Chaco castanea. AMale holotype habitus, dorsal viewB Male holotype maxillae and labium showing cuspules C Female paratype habitus, dorsal view DFemale paratype maxillae and labium showing cuspules.
Chaco costai. A Male habitus, dorsal view B Male maxillae and labium showing cuspules C Female habitus, dorsal view D Female maxillae and labium showing cuspules E Chaco costaifemale ambushing in the burrow entrance, see the flap-like door FHabitat of Chaco costai showing psammophyte vegetation.