A few years ago, I published an account of long term sperm storage in the Ganges softshell turtle (Nilssonia gangetica), with females producing eggs for 15 years without access to a male. Turtles have seminiferous tubules, which are structures that allow for this incredible "immaculate conception".
Last week, one of our Morolett's crocodile female laid 36 eggs. She had been in isolation since May 2007, since she didn't get along with the breeding group, and was repeatedly attacked by the single male. So we collected the eggs, and found that two of the eggs were banded!!! This is a little over three years of sperm storage in a crocodile, as far as I know only reported in the dwarf caiman (Paleosuchus palpebrosus), and the American alligator (Alligator mississippiensis), although the later don't store sperm for more than a year.
The interesting factor is that female 204 (the Morolett's female of concern), laid clutches in 2007, 2008, and 2009, but none of these eggs were fertile. Anyhow, we are taking very special care of those 2 viable eggs and hope to hatch them, after which we can perhaps tell by blood samples from them, female 204, and the male, whether this is a case of sperm storage or parthenogenesis.
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