SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1537aa4d34e00cdce1813436176bfcaa5ff463083026b031002b4c49b71d2575' 
  AND token = 'y1eZgjRc8Rg3bEiTQ8WZQg8rIjkrXe2/ONSQz4dwg7M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

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