I am drawing a blank here.
The central spines on geminispina are stouter and more prominent compared to the radial spines, making them quite distinct. I am seeing 1 or maybe 2 central spines in the photo (hard to tell really) but no dark tips. That would put it in the genus, given the wool and bristles just barely visible in a couple of axils (the part of the stem in between the tubercles). A flower picture might get you closer to the answer, if nobody else has it pinned down.
