SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b9ffcac9834e6325a0f554c10b1e064330e00a05fd47673f91898bbce27eae32' 
  AND token = 'qLKddrZdw9p5VPbAs2i/WXC7Goa5Mvy9KOpE3ZMwH1Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00008

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