SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '978ad8a24d4efc486f891c47c3b5d77bf312e0ef2e2e6c4649f8653c48b99578' 
  AND token = 'FwgpbGKt7rN0rYFYZCM9MbrFhmAjC/GQ21XVTiGwFrY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00011

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