The distal tip of the abdomen is not as clear as I'd like in order to say 'yes' that is definitely an ovipositor. From the small hole at the metanotal area, I would say this is a male - and that the hole is the start of the metanotal gland. Therefore, they appear to develop in the 4th instar stage.

This is an awesomely lucky shot...all the markings are visible - including the identifying antennal markings on the scape and pedicel [black dots on bright white field]. Note the black rings on the joints, the rows of white dots on the abdomen, and the black marks on the antennae.