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The arboreal click beetle fauna (Coleoptera: Elateridae) in a lowland tropical rainforest in southern Venezuela was observed and collected by means of a tower crane for a full year. The evaluation of the elaterid assemblage is part of a general survey of Coleoptera associated with several canopy trees. The Elateridae represented the tenth most species-rich beetle family in the canopy of the crane plot and was therefore selected for a detailed analysis of host-use patterns. In total, 20 species of Elateridae with 402 adult individuals were sampled, including seven singletons. Species were either flower visiting (Aeolus Eschscholtz and Cosmesus Candèze) or fed mainly on extrafloral nectaries (Chalcolepidius Eschscholtz, Crepidius Candèze, Lacon Castelnau, Lissomus Dalman, and Semiotus Eschscholtz). The most abundant species was Aeolus sp. 1 (N = 306) feeding on flowers of nine different host-tree species. This species was found often in high abundances during the entire flowering period of a single tree species with highest abundances coinciding with the maximum of open flowers. Aeolus sp. 1 was recorded almost every month of the year moving usually from one flowering tree species to another comprising possibly the entire local population. This species showed preferences between different tree species and occurred there only at night. Tree species that supported the most species-rich elaterid assemblages were Ruizterania trichanthera (Spruce ex Warm.) Marc.-Berti (Vochysiaceae) (N = 8) and Goupia glabra Aubl. (Goupiaceae) (N = 6). Only one elaterid species with at least two collected individuals was found restricted to one tree species.
The genus Oryctopterus Karny, 1937 (Orthoptera, Stenopelmatidae, Oryctopinae) is reported from India for the first time and two new species, Ot. varuna sp. nov. and Ot. yeshwanthi sp. nov. are described. Male and female external genitalia of Ot. varuna sp. nov. and female genitalia of Ot. yeshwanthi sp. nov. are figured and described. Notes on seasonality, food habits and behavior of Ot. varuna sp. nov. are provided.
Invasive alien American bullfrog populations are commonly identified as a pernicious influence on the survival of native species due to their adaptability, proliferation and consequent ecological impacts through competition and predation. However, it has been difficult to determine conclusively their destructive influence due to the fragmentary and geographically dispersed nature of the historical database. An expanding meta-population of invasive American bullfrogs, Rana catesbeiana (= Lithobates catesbeianus), became established on southern Vancouver Island, British Columbia, Canada in the mid- to late 1980s. An on-going bullfrog control program begun in 2006 offered a unique opportunity to examine the stomach contents removed from 5,075 adult and juvenile bullfrogs collected from 60 sites throughout the active season (April to October). Of 15 classes of organisms identified in the diet, insects were numerically dominant, particularly social wasps and odonates (damselflies and dragonflies). Seasonality and site-specific habitat characteristics influenced prey occurrence and abundance. Native vertebrates in the diet included fish, frogs, salamanders, snakes, lizards, turtles, birds, and mammals, including some of conservation concern. Certain predators of bullfrog tadpoles and juveniles are commonly preyed upon by adult bullfrogs, thereby suppressing their effectiveness as biological checks to bullfrog population growth. Prey species with antipredator defences, such as wasps and sticklebacks, were sometimes eaten in abundance. Many prey species have some type of anti-predator defence, such as wasp stingers or stickleback spines, but there was no indication of conditioned avoidance to any of these. Results from this study reinforce the conclusion that, as an invasive alien, the American bullfrog is an opportunistic and seemingly unspecialized predator that has a uniquely large and complex ecological footprint both above and below the water surface.