Subgenus Symplecthyma Rivalier, 1964

Symplecthyma Rivalier, 1964: 159

Type species. Prothyma nitida Rivalier, 1964: 160, nom. rep for lucidicollis: Horn, 1926 nec Chaudoir, 1869

Symplecthyma: Wiesner 1980: 124; Wiesner 1992: 58; Putchkov & Matalin 2003: 115; Dheurle 2012: 44; Cabras, Cabigas & Wiesner: 2016: 193; Wiesner 2020: 139; Wiesner & Anichtchenko, 2023.

The subgenus includes species characterized by small body size (8.5–11.5 mm), with labrum predominantly metallic in color, sometimes with margins slightly lighter.