SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e74cdbf2c482be11c8f141abaaddec1d17c2476b73cf568613595944943b70e8' 
  AND token = 'DOzbrgHsSlXoLOvUpHR+upy+Ozqj25f1NTD1RwjobZs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

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