This HiRISE image shows modified barchan dunes with shapes that resemble “raptor claws.” The unusual morphology of these dunes suggests a limited supply of windblown sand.
Winds likely blew from the northeast resulting in elongate dunes with an asymmetric downwind point. The transverse crests of the smaller ripples/mega-ripple bed-forms surrounding the dune, echo the dominant downwind direction towards the southwest. [More at link]