Genetic diversity, genetic structure and demographic history of the ticks infesting beef cattle in Thailand were examined based on mitochondrial cytochrome c oxidase I (cox1) sequences. Tick samples were collected in 12 provinces in upper-northeastern Thailand. Three species were found; Rhipicephalus microplus, R. sanguineus, and Haemaphysalis bispinosa. Of these, R. microplus was by far the most abundant species in beef cattle and was widely distributed throughout the area. No cox1 sequence variation was found in the R. sanguineus or H. bispinosa specimens collected. Low nucleotide diversity but high haplotype diversity was observed in R. microplus. All collected R. microplus specimens belonged to lineage A. Mismatch-distribution analysis, as well as Tajima's D and Fu's Fs tests, provided evidence of recent demographic expansion. A subsample of tick specimens was investigated for presence of Anaplasma and Ehrlichia using a fragment of the 16S rRNA gene. Three species of Anaplasma were detected from R. microplus; Anaplasma marginale (19.08%), Anaplasma platys (1.97%) and unidentified Anaplasma strain (0.66%). The infection rate of Ehrlichia was 7.24% (two ticks were infected with E. minasensis (1.97%) and eight with an unidentified Ehrlichia strain (5.26%). No infections were found in R. sanguineus or H. bispinosa. This is the first report of A. platys and E. minasensis in cattle ticks in Thailand, providing information for future epidemiological surveys and control strategies in this region.

A new black fly species of the subgenus Asiosimulium Takaoka & Choochote of the genus Simulium was recognized from northeastern Thailand based on morphology, mitochondrial DNA and ecology. This black fly species has similar morphological characteristics to Simulium oblongum Takaoka and Choochote that was also described from the same geographic region in all life stages. However, this new species could be distinguished at the adult stage by coloration of the maxillary palp and in the larval stage by the presence of a pigmented subesophageal ganglion that is lacking in S. oblongum. Genetic distance and phylogenetic analyses based on mitochondrial cytochrome c oxidase I sequences clearly differentiated the two species with minimum genetic distance of 3.51%. These species are also ecologically isolated as S. oblongum is found only at low elevation (1,100 m above sea level).

Understanding the factors associated with the species diversity and distribution of insect vectors is critically important for disease epidemiology. Black flies (Diptera: Simuliidae) are significant hematophagous insects, as many species are pests and vectors that transmit pathogens to humans and other animals. Ecological factors associated with black fly species distribution have been extensively examined for the immature stages but are far less well explored for the adult stage. In this study, we collected a total of 7706 adult black fly specimens from various locations in forests, villages and animal shelters in Thailand. The integration of morphology and DNA barcoding revealed 16 black fly taxa, including Simulium yvonneae, a species first found in Vietnam, which is a new record for Thailand. The most abundant species was the Simulium asakoae complex (n = 5739, 74%), followed by S. chumpornense Takaoka and Kuvangkadilok (n = 1232, 16%). The Simulium asakoae complex was dominant in forest (3786 of 4456; 85%) and village (1774 of 2077; 85%) habitats, while S. chumpornense predominated (857 of 1175; 73%) in animal shelter areas. The Simulium asakoae complex and S. nigrogilvum Summers, which are significant pests and vectors in Thailand, occurred at a wide range of elevations, although the latter species was found mainly in high (>1000 m) mountain areas. Simulium chumpornense, S. nodosum Puri and the S. siamense Takaoka and Suzuki complex occurred predominately in low (1000 m) mountain areas. A host blood meal analysis revealed that the S. asakoae; S. chamlongi Takaoka and Suzuki; S. nigrogilvum; S. chumpornense; and the S. striatum species group were biting humans. This is the first report of the latter two species biting humans. We also found that S. chumpornense was biting turkeys, and S. chamlongi was biting chickens, which are new host blood sources recorded for these species. In addition, we found that the S. feuerborni Edwards complex was biting water buffalo, which is the first report on the biting habits of this species.

Laboratory studies of the numerical response of the predator Cyrtorhinus lividipennis Reuter to its natural prey, Nilaparvata lugens Stal, determined the reproductive response to number of eggs oviposited, prey-dependent birth rate, prey-dependent mortality rate, and life cycle duration to different densities of N. lugens eggs. The experiments were conducted in cages with 1, 5, 10, 15, 20, and 30 eggs/predator per cage with 20 replications. The results indicated that the numerical response of C. lividipennis was positively related to prey density, with greater amounts of eggs laid, a longer duration of the lifespan, and adult age observed at a high prey density than a low prey density. However, the sex ratio and adult longevity were not affected by the prey density. The minimum prey density for completing C. lividipennis development was 5 eggs/d, whereas the minimum number of prey needed to produce an egg was 10 eggs/d. The study of the numerical response provided data for calculating the prey-de...