Unusual behavior of oviposition and development of <Emphasis Type="Italic">Sitophilus zeamais</Emphasis> (Coleoptera: Curculionidae) in peach and apple fruits

The maize weevil Sitophilus zeamais Motschulsky, 1855 (Coleoptera: Curculionidae) is a worldwide pest on stored products, as maize, wheat and rice grains. However, in South Brazil, these weevils have been found attacking fruits in field conditions. It was reported that adults attack fruits to feeding, but there was no information of oviposition and larval development on these hosts. Furthermore, due to monitoring apple orchards, was observed that some fruits showed distinct kind of punctures, suggesting a oviposition by these weevils. The present study reports first record an unusual behavior of S. zeamais by oviposition and larval development in peach and apple fruits. The study was conducted in laboratory conditions (temperature: 25?±?1 °C, RH: 70?±?10% and photophase of 14 h). Peach and apple fruits were offered to S. zeamais females. The oviposition and duration of immature stages in peach were measured in fruits and in corn grains, used as control observation. The oviposition and larval development occurred in peach and apple fruits, with a development until to adult. The average of egg-to-adult was 47.4 d in peach and and 45.1 d apple fruits, respectively, while in corn grains, its natural host, the duration was 38.2 d. These results show that the damage caused by S. zeamais in peach and apple fruits may be due to oviposition and the development of immature stages. So, the novelty is in demonstrating that the maize weevil does not just feed as an adult opportunistically on the fruits, but can complete a full life cycle using fresh fruits.     

Linking fish ecomorphotypes to food categories and local-scale habitat uses along a Brazilian coastal stream

Fish ecomorphological analyses often deal with several traits simultaneously, making it challenging to interpret general patterns, and have not addressed the longitudinal component of streams in morphology-habitat relationships. We identified ecomorphotypes of fishes and correlated their morphological variation with food, structural/hydrological variables, and abundances to detect their links with diet and local-scale habitat categories. Eighteen morphometric traits were obtained from specimens collected by electrofishing in a coastal Atlantic stream in Brazil. To test for morphology-habitat associations, headwaters, middle, and mouth reaches were divided into shorter sampling sites, with the middle reach being classified into riffle, run, and pool mesohabitats. Multivariate analyses highlighted the morphological variations and associated the form categories of 18 fish species with food and habitat categories. It resulted in four combined trophic and habitat ecomorphotypes: (1) benthic AB/lithophilic, composed of smaller to longer loricariids, detritivores, of fast-water, and pebbly habitats; (2) benthic C/lithophilic of very fast-waters, algal and detritus scrapers, with longer intestines than the other benthic species, wider suctorial mouths, inhabitants of headwaters, and riffles habitats; (3) nektobenthic/lithophilic with streamlined bodies, invertebrate feeders, and dwellers of faster-water, cobbly habitats; and (4) nektonic/limnophilic composed mainly by characins, which had strong correlations with terrestrial insect consumption, and lentic/pool, sandy habitats. The morphology–environment correlations linked these ecomorphotypes to the broad habitat gradient arrayed in longitudinal and local scales. These results permit inferring the larger form patterns expected for local fish assemblages and emphasise the fish trait categorisation as a possible surrogate to reveal broader ecomorphological associations.