SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6baa20d1b67457048d6aaf58e011085515a562c7aa3b2be49ad72b9a2991571f' 
  AND token = 'X6JmG3xfTfTQjDkgEw0iSuhHvCFBblBJDHpYBmUSAxU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}