Carabid beetles (Coleoptera: Carabidae) of temporally inundated and non-flooded upland lowland forest in the Ecuadorian Amazon

The majority of invertebrate species inhabiting Neotropical rainforests remain undiscovered or inadequately described. To grasp potential biodiversity loss within the megadiverse, Yasuní region (eastern Ecuador), it is critical to acquire ecological and taxonomic data of invertebrate fauna.

Our study examined differences in diversity and community composition of understory-dwelling carabid beetles (Coleoptera: Carabidae, Excluding Cicindelini) of temporally inundated and non-inundated lowland rainforest. Inundation events from an adjacent mixed-water river may lead to higher diversity and generate unique communities compared to upland forests.

Two collection methods were employed: flight intercept traps (FITs) and night hand collections. Differences between techniques were analyzed among forest types.  For finer spatial analyses, the two forest types were divided into primary and secondary floodplain and sloping and ridge upland. Sampling occurred June and July, 2011 and 2012 with an additional FIT collecting period in October-November, 2011. Three or four systematic hand collections were conducted and six FITs were erected within the four forest types.

A total of 815 individuals, representing 143 morphospecies, were collected. Richness and Shannon diversity were similar among forest types but species compositions differed. FITs and hand collection techniques vary in efficiency depending on forest type and carabid taxa. In terms of number of individuals, hand sampling in general was more effective, especially for sampling inundation forests, although FITs were more efficient in upland forest. For lowland rainforests of western Amazonia inundated and non-inundated sites maintain significantly different carabid communities.