The little hybrid crayfish have grown - will they be reproductive?

In October 2009 we had started a breeding experiment between the two presumed species of Austropotamobius pallipes complex under controlled conditions, in order to investigate the possible existence of reproductive barriers. In June 2010 offsprings did hatch, either from females having intraspecific or interspecific (only italicus females) mating. The mating success of A. pallipes complex showed no reproductive barrier and the isolation mentioned in previous researches does not work at pre-zygotic level. As regards post-zygotic isolation, italicus hybrid zygotes were formed and successfully developed in three months post-hatching period (Ghia et al., 2011). Three years have passed and nowadays 12 of those hybrid crayfish are still alive. We describe their story through regular checks; we discuss their growth trend according to water temperature data recorded over the three-years period; male maturity and the occurrence of the glair glands in females; and their morphometric features compared to the origin natural populations.