First report of the destroyer ant Trichomyrmex destructor (Jerdon, 1851) (Hymenoptera, Formicidae, Myrmicinae) as a pest of red dragon fruit Selenicereus costaricensis (Cactaceae): a case of extrafloral nectaries, evolved for self-defense, ended up becoming a source of harm to the plant

Abstract

The destroyer ant, Trichomyrmex destructor (Jerdon, 1805) (Formicidae, Myrmicinae), is newly reported as a pest of the red dragon fruit Selenicereus costaricensis (F. A. C. Weber) S. Arias & N. Korotkova ex Hammel (Cactaceae). It feeds on the areoles, scale leaves and surrounding green tissues at the base of spines of S. costaricensis, due to the presence of extrafloral nectaries. The damaged portions turned yellow and then dark brown to black. The extent of infestation on the cladode was 0–50%. Besides cladode, flowers and fruits were also damaged. Up to 90% fruits and/flowers were infested on four clumps. This is a case of direct cost of production of extrafloral nectaries, which are protective in function against herbivores. This is the first report of extrafloral nectaries in S. costaracensis.