Siamosaurus is more likely than not a dubious genus of spinosaurid, only known from teeth. it is also the first and only one of two known spinosaurids from Asia (the other being Icthyovenator, found in 2012). The size is unknown, but it may have been about 30 feet long. It was from the Early Cretaceous and was found in Thailand. It was probably a piscivore. What’s interesting is that it was found in 2010 that spinosaurid bone oxygen isotope ratios indicate that they were all semiaquatic, close to that of turtles and crocodilians. Siamosaurus had the largest difference from other theropods, making it probably the most aquatic of all; Spinosaurus had the least difference and probably was not as aquatic as other spinosaurids. This allowed spinosaurids to coexist with other large theropods, giving them a different ecological niche to fill.