SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c153912ec141e871ac7c9b47cfde8b927727c9c21e72a7a27928b65cdeb4dce0' 
  AND token = 'DxouAHno1Pob6CZKeDGpv/zCImM1vZQoxlzDlo1C3Yw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

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