The inner layer of the glomerulus, within the basement membrane surrounding the glomerular capillaries. [ https://sourceforge.net/p/obo/foundational-model-of-anatomy-fma-requests/13/ http://en.wikipedia.org/wiki/Mesangium ]
WP considers this the same as glomerular mesangium. In MA, glomerular and extraglomerular are distingsuished. FMA class has no definition and is a type of stroma, which is inconsistent with our classification of this here.