SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dde8ed3b0d27468570e7d838a5de2ededecdc9da5d7ee9bb3c6386f4a2264e0f' 
  AND token = 'jvi7mmQpPYEA0G1YIHKcvstxMPh/6GPp3QpkyoKBBsA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

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