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BIODIVERSITY, GRASSHOPPER behavior, BIOMES, PHYLOGENY, and SPECIES distribution

Abstract: The open vegetation biomes, within the limits of the Chacoan subregion, occur along a diagonal in eastern South America covering a large range of environmental conditions. In order to contribute to the knowledge on the biodiversity of these open biomes, we analysed the phylogenetic relationships of the grasshopper genus Zoniopoda to the remaining South American Romaleinae, and examined the biogeographical patterns of diversification of the genus. The study is based on morphological and molecular (COI and H3) evidence, including 12 species of Zoniopoda and 17 species of four tribes of South American Romaleinae. We describe a new species of Zoniopoda, and test its taxonomic placement within the group. Results of our phylogenetic analyses recovered Zoniopoda as a monophyletic group with high support values. According to the dispersion–vicariance analysis, the ancestor of Zoniopoda may have been distributed in an area corresponding to the Chacoan and Cerrado provinces. A vicariant event, that could be explained by the uplift of the Brazilian Plateau and the subsidence of the Chaco, is hypothesized to have occurred splitting the ancestral distribution of Zoniopoda, resulting in the independent evolution of the Tarsata group within the Cerrado and the Iheringi group in the Chacoan subregion. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:act:FCFB4C5D-1741-46F1-8E25-B37ED2B9D872. [ABSTRACT FROM AUTHOR]

BIODIVERSITY, VERTEBRATES, HABITATS, GLACIATION, and PLIOCENE Epoch

It is now rare to find a semi-aquatic organism group with which to vigorously test whether their diversification model and distribution pattern are closely related to the Cenozoic temperature variation. This hypothesis is explored for water striders of the genera Aquarius Schellenberg, Gerris Fabricius and Limnoporus Stål, which comprise a monophyletic clade with primarily Holarctic distribution. We sample almost 90% of the currently recognized Aquarius, Gerris and Limnoporus species. Five DNA fragments from 62 species are used to reconstruct a phylogram. Divergence time is estimated using Bayesian relaxed-clock method and three fossil calibrations. We investigate diversification dynamics, biogeography and ancestral state reconstruction by using maximum-likelihood, Bayesian and parsimony approaches. Our results showed that the crown of the three genera originated and underwent an initial diversification in Asia at 72 Ma (HPD: 59-86 Ma) in the Late Cretaceous, subsequently expanding into other regions via dispersal. The Bering Land Bridge was the major migration route between Eurasia and North America but was interrupted before the early Oligocene (34 Ma). Ancestors most likely used lentic habitats, and a minimum of two independent shifts to lotic habitats occurred in the initial diversification. Cenozoic temperature variation regulated the evolutionary history of Holarctic water striders of the genera Aquarius, Gerris and Limnoporus. Temperature warming during Stage I (52-66 Ma) was associated with the disappearance of shallow lentic habitats; this phenomenon forced certain lentic lineages to colonize new lotic habitats and promoted the diversification of lineages. Temperature cooling during Stage II (after 34 Ma) was associated with the fragmentation of water habitats of the 'mixed-mesophytic' belt, resulting in the extinction of historical taxa and influencing close lineages that shaped the present disjunct Eurasian-North American distribution. [ABSTRACT FROM AUTHOR]

PHYLOGENY, MORPHOGENESIS, EVOLUTIONARY developmental biology, ORGANISMS, MICROBIAL ecology, and TAXONOMY

Robust phylogenetic hypotheses have become key for studies addressing the evolutionary biology and ecology of various groups of organisms. In the species-rich heteropteran superfamily Pentatomoidea, phylogenies at lower taxonomic levels are still scarce and mostly employ exclusively morphological data. In this study, we conducted a total evidence phylogeny focusing on the tribe Carpocorini (Pentatomidae), using morphological data and four DNA markers ( COI, Cytb, 16S and 28S rDNA; ∼2330 bp; 32 taxa) in order to investigate the relationships within Euschistus Dallas, one of the most speciose pentatomid genera, and between Euschistus and related genera. Our hypotheses generated by maximum likelihood and Bayesian inference show that the current taxonomic composition and classification of Euschistus and allied genera are in need of revision. Euschistus was recovered as nonmonophyletic, with the subgenera forming four independent lineages: Euschistus ( Euschistus) and Euschistus ( Lycipta) Stål are sister groups; Euschistus ( Euschistomorphus) Jensen-Haarup is more closely related to Dichelops Spinola and Agroecus Dallas; and Mitripus Rolston is divided into two clades closely related to Sibaria Stål and Ladeaschistus Rolston. We chose not to change the classification of E. ( Euschistomorphus) until further data become available, and propose to split Euschistus into three genera with the exclusion of Euschistus ( Mitripus) and all of its species. Here we elevate Mitripus to genus rank to include M. acutus comb.n., M. convergens comb.n. and M. legionarius comb.n., and propose Adustonotus Bianchi gen.n. to include A. anticus comb.n., A. latus comb.n., A. tauricornis comb.n., A. grandis comb.n., A. hansi comb.n., A. paranticus comb.n., A. irroratus comb.n. and A. saramagoi comb.n. We also provide identification keys to the genera Adustonotus gen.n., Ladeaschistus, Mitripus n. rank and Sibaria, here defined as the Mitripus genus group, and to the species of Mitripus and Adustonotus gen.n. Our results provide insights into the current status of the classification of the Pentatomidae, suggesting the need for phylogenetic analyses at different taxonomic levels within stink bugs. This published work has been registered in ZooBank, . [ABSTRACT FROM AUTHOR]