From the Great Lakes region to New England and up into Canada hybrid Ambystoma salamanders occur. Four species are involved in this hybridization complex: Jefferson salamander (Ambystoma jeffersonianum), blue-spotted salamander (Ambystoma laterale), smallmouth salamander (Ambystoma texanum), and eastern tiger salamander (Ambystoma tigrinum). These species have hybridized into several interesting forms that are entirely female and usually polyploid, meaning they have more chromosome sets than the standard diploid (2 sets). Hybrids can exist with genetic material from three of the four species. Individuals can be triploid (3 sets of chromosomes), tetraploid (4 sets), and even pentaploid (5 sets). Leer más.