Seasonal prevalence of mosquitoes collected from light traps in the Republic of Korea, 2006

Adult mosquito surveillance was conducted during 2006 at 22 US Army and Air Force installations and two training sites located in six provinces in the Republic of Korea. Adult mosquitoes were collected in New Jersey light traps from 1 May through 15 October 2006 to determine threshold levels to initiate pesticide applications based on trap indices. In total 16 217 adult mosquitoes [13 612 (83.9%) females and 2605 (16.1%) males] comprising 16 species (including five members of the Anopheles sinensis Group) belonging to eight genera were collected. Females of the most commonly collected species were members of the Anopheles sinensis Wiedemann Group (58.9%), followed by Aedes vexans nipponii (Theobald) (21.3%), Culex tritaeniorhynchus Giles (11.8%) and Culex pipiens Coquillett (5.2%). Trap indices varied widely for species over their range, due in part, to their geographical distribution and degree of association with urban or rural communities.     

Morphological and molecular investigation of polymorphism and cryptic species in tanaid crustaceans: implications for tanaid systematics and biodiversity estimates

A combination of traditional taxonomic procedures and molecular techniques has provided new insight into the problems of cryptic species and sexual and ontogenetic polymorphism in the Tanaidacea. Using polymerase chain reaction and DNA markers, three cryptic species of Paratanais were identified. PCR primers were used to amplify the divergent internal transcribed spacers (ITS) of these species. Restriction digestion of the amplified rDNA generated species specific DNA banding. Male and five female stages of Paratanais maleticus sp. nov. and two other new species, P. malign us and P. perturbatius , are described. Morphological variation, both sexual and ontogenetic, was found in several generic characters of Paratanais and required the diagnosis to be modified. The identification of three undescribed cryptic species from a single microhabitat in a well studied, shallow water and easily accessible locality, demonstrate that the biodiversity of tanaid crustacean is significantly underestimated.     

Review of family Lucanidae (Insecta: Coleoptera) in Korea with the description of one new species

This paper provides a review of the family Lucanidae in Korea, which consists of 17 species belonging to 9 genera. One new species, Dorcus tenuihirsutus sp. nov., is described and the following taxonomical changes are proposed: Aegus laevicollis Saunders, 1854 is newly identified as Aegus laevicollis subnitidus Waterhouse, 1873; Macrodorcas striatipennis Motschulsky, 1861 is removed from the Korean fauna because this record is thought to have been based on the misinterpretation of locality and misidentification; Neolucanus saundersii Parry, 1864 is removed from the Korean fauna because this record is thought to have been based on misidentification.     

Isolation and characterization of polymorphic microsatellite markers of Anopheles sinensis,a malaria vector mosquito in the East Asia region

Eleven polymorphic dinucleotide (GA and CA) microsatellites were isolated and characterized in the mosquito Anopheles sinensis; this species is distributed over the East Asia region and is a primary vector of malaria, particularly in Korea. The number of alleles per locus ranged from 4 to 13. The observed heterozygosity (H_O) and expected heterozygosity (H_E) varied from 0.30 to 0.89 and from 0.59 to 0.90, respectively. These microsatellites could be useful in studying the evolution of the widely distributed A. sinensis in diverse environments.     

Geographic and stratigraphic change in the morphology of Triarthrus beckii (Green) (Trilobita): a test of the Plus ça change model of evolution

The Plus ça change model predicts that deepwater trilobite species such as Triarthrus should exhibit gradual phyletic evolution. A detailed stratigraphic sequence of Triarthrus beckii specimens considered together with geographically separated samples from a single time interval provide a test of the Plus ça change model. We examined geographic patterns of variation in cranidial shape based on specimens from four approximately synchronous levels within the Upper Ordovician (lower Edenian) strata of New York, Québec, Kentucky and Pennsylvania. All geographic populations differ in mean size, except for New York and Pennsylvania. Because allometry is present in both meraspid and holaspid phases of the trilobite, size effects on shape were removed by ontogenetic standardization. Cranidial shapes were then compared among the four study sites and eight stratophenetic samples from New York, obtained by subdividing our Mohawkian Composite Standard Section into 20-m-thick intervals. Goodall's F-test of pairwise comparisons of cranidial shape between eight subintervals in New York and the other three populations are all significant. Geographic variation in cranidial size and shape in T . beckii appears to display a gradient or cline-like pattern that is related to paleogeography. Although cranidial shape is not entirely static within the New York stratophenetic series, it is in all cases different from that sampled elsewhere in the region. Thus, there is no evidence of wholesale immigration and emigration among the geographic areas. Instead, the geographic gradient of T . beckii shape variation may have remained fairly stable over ca. 3 million years during the mid-Chatfieldian to early Edenian interval. This result is indicative of stasis. Consequently, the evolutionary history of T . beckii contradicts the Plus ça change model.     

Two-dimensional gel analysis of stress proteins identified in Chironomus flaviplumus (Diptera: Chironomidae) exposed to 4-nonylphenol

Toxicity of 4-nonylphenol (4-NP) in the Chironomidae Chironomus flaviplumus was analyzed using a proteomics approach that involved identifying proteins by two-dimensional polyacrylamide gel electrophoresis (2-D PAGE). Proteome analysis of 4-NP-treated samples on silver stained gels found alterations in the expression levels of three proteins compared with control samples. Hsp70 proteins, so-called stress proteins, were studied in Chironomus flaviplumus exposed to different concentrations of 4-nonylphenol (0, 30, 100, 150, 300 and 600 mg/L) in the laboratory and in the field in captured animals from site 1 (1 km from a chemical factory) and site 3 (16 km from a chemical factory). Hsp70 proteins were found in all samples tested, including controls, but differed in their expression levels. At more polluted sites (site 1), the samples treated with higher concentrations of 4-NP more strongly expressed Hsp70. 2-D spots were induced or enhanced in gels following injection of 4-NP. Therefore, the induction of stress protein expression in Chironomus flaviplumus, in particular Hsp70, can be used as a biomarker for the evaluation of environmental conditions.     

External Structures of the Antennae and Mouth Parts of the Fourth Instar of Chironomus flaviplumus and Chironomus salinarius (Diptera: Chironomidae)

Chironomidae is usually the most abundant macroinvetebrate in freshwater. They form an important part of the foodweb, and also have long been known as indicators of water quality. However, there is a great deal of difficulty in its identification. Such is due to the complexity of larval taxonomy. The external fine structures of the mouth parts and antennae of 4th instar larva C. flaviplumus and C. salinarius were examined using scanning electron microscopy (SEM). The antennae of the fourth instar larvae of C. flaviplumus and C. salinarius are short and composed of five segments. They consist of a scape, pedical, and three flagellar subsegments. The maxilla palps have 10 sensilla basiconica on its distal surface. They show the three morphological groups in the following numbers: six apical sensillae, three medial sensillae, and one lateral sensillae. The mandibles have strong apical and lateral teeth. These sensory structures are situated on the head capsule, each of which are represented with images to elucidate the identification of chironomidae.     

Evaluation of Repellency Effect of Two Natural Aroma Mosquito Repellent Compounds,Citronella and Citronellal*

Repellent efficacies of two natural aroma compounds, citronella and citronellal, against mosquitoes, Culex pipiens pallens, were evaluated both in field and in vitro. In vitro, the experiment was conducted with three controlled bands impregnated with 30% citronella extract, 15% citronella extract and 30% citronellal extract, and with bands impregnated 30% citronella in field. Data was obtained by the means of counting numbers bitten by mosquitoes per unit time, namely human bait method. Percentage repellencies of above three controlled bands were calculated at 86%, 73%, and 78%, respectively in vitro, and 80% in field, showing high repellent effectiveness against mosquitoes. This estimation was also confirmed by t‐test compared between control group and each experimental group.