This species is characterized by its robust habit, leaves, and inflorescences, pedunculate lax inflorescences branched to 2--4 orders, spiciform axes without any calycophylls, quite small 5-merous flowers, corolla tubes ca. 1.5 mm long and barbate in the upper part of the tube, exserted stamens borne on well developed filaments, shortly exserted stigmas, and obovoid capsules that dehisce through the apical disk portion. The capsules are septicidal then loculicidal. The identity of this species is not entirely clear, but it is documented by both flowers and fruits. Bathysa multiflora has been considered to correspond to the Andean species that has been treated as Bathysa australis (now called Elaeagia mollis, but more detailed study shows it is distinct from that species in its slender, lax, often whorled inflorescence axes, flowers borne in subsessile glomerulous distributed along the spiciform axes, and capsules dehiscent mainly through the disk portion. This species is known only from Satipo in Junín in central Peru, an area still not well known floristically. Another species from that area, Palicourea tunquiensis, was collected in that region in the mid-20th century but not identified until the species was further documented by more modern collections, and is still only known from that region. Bathysa multiflora may have a similar range.