ABSTRACT
Lorryia (Tydeinae) species are commonly found in surveys of rubber trees (Hevea brasiliensis) in Brazil, although only Lorryia formosa (Cooreman, 1958) has been formally reported from this host. In this study, we described Lorryia parvireticuli sp. nov., L. amazonensis sp. nov., L. fortistriata sp. nov., and L. virga sp. nov., associated with rubber trees from Brazil.
Subject(s)
Hevea/parasitology , Mites/classification , Animal Distribution , Animal Structures/anatomy & histology , Animal Structures/growth & development , Animals , Body Size , Brazil , Female , Male , Mites/anatomy & histology , Mites/growth & development , Organ SizeABSTRACT
Island biogeography and metacommunity theory often use equilibrium assumptions to predict local diversity, yet nonequilibrium dynamics are common in nature. In nonequilibrium communities, local diversity fluctuates through time as the relative importance of colonization and extinction change. Here, we test the prevalence and causes of nonequilibrium dynamics in metacommunities of mites associated with rubber trees distributed over large spatial (>1,000 km) and temporal (>30-60 generations) scales in Brazil. We measured colonization and extinction rates to test species turnover and nonequilibrium dynamics over a growing season. Mite metacommunities exhibited nonequilibrium dynamics for most months of the year, and these dynamics tracked climatic conditions. Monthly shifts in temperature of more than 1°C resulted in nonequilibrium dynamics, as did mean temperatures outside of two critical ranges. Nonequilibrium dynamics were caused by a change in colonization with temperature change and changes in both colonization and extinction with absolute temperature. Species turnover showed different trends; high relative humidity increased both colonization and extinction rates, increasing turnover but not nonequilibrium dynamics. Our study illustrates that testing nonequilibrium dynamics can provide new insights into the drivers of colonization, extinction, and diversity fluctuations in metacommunities.
Subject(s)
Demography , Ecosystem , Extinction, Biological , Mites/physiology , Animal Distribution , Animals , Biodiversity , Brazil , Climate , Hevea , Models, Theoretical , Population DynamicsABSTRACT
The current study describes the results of a survey of Phytoseiidae mites conducted on a rubber tree plantation in the State of Bahia, Brazil. We present 22 species, two of which are new to science, Amblydromalus insolitus n. sp. Nuvoloni & Lofego, and Typhlodromips paramilus n. sp. Nuvoloni & Lofego, and three new records for this host are presented. The species composition was more related with the records of the northern Brazilian Region, than with that of Southeastern and Midwestern.
Subject(s)
Asteraceae/parasitology , Mites/classification , Animal Distribution , Animal Structures/anatomy & histology , Animal Structures/growth & development , Animals , Body Size , Brazil , Ecosystem , Female , Male , Mites/anatomy & histology , Mites/growth & development , Organ SizeABSTRACT
Hirsutella thompsonii (Fischer) (Ascomycota: Ophiocordycipitaceae), a fungal pathogen, often causes high mortality in populations of Calacarus heveae Feres (Acari: Eriophyidae), an important pest mite in rubber tree plantations (Hevea brasiliensis Muell. Arg., Euphorbiaceae). However, the ecological and climatic factors regulating this host-pathogen system are poorly known. We compared fungal infections in agroforestry and traditional rubber plantations to evaluate the role of native vegetation and climatic factors on infection rates of C. heveae by H. thompsonii. While the prevalence of H. thompsonii was higher in managed rubber tree plantations, the abundance of C. heveae was about three times higher in traditional plantations. Abundance of C. heveae, agroecosystem management type and microclimatic variables were responsible for driving the infection rates of H. thompsonii. Native vegetation was a source for H. thompsonii and also modified the crop's microclimate, which contributed to its maintenance in the crop fields. Therefore, appropriate management practices may enhance the effects of entomopathogens on conservative biological control of pest mites in agroforestry systems.