List of known Turtle/Tortoise hybrids

[Anja]

TORTOISES
Eastern X Western Hermanns Tortoise (T.h. boettgeri X T.h. hermanni)
Desert Tortoise X Texas Tortoise (Gopherus agassizii x G. berlandieri)

TURTLES
False Map Turtle X Concentric Diamondback Terrapin (G. p. pseudogeographica X M. t. centrata)
Blanding's Turtle  x Wood Turtle (Emydoidea blandingii X Glyptemys insculpta )
Eastern Box Turtle X Three-toed Box Turtle (Terrapene carolina carolina X Terrapene carolina triunguis)
Ornate Box Turtle X Three-toed Box Turtle (Terrapene ornata ornata X Terrapene carolina triunguis)
Peninsula Cooter X Yellow-bellied Slider (Chysemus floridana peninsularis X Trachemys scripta)
Yellow-bellied Slider X Red-eared Slider (Trachemys scripta X Trachemys scripta elegans)

[Terry Allan Hall]

TORTOISES
Eastern X Western Hermanns Tortoise (T.h. boettgeri X T.h. hermanni)
Desert Tortoise X Texas Tortoise (Gopherus agassizii x G. berlandieri)

TURTLES
False Map Turtle X Concentric Diamondback Terrapin (G. p. pseudogeographica X M. t. centrata)
Blanding's Turtle  x Wood Turtle (Emydoidea blandingii X Glyptemys insculpta )
Eastern Box Turtle X Three-toed Box Turtle (Terrapene carolina carolina X Terrapene carolina triunguis)
Ornate Box Turtle X Three-toed Box Turtle (Terrapene ornata ornata X Terrapene carolina triunguis)
Peninsula Cooter X Yellow-bellied Slider (Chysemus floridana peninsularis X Trachemys scripta)
Yellow-bellied Slider X Red-eared Slider (Trachemys scripta X Trachemys scripta elegans)

I knew of a guy here in Texas who, several years ago, produced T.h. hermanni X T. graeca iberia accidently.

For some reason, he euthanized the entire batch, unfortunately...I tried to get him to sell them to me, but he's very "anti-hybrid". 

[Anja]

Oh wow, it would have been interesting to have seen them.