The mysterious tachinid Phyllaristomyia fiebrigi Townsend and new distribution records

Abstract

Last November, while conducting entomological field work in the Corrientes province of Argentina for the Rincón Santa María Grassland Restoration Project, I encountered an unusual tachinid. Its striking coloration was unlike anything I had seen before in a tachinid: the head was yellow, the thorax and abdomen yellow and black, and the wing was reddish-orange at its base and smoky black on the rest. The peculiar antenna, with a leaf-like arista arising from a long and slender postpedicel, was more noticeable later when the specimen was examined in the lab. This fly had landed on my backpack, which I had placed on the ground during my field work. The fly was calm, walking slowly around and not attempting to fly off the way most insects do when approached. On the contrary, even when a jar was placed over it there were no sudden change in behavior and it simply tried to climb the walls, without success. This tranquility allowed us to take pictures of it while it was walking on leaves placed in the jar (Figs. 1–2).