Amphidasya umbrosa was characterized by medium-sized to large (for Amphidasya) leaves with well developed petioles, half or more as long as the elliptic to obovate blades, well developed multi-laciniate stipuoles, narrow calyx lobes 9--15 mm long, and a relatively large coorolla, with the tube 15-35 mm long and the lobes 10-12 mm long. The corolla is also characteristic pften have a funnelform throat and the tip acute in bud. The leaf secondary and tertiary venation is regularly, laxly areolate, and characteristically thickened and puberulous to strigillose-puberulous. 

Amphidasya umbrosa is similar to Amphidasya bullata, was seprated mainly by leaf siz when it was described. Modern specmiens referred to these two species now overlap in this regard, and Amphidasya bullata was described from incomplete material, without flowers, so its identity cannot be fully clarified. This other species wasalso separated by Standley by the bullate leaves with the venation prominent abaxially, but those features now appear to vary also. These are separated provisionally here, with Amphidasya bulltata distinguished by a leaf and petiole from similar to that of Amphidasya umbrosa but closely set, abaxially prominulous, hirtellous to pilosulous leaf venation. These may eventually be found to be conspcific.