Search Results (5)

Rickettsiae are Gram-negative and obligate intracellular bacteria that cause rickettsioses. These pathogens are typically transmitted by arthropod vectors, such as ticks, mesostigmatid mites, and fleas. Rickettsiae are responsible for many emerging infectious diseases worldwide and are the second most frequently reported cause of non-malarial febrile illnesses in Southeast Asia. However, in Malaysia, studies on the prevalence and distribution of rickettsiae have primarily focused on humans, with limited data on these bacteria in vectors and small mammal hosts. Thus, this study aims to investigate the presence of Rickettsia spp. in small mammals and their associated mesostigmatid mites collected from potential rickettsioses areas in Selangor. Animal trapping was conducted across three different ecological study sites comprising a recreational area, agricultural land, and coastal area. A total of 41 small mammals and 363 mesostigmatid mites were collected and identified. Ten percent of the total individual mites were processed for morphological examination, and the remaining mites were then pooled by hosts, with five individual mites per tube, for DNA extraction. The collected samples, comprising blood, animal tissue, and pooled mites, were subjected to DNA extraction and were screened for Rickettsia spp. via nested polymerase chain reaction (PCR), targeting the citrate synthase-encoding gene (gltA) and outer membrane protein B gene (ompB). Interestingly, two pools (3.33%) of Laelaps spp. recovered from Maxomys whiteheadi and Bandicota indica, collected from a recreational area, tested positive for Rickettsia spp. Sequence analysis and phylogenetic tree of the ompB gene revealed the presence of Rickettsia felis in both laelapid mite pools. To our knowledge, this study provides the first molecular detection of R. felis in Laelaps spp. in Malaysia. Full article

The family Laelapidae (Dermanyssoidea) is morphologically and ecologically the most diverse group of Mesostigmata mites. Although molecular genetic data are widely used in taxonomic identification and phylogenetic analysis, most classifications in Mesostigmata mites are based solely on morphological characteristics. In the present study, eight species of mites from the Laelapidae (Dermanyssoidea) family collected from different species of small rodents in Lithuania, Norway, Slovakia, and the Czech Republic were molecularly characterized using the nuclear (28S ribosomal RNA) and mitochondrial (cytochrome oxidase subunit I gene) markers. Obtained molecular data from 113 specimens of mites were used to discriminate between species and investigate the phylogenetic relationships and genetic diversity among Laelapidae mites from six genera. This study provides new molecular data on Laelaps agilis, Laelaps hilaris, Laelaps jettmari, Haemogamasus nidi, Eulaelaps stabularis, Hyperlaelaps microti, Myonyssus gigas, and Hirstionyssus sp. mites collected from different rodent hosts and geographical regions in Europe. Full article

Landscape diversification with flowering plants can benefit pollinators and natural enemies, although insect pests can also use floral resources for nutrition and chemoprotection. Corn rootworms (Coleoptera: Chrysomelidae, Diabrotica spp.) are major pests of corn (Zea mays L.), and while subterranean larvae primarily feed on corn roots, adult rootworms commonly consume floral resources from other plant species. We quantified the species, density, and sex of adult corn Diabroticite rootworm beetles on wild and cultivated sunflower, corn, and squash, quantified pollen within the bodies of adult northern corn rootworms [NCR, D. barberi (Smith & Lawrence)], and investigated how consumption of sunflower and corn pollen by NCR adults impacted predation of their eggs by two soil-dwelling mites with different feeding specialization. NCR were the most common Diabroticite species on sunflower inflorescences and western corn rootworm (WCR, D. v. virgifera LeConte) were more abundant in corn and squash blossoms. Pollen feeding by NCR adults did not impact egg predation by omnivorous Tyrophagus putrescentiae (Schrank) (Acari: Sarcoptiformes, Acaridae), but predatory Stratiolaelaps scimitus (Womersley) (Acari: Mesostigmata, Laelapidae) ate eggs less frequently and took longer to feed on eggs from NCR females that had fed on sunflower pollen. This research suggests pollen feeding by adult NCR can impact predation of their eggs. While increasing plant diversity can benefit natural enemies and pest control within agroecosystems, it is important to consider how floral resources alter dietary preferences of biocontrol agents. Full article

Predatory soil-dwelling mites, Gaeolaelaps aculeifer (Canestrini) and Stratiolaelaps scimitus (Womersley) (Mesostigmata: Laelapidae), are essential biocontrol agents of small soil arthropod pests. To understand the population characteristics of these two predatory mites, we investigated their development, survival, and fecundity under laboratory conditions. We used Tyrophagus putrescentiae (Schrank) as a food source and analyzed the data using the age-stage, two-sex life table. The duration from egg to adult for G. aculeifer was longer than that for S. scimitus, but larval duration was similar between the two species. Notably, G. aculeifer laid 74.88 eggs/female in 24.50 days, but S. scimitus laid 28.46 eggs/female in 19.1 days. Several population parameters, such as the intrinsic rate of increase, finite rate of increase, net reproductive rate, and gross reproductive rate of G. aculeifer, were significantly higher than those of S. scimitus. Using the bootstrap technique with 100,000 samples, we demonstrated that the life tables constructed based on the 2.5th and 97.5th percentiles of finite rate of increase (λ) net reproductive rate (R₀) may characterize the variability in the survival and fecundity curves, as well as predict population growth uncertainty. These data provide important information for the practical application of predatory soil mites to manage agricultural pests. Full article

Mites should not be overlooked as a forensic tool, as many are commonly associated with decomposing animal matter and are closely associated with specific insect carriers and habitats. It is necessary to increase our understanding of the diversity of mites that are found in human and animal remains, their geographical distribution, and their population dynamics. This work is the first study of the role of mites in forensic science in the Mediterranean region of Navarra (northern Spain). Samples were taken using three types of traps (96 modified McPhail, 96 modified pitfall, and 32 carrion on surface) baited with pig carrion during the period between 11 April and 24 June, 2017. Insects were collected in 100% of the traps and only 27% of them contained mites. Information on 26 species of mites belonging to seven families, their ontogenetic phoretic stage/s, their abundance, and presence/absence during the spring season of the study is given. The most abundant species collected were Macrocheles merdarius, Poecilochirus austroasiaticus, and Poecilochirus subterraneus. We are contributing 16 new records for the Iberian Peninsula: seven species of Parasitidae, three species of Macrochelidae, four species of Eviphididae, one species of Halolaelapidae, and one species of Laelapidae. Full article