There are lots of trichocereus/echinopsis cacti that look very similar to one another, and that is why there is a lot of confusion in the taxonomy of trichocereus cacti. The number of ribs, spines, the spines color and length, and more, are ways to classify the cacti, but SWIM
isn't an expert. Perhaps providing photos of the cacti in question will allow some of the more experienced members to identify the species/strains. Also, what do you mean by round? San Pedro
and other trichocereus tend to be columnar cacti, while the shorter round cacti, can be lophophora (peyote
) or another number of species.