Project description:Termites effectively feed on many types of lignocellulose assisted by their gut microbial symbionts. To better understand the microbial decomposition of biomass with varied chemical profiles, it is important to determine whether termites harbor different microbial symbionts with specialized functionalities geared toward different feeding regimens. In this study, we compared the microbiota in the hindgut paunch of Amitermes wheeleri collected from cow dung and Nasutitermes corniger feeding on sound wood by 16S rRNA pyrotag, comparative metagenomic and metatranscriptomic analyses. We found that Firmicutes and Spirochaetes were the most abundant phyla in A. wheeleri, in contrast to N. corniger where Spirochaetes and Fibrobacteres dominated. Despite this community divergence, a convergence was observed for functions essential to termite biology including hydrolytic enzymes, homoacetogenesis and cell motility and chemotaxis. Overrepresented functions in A. wheeleri relative to N. corniger microbiota included hemicellulose breakdown and fixed-nitrogen utilization. By contrast, glycoside hydrolases attacking celluloses and nitrogen fixation genes were overrepresented in N. corniger microbiota. These observations are consistent with dietary differences in carbohydrate composition and nutrient contents, but may also reflect the phylogenetic difference between the hosts.
Project description:The phyline plant bug genus Tytthus Fieber, previously containing 19 species, is revised. Isoproba Osborn and Drake, 1915, incorrectly placed in the subfamily Bryocorinae, tribe Dicyphini, is synonymized as a junior synonym of Tytthus Fieber, syn. n.; the only included species, Isoproba picea Osborn and Drake is transferred to Tytthus, comb. n., as the senior synonym of Tytthus hondurensis Carvalho, syn. n.; and Tytthus koreanus Josifov and Kerzhner, 1972 is synonymized with Tytthus chinensis (Stål 1860), syn. n.; and a lectotype for Tytthus parviceps is designated. The six new species Tytthus femoralis from Cuba, Ecuador, Guatemala, Jamaica, Mexico, and Peru,Tytthus fuscicornis from New Mexico (USA), Tytthus mexicanus from Mexico, Tytthus pallidus from Brazil and Panama, Tytthus uniformis from Arizona and New Mexico (USA), and Tytthus wheeleri from the eastern United States are described, bringing the total number of species for the genus to 24. A color adult habitus illustration of Tytthus wheeleri, color photographs for each species (except Tytthus juturnaiba Carvalho and Wallerstein), illustrations of male genitalia, scanning electron photomicrographs of selected structures of certain species, and an identification key are provided to facilitate species recognition. A phylogenetic analysis is offered to help infer relationships.
Project description:Eusocial animals, such as the termites, often build a nest-like structure called a mound that provides shelter with stable internal conditions and protection against predators. Termites are important components of the Brazilian Cerrado biota. This study aimed to investigate the bacterial community composition and diversity of the Syntermes wheeleri termite-mound soil using culture-independent approaches. We considered the vertical profile by comparing two different mound depths (mound surface and 60 cm) and seasonality with samplings during the rainy and dry seasons. We compared the mound soil microbiota to the adjacent soil without the influence of the mound to test the hypothesis that the Cerrado soil bacterial community was more diverse and more susceptible to seasonality than the mound soil microbiota. The results support the hypothesis that the Cerrado soil bacterial community is more diverse than the mound soil and also has a higher variability among seasons. The number of observed OTUs (Operational Taxonomic Units) was used to express bacterial richness, and it indicates that soil moisture has an effect on the community distribution and richness of the Cerrado samples in comparison to mound samples, which remain stable across seasons. This could be a consequence of the protective role of the mound for the termite colony. The overall community taxonomic profile was similar between soil samples, especially when compared to the taxonomic composition of the Syntermes wheeleri termite's gut, which might be explained by the different characteristics and functionality between the soil and the gut microbial community.
Project description:Understanding the earliest events in speciation remains a major challenge in evolutionary biology. Thus identifying species whose populations are beginning to diverge can provide useful systems to study the process of speciation. Drosophila aldrichi, a cactophilic fruit fly species with a broad distribution in North America, has long been assumed to be a single species owing to its morphological uniformity. While previous reports either of genetic divergence or reproductive isolation among different D. aldrichi strains have hinted at the existence of cryptic species, the evolutionary relationships of this species across its range have not been thoroughly investigated. Here we show that D. aldrichi actually is paraphyletic with respect to its closest relative, Drosophila wheeleri, and that divergent D. aldrichi lineages show complete hybrid male sterility when crossed. Our data support the interpretation that there are at least two species of D. aldrichi, making these flies particularly attractive for studies of speciation in an ecological and geographical context.
Project description:Darkling beetle larvae (Coleoptera, Tenebrionidae) are collectively referred to as false wireworms. Larvae from several species in the genus Eleodes are considered to be agricultural pests, though relatively little work has been done to associate larvae with adults of the same species and only a handful of species have been characterized in their larval state. Morphological characters from late instar larvae were examined and coded to produce a matrix in the server-based content management system mx. The resulting morphology matrix was used to produce larval species descriptions, reconstruct a phylogeny, and build a key to the species included in the matrix. Larvae are described for the first time for the following 12 species: Eleodes anthracinus Blaisdell, Eleodes carbonarius (Say), Eleodes caudiferus LeConte, Eleodes extricatus (Say), Eleodes goryi Solier, Eleodes hispilabris (Say), Eleodes nigropilosus LeConte, Eleodes pilosus Horn, Eleodes subnitens LeConte, Eleodes tenuipes Casey, Eleodes tribulus Thomas, and Eleodes wheeleri Aalbu, Smith & Triplehorn. The larval stage of Eleodes armatus LeConte is redescribed with additional characters to differentiate it from the newly described congeneric larvae.
Project description:The genus Enderleiniella Becker, 1912 is revised. The genus is distinguished on the basis of a somewhat flattened head with the inner vertical setae located anteromedially to the outer vertical setae, three lightly incised lines on the scutum, trapezoidal or rectangular scutellum with marginal setae borne on tubercles, reduced alula and anal angle of the wing, and the structure of the male genitalia. The genus contains eleven species in the northern Neotropical and southern Nearctic Regions: E. caerulea sp. nov. (type locality: Blue Creek, Belize); E. cryptica sp. nov. (type locality: 24 km W Piedras Blancas, Costa Rica); E. flavida sp. nov. (type locality: Emerald Pool, Dominica); E. longiventris (Enderlein, 1911) (type species; type locality: Costa Rica); E. maculata sp. nov. (type locality: Xilitla, San Luis Potosi, Mexico); E. marshalli sp. nov. (type locality: Guanacaste, Costa Rica); E. maya sp. nov. (type locality: Las Escobas, Guatemala); E. punctata sp. nov. (type locality: Potrerillo, Bolivia); E. tripunctata (Becker, 1916) (type locality: San Mateo, Costa Rica); E. tumescens sp. nov. (type locality: San Esteban, Venezuela); and E. wheeleri sp. nov. (type locality: Turrialba, Costa Rica).