[1] Drepanaspis are assumed to have lived primarily in marine environments and is most commonly characterized by their ray-like, heavily armoured bodies, along with their lack of paired fins and jaws.

[1] More specimens of Drepanaspis would later be uncovered in 2004, in the Lower Devonian subdivision of the Ardenne Massif in Belgium and Luxembourg, specifically within the Emsian Oesling, by Alain Bleick and his team.

[1] Previously, the method of using specific arrangements of the lateral line sensory canals to identify the well characterized cyathaspidid and pteraspidid species[5][6] were applied to psammosteids, but proved not to be useful.

[9][7] It is important to note, however, that when the identification of radial ridges of dorsal and ventral plates of D. gemuendenensis as sensory line canals were made by W. Gross in 1963, it sparked some debate from paleontologists Obruchev and Halstead Tarlo.

[12] The presence of widely spaced eyes, sensory canals, and its flattened morphology suggests that these fish may have been bottom feeders that foraged the ocean floor for food.

[9][1] Although these v-shaped tubercles are a distinct characteristic of Drepanaspis, a similar feature have been observed in other psammostean shields, indicating that this genus may have been the ancestor to the giant, meter long and wide psammosteid heterostracans of the Late Devonian.

This complex network of closed canals within the dermal plates is thought to be a derived trait known in very few Psammosteids and are characteristically symmetrical in arrangement, often leading to the surface by pores.

[7] These sensory organs, when found in extant species of fish, are tubes and canals rich in neuromasts shown to be important in detecting changes in water pressure and movement, along with influencing some of their behavioral patterns.

[15] It can be seen in specimens, such as the one discovered from the Odenspiel quarry in Rhineland, Germany, that the lateral line sensory system lies under the dorsal plate of Drepanaspis, situated above its smooth and extremely thin basal layer.

[18] Arandaspida Eroptychiida Traquairaspidiformes Pteraspidiformes Pteraspidina Doryaspis Protaspidoidea Psammosteida Drepanaspididae Drepanaspis D. gemuendenensis D. sehrieli D. lipperti D. jaegeri D. earteri D. edwardsi