea via the Suez Canal.     

An Examination of Scale-Dependent Resource Use by Eastern Hognose Snakes in Southcentral New Hampshire

ABSTRACT The decline of many snake populations is attributable to habitat loss, and knowledge of habitat use is critical to their conservation. Resource characteristics (e.g., relative availability of different habitat types, soils, and slopes) within a landscape are scale-dependent and may not be equal across multiple spatial scales. Thus, it is important to identify the relevant spatial scales at which resource selection occurs. We conducted a radiotelemetry study of eastern hognose snake (Heterodon platirhinos) home range size and resource use at different hierarchical spatial scales. We present the results for 8 snakes radiotracked during a 2-year study at New Boston Air Force Station (NBAFS) in southern New Hampshire, USA, where the species is listed by the state as endangered. Mean home range size (minimum convex polygon) at NBAFS (51.7 ± 14.7 ha) was similar to that reported in other parts of the species’ range. Radiotracked snakes exhibited different patterns of resource use at different spatial scales. At the landscape scale (selection of locations within the landscape), snakes overutilized old-field and forest edge habitats and underutilized forested habitats and wetlands relative to availability. At this scale, snakes also overutilized areas containing sandy loam soils and areas with lower slope (mean slope = 5.2% at snake locations vs. 6.7% at random locations). We failed to detect some of these patterns of resource use at the home range scale (i.e., within the home range). Our ability to detect resource selection by the snakes only at the landscape scale is likely the result of greater heterogeneity in macrohabitat features at the broader landscape scale. From a management perspective, future studies of habitat selection for rare species should include measurement of available habitat at spatial scales larger than the home range. We suggest that the maintenance of open early successional habitats as a component of forested landscapes will be critical for the persistence of eastern hognose snake populations in the northeastern United States.     

Revision of the rove beetle genus Antimerus (Coleoptera, Staphylinidae, Staphylininae), a puzzling endemic Australian lineage of the tribe Staphylinini

The genus Antimerus Fauvel, 1878, endemic to eastern Australia and Tasmania and a phylogenetically enigmatic member of the large rove beetle tribe Staphylinini, is revised. The genus and each of its four previously known species are redescribed, and a lectotype is designated for Antimerus punctipennis Lea, 1906. Five species are described as new: Antimerus metallicussp. n., Antimerus jamesrodmanisp. n., Antimerus gracilissp. n., Antimerus bellussp. n. and Antimerus monteithisp. n., so that the number of known species in this genus now totals nine. For the first time Antimerus larvae are described, tentatively identified as Antimerus smaragdinus Fauvel, 1878, Antimerus punctipennis and Antimerus metallicus. Available distributional and bionomic data are provided for each species and summarized in the discussion. Adult and larval morphology of Antimerus and its distribution patterns are discussed in the broader context of new data on the evolution of the entire tribe Staphylinini, and with respect to the formation of the Australian fauna of this tribe. The phylogenetic position of Antimerus within Staphylinini remains unresolved pending a targeted formal study. However, a majority of currently available data suggests that it could be a basal member of the recently recovered monophyletic clade of Staphylinini tentatively called "Staphylinini propria".     

Estimating the impact of oyster restoration scenarios on transient fish production

Oyster reef restoration projects are increasing in number both to enhance oyster density and to retain valuable ecosystem services provided by oyster reefs. Although some oyster restoration projects have demonstrated success by increasing density and biomass of transient fish, it still remains a challenge to quantify the effects of oyster restoration on transient fish communities. We developed a bioenergetics model to assess the impact of selected oyster reef restoration scenarios on associated transient fish species. We used the model to analyze the impact of changes in (1) oyster population carrying capacity; (2) oyster population growth rate; and (3) diet preference of transient fish on oyster reef development and associated transient fish species. Our model results indicate that resident fish biomass is directly affected by oyster restoration and oyster biomass, and oyster restoration can have cascading impacts on transient fish biomass. Furthermore, the results highlight the importance of a favorable oyster population growth rate during early restoration years, as it can lead to rapid increases in mean oyster biomass and biomass of transient fish species. The model also revealed that a transient fish's diet solely dependent on oyster reef‐derived prey could limit the biomass of transient fish species, emphasizing the importance of habitat connectivity in estuarine areas to enhance transient fish species biomass. Simple bioenergetics models can be developed to understand the dynamics of a system and make qualitative predictions of management and restoration scenarios.