The present revisional work is based on very large collections made by the first and second authors during the course of studies. Most specimens of sarcophagid flesh flies were made by the authors during the field surveys programmed by the Sarawak Museum Department, Kuching, Malaysia from 2005 to 2019. A total of 24 genera and 59 species is recorded. Two new genera, Omarisca gen. nov. and Zulisca gen. nov. are established for two peculiar species found in mangroves. Also eight new species are described: Myorhina miyagii sp. nov., M. tomae sp. nov., Burmanomyia barioensis sp. nov., B. pseudoborneensis sp. nov., Sarcorohdendorfia kerohi sp. nov., S. okazawai sp. nov., Hosarcophaga palustris sp. nov., and H. puteri sp. nov. The following seven species are newly recorded from Malaysia: Senotainia albifrons (Rondani, 1859), Burmanomyia aureomarginata (Shinonaga & Tumrasvin, 1979), Hosarcophaga auricauda (Ho, 1938), H. serrata (Ho, 1938), Parasarcophaga idmais (Séguy, 1934), P. montiblensis (Sugiyama, 1990) and P. walshi (Ho, 1938), Revised identification keys to the Malaysian species are provided.
The climatic conditions are the most plausible reason for the potential outbreaks of Aedes albopictus. The effect of climate change on vegetation is expediting the mosquito breeding sites that have an impact on the larval and adult growth. Here, we compared the effects of vegetation, bamboo (Phyllostachys pubescens), cherry (Prunus×yedoensis) and beech (Castanopsis sieboldii), on the larval growth of Ae. albopictus. The highest larval mortality was observed in cherry, conversely, the lowest was in bamboo. Larval development and adult emergence of cherry and beech were slower than those of bamboo. Female body size was larger when larvae raised with the bamboo compared to cherry plants. Ae. albopictus females oviposited more eggs in bamboo vegetation, however, adults reared by cherry plants laid less amount of eggs. Per capita performance of Ae. albopictus on bamboo vegetation was higher for the population growth compared to cherry and beech. Thus, Ae. albopictus were affected by bamboo vegetation that might have influenced the larval and adult growth. Our findings suggested that bamboo plants should be avoided in future plantation programs near the urban areas, as it might harbor a potential habitat for Ae. albopictus.
The preference of ovipositing Megaselia scalaris for dead adult cockroaches was examined experimentally using the following 6 species: Blattella germanica, Periplaneta fuliginosa, P. brunnea, P. japonica, P. americana, and Blatta orientalis. Five female and 1 male M. scalaris were released into an experimental cage, and exposed to dead adult cockroaches of 6 different species for 48 hr. There was an aggregated distribution of the number of eggs on dead cockroaches, suggesting the preference of ovipositing females. The chi-square test of independence demonstrated significant differences in egg numbers between male and female cockroaches of the same species for 4 cockroach species. The two-way ANOVA of egg numbers on dead cockroaches revealed that sex was significant but the cockroach species was not significant. The degree of preferential oviposition of M. scalaris on female cockroaches varied among the 6 cockroach species. The proportion of eggs laid on female cockroaches was the highest for B. orientalis (97.0%) and the lowest for P. fuliginosa (53.29%). The presence of factors other than species and sex of dead cockroaches was strongly suggested for the preferential oviposition of M. scalaris.
A new mosquito species, Topomyia (Topomyia) sarawakensis Miyagi, Toma and Okazawa is described from Sarawak, Malaysia. The adult male and female, pupa, and fourth-instar larva are described in detail. Illustrations of the male genitalia, pupa, and fourth-instar larva of the species are also provided. The larvae of this species breed in the water accumulation of the phytotelmata (leaf axils) of ginger plants (Boesenbergia sp.), Pandanus sp., and taro plants (Alocasia and Colocasia) in mountain forests.
The increase in the number of imported cases of dengue fever in Japan is of particular concern as Aedes albopictus is a vector of dengue fever. Due to the potential for insecticide resistance and the impact of insecticides on non-target species, increased attention is being paid to alternative methods of pest control. Placing salt in used tires has been recommended by the Ministry of Health, Labor and Welfare in Japan as a means of controlling mosquitoes. However, the effectiveness of salt as a larvicide against Ae. albopictus are currently unclear. This study examined the acute toxicity of sodium chloride against first and fourth larval instars of Ae. albopictus. Acute toxicity tests were conducted according to World Health Organization guidelines. The susceptibility of Ae. albopictus larvae was tested against 0.25%, 0.5%, 0.75%, 1.00%, 1.25% and 1.5% NaCl solutions. Larval mortality was correlated with an increase in NaCl concentration and exposure duration. First instar Ae. albopictus larvae were more sensitive to NaCl than fourth instar, and 72-h LC90 values for first and fourth larval instars were 0.49% and 1.01% NaCl, respectively. Our results suggest that the application of 0.5% NaCl to a habitat for 3 days is effective for Ae. albopictus control.
Surveillance of vector mosquitoes has been conducted in Tokyo since 2004, and Aedes albopictus and Culex pipiens complex were identified as the dominant and widely-distributed species in Tokyo Metropolis. We performed PCR-based identification of the Cx. pipiens complex that we collected using CO2 baited-traps from 25 sites in Tokyo Metropolis area between 2018 and 2019. In 2019 mosquito larvae were collected from catch basins at 9 sites, reared to adult, and a part of the emerged Cx. pipiens comlex were identified by PCR-based method. As a result, Cx. quinquefasciatus and the hybrids between Cx. quinquefasciatus and Cx. pipiens complex (excluding Cx. quinquefasciatus) were identified in Tokyo Metropolis area for the first time. Continuous field survey is required whether Cx. quinquefasciatus have already been distributed or not in Tokyo Metropolis.