SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c78bdea3acd24ee174688663dd7f4118a2d2fbb6d681b670ce4a0b74c63e4475' 
  AND token = 'ASXmCb0izPSHqPkfRGyKlRWfYvszR4S/UoDT/VgDTFo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

Explain
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Impossible WHERE noticed after reading const tables