Adult left valves of the ostracod Ilyocypris leptolinea Wang & Zhai, sp. nov. from the late Quaternary Xiaojinggou section of Inner Mongolia, China A–D XJG2-210-1 (holotype, 0.94 × 0.48 mm) A exterior view B interior view C interior view of the posterior part, showing the marginal ripplets D interior view of the anterior part, showing the marginal ripplets. Arrows and numerals indicate three inner lists on the calcified inner lamella E, F XJG2-206-4 E oblique-dorsal view F enlarged view of the rectangle in (E), showing the crossing pattern of the inner lists at the median part of ventral margin. Arrows and numerals indicate the three inner lists G XJG2-206-1, enlarged oblique-dorsal view of the median part of calcified inner lamella, showing the crossing pattern of inner lists H–J XJG2-199-2 (paratype) H interior view I interior view of the postero-ventral part, showing the marginal ripplets J Interior view of the antero-ventral part, showing the marginal ripplets. Arrows and numerals indicate the three inner lists. Scale bars: 200 μm (A, B, E, H); 100 μm (C, D, I, J); 50 μm (F, G).