RESUMO
Chalcidoidea are mostly parasitoid wasps that include as many as 500 000 estimated species. Capturing phylogenetic signal from such a massive radiation can be daunting. Chalcidoidea is an excellent example of a hyperdiverse group that has remained recalcitrant to phylogenetic resolution. We combined 1007 exons obtained with Anchored Hybrid Enrichment with 1048 ultra-conserved elements (UCEs) for 433 taxa including all extant families, >95% of all subfamilies, and 356 genera chosen to represent the vast diversity of the superfamily. Going back and forth between the molecular results and our collective knowledge of morphology and biology, we detected bias in the analyses that was driven by the saturation of nucleotide data. Our final results are based on a concatenated analysis of the least saturated exons and UCE datasets (2054 loci, 284 106 sites). Our analyses support an expected sister relationship with Mymarommatoidea. Seven previously recognized families were not monophyletic, so support for a new classification is discussed. Natural history in some cases would appear to be more informative than morphology, as illustrated by the elucidation of a clade of plant gall associates and a clade of taxa with planidial first-instar larvae. The phylogeny suggests a transition from smaller soft-bodied wasps to larger and more heavily sclerotized wasps, with egg parasitism as potentially ancestral for the entire superfamily. Deep divergences in Chalcidoidea coincide with an increase in insect families in the fossil record, and an early shift to phytophagy corresponds with the beginning of the "Angiosperm Terrestrial Revolution". Our dating analyses suggest a middle Jurassic origin of 174 Ma (167.3-180.5 Ma) and a crown age of 162.2 Ma (153.9-169.8 Ma) for Chalcidoidea. During the Cretaceous, Chalcidoidea may have undergone a rapid radiation in southern Gondwana with subsequent dispersals to the Northern Hemisphere. This scenario is discussed with regard to knowledge about the host taxa of chalcid wasps, their fossil record and Earth's palaeogeographic history.
Assuntos
Parasitos , Vespas , Animais , Vespas/genética , Filogenia , Evolução BiológicaRESUMO
Anagyrus callidus Triapitsyn, Andreason Perring (Hymenoptera: Encyrtidae), recently described from southern California, USA and Mexico, is a primary parasitoid of the pink hibiscus mealybug, Maconellicoccus hirsutus (Green) (Hemiptera: Pseudococcidae). This wasp species previously was misidentified as Anagyrus kamali Moursi, which was introduced and released as such in the United States (California and Florida) and Mexico. In this paper, the origin of A. callidus is shown to be from Taiwan, based on differences in the morphology and molecular sequences of voucher specimens of an earlier colony of the misidentified A. kamali from Puerto Rico (released in August 2002 in southern Florida), and specimens that originated in southern Taiwan.
Assuntos
Hemípteros , Himenópteros , Animais , California , Florida , Hibiscus , México , Porto Rico , TaiwanRESUMO
Viruses are ubiquitous within all habitats that support cellular life and represent the most important emerging infectious diseases of plants. Despite this, it is only recently that we have begun to describe the ecological roles of plant viruses in unmanaged systems and the influence of ecosystem properties on virus evolution. We now know that wild plants frequently harbor infections by diverse virus species, but much remains to be learned about how viruses influence host traits and how hosts influence virus evolution and vector interactions. To identify knowledge gaps and suggest avenues for alleviating research deficits, we performed a quantitative synthesis of a representative sample of virus ecology literature, developed criteria for expanding the suite of pathosystems serving as models, and applied these criteria through a case study. We found significant gaps in the types of ecological systems studied, which merit more attention. In particular, there is a strong need for a greater diversity of logistically tractable, wild dicot perennial study systems suitable for experimental manipulations of infection status. Based on criteria developed from our quantitative synthesis, we evaluated three California native dicot perennials typically found in Mediterranean-climate plant communities as candidate models: Cucurbita foetidissima (buffalo gourd), Cucurbita palmata (coyote gourd), and Datura wrightii (sacred thorn-apple). We used Illumina sequencing and network analyses to characterize viromes and viral links among species, using samples taken from multiple individuals at two different reserves. We also compared our Illumina workflow with targeted RT-PCR detection assays of varying costs. To make this process accessible to ecologists looking to incorporate virology into existing studies, we describe our approach in detail and discuss advantages and challenges of different protocols. We also provide a bioinformatics workflow based on open-access tools with graphical user interfaces. Our study provides evidence that dicot perennials in xeric habitats support multiple, asymptomatic infections by viruses known to be pathogenic in related crop hosts. Quantifying the impacts of these interactions on plant performance and virus epidemiology in our logistically tractable host systems will provide fundamental information about plant virus ecology outside of crop environments.
RESUMO
Twenty-nine species are recognized in the Orasema stramineipes species group, including 22 new species in what is now the most diverse species group of the New World ant-parasitoid genus Orasema Cameron. Orasema aenea Gahan syn. n. is synonymized with O. freychei (Gemignani), the holotype of which has been rediscovered. Orasema smithi Howard syn. n. is synonymized with Orasema minutissima Howard. Orasema violacea Gemignani syn. n. and its replacement name Orasema gemignanii De Santis syn. n. are synonymized with O. worcesteri (Girault). Twenty-two species are described as new: O. arimbome Dominguez, Heraty Burks n. sp., O. carchi Heraty, Burks Dominguez n. sp., and the following 20 species by Burks, Heraty Dominguez: O. chunpi n. sp., O. cozamalotl n. sp., O. evansi n. sp., O. hyarimai n. sp., O. kaspi n. sp., O. kulli n. sp., O. llanthu n. sp., O. llika n. sp., O. mati n. sp., O. nyamo n. sp., O. pirca n. sp., O. pisi n. sp., O. qillu n. sp., O. qincha n. sp., O. rikra n. sp., O. taku n. sp., O. tapi n. sp., O. torrensi n. sp., O. woolleyi n. sp., and O. yaax n. sp. The stramineipes-group has much greater diversity in tropical America than outside the tropics, and is much more diverse than its sister-group, the susanae-group, which is mainly present in temperate regions of Argentina. A hypothesis of phylogenetic relationships is proposed based on an analysis of 28S-D2 rDNA and cytochrome oxidase I (COI) for 14 stramineipes-group species. Species concepts were established using both morphological and molecular data. Most species in the stramineipes-group have a tropical distribution, with only a few species in temperate regions. Ant hosts for the group include Pheidole Westwood, Wasmannia Forel, and possibly Solenopsis Westwood (Formicidae: Myrmicinae). Orasema minutissima is a common parasitoid of Wasmannia auropunctata Roger in the Caribbean and has the potential to be a biological control agent in other areas of the world. Two distinct size morphs are recognized for O. minutissima, which are correlated with attacking either Wasmannia (small morph) or different castes of Pheidole (medium to large size morphs). Some species of Orasema have been regarded as pests due to scarring or secondary infections of leaves or fruit of banana, yerba mate or blueberry, but outbreaks are rare and the threat is usually temporary.