Advances in the knowledge of the feeding ecology of Nyctelia circumundata Lesne (Coleoptera: Tenebrionidae) in northeastern Patagonia

CHELI GERMAN HORACIO; BISIGATO ALEJANDRO; MARTINEZ FERNANDO; MARTÍNEZ ROMÁN N; SAÍN CLAUDIA; CAMPANELLA M VICTORIA; FLORES GUSTAVO E.

Mendoza

Simposio; IV International Symposium on Tenebrionoidea; 2015

CCT MENDOZA-CONICET

Tenebrionidae is the most abundant coleopteran family inhabiting the northeastern Patagonia and Nyctelia circumundata Lesne is one of the most conspicuous darklingbeetles in the region. Tenebrionids are typically considered asscavengers, nevertheless there are records of some species feeding on livingplants. In this contribution, usinglaboratory bioassays (two-way choice tests), the feeding ecology of N.circumundata is studied asking the following questions: this beetle feedson living plants? If it is true, it exhibits any feeding preference pattern? It would be ablethat this beetle consumes any invasive specie? Plant water stress could affectthe food selectivity of this beetle? How chemical and physical plant attributesinfluence the foodselection process? As aresult N. circumundata feeds on livingplant and exhibited a defined feeding preference pattern. Evenconsuming the invasive specie Diplotaxistenuifolia (L.) DC., which has turned out to be the most consumed item. N. circumundatadid not show preference byany water supply regimes. These results suggest that the classicalfeeding concept about tenebrionids would be modified. The preference patternobserved could be consequence of a complex interaction between plant energeticattributes, palatability and metabolic requirements. Probably the foodselection process would be a hierarchical process where chemical attributes aretaken into account for species selection and physical attributes for choosingindividuals inside species. The fact that D.tenuifolia was a preferred item suggests the development of new interactionsamong native insects and invasive plants, which may bring about new ecological implications.