Pachistopelma rufonigrum Pocock, 1901 presents ontogenetic changes of its coloration pattern throughout its development. After emergence from the eggs, spiderlings are bluish, with metallic and/or iridescent nuances. The juveniles have a vertically directed black stripe in the central region of abdomen dorsum and three horizontally directed black stripes in the abdomen dorsum. Adults are completely black. These coloration differences between juveniles and adults of the same species appear to be a strategy to avoid the intraspecific competition.
Colors; ontogeny changes; spider; Theraphosidae
