Large Forest Floor Millipede

Description:

While this looks like Large Forest-floor Millipede, Nyssodesmus python, I'm not absolutely sure it is (see below). There are two here, and they are about 3¾" long engaged in mating activities—the male straddles the female and stays there for some time after mating to make sure no other male fertilizes the eggs. So you're likely to see them this way.

Habitat:

I should probably label it Nyssodesmus sp. because while it is a good match visually, it was spotted on the Pacific slope of the Osa peninsula rather than the Caribbean slope. The habitat was in moist forest, in the debris of a rotting log that had been ripped apart by a herd of collared peccaries.