SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'fd7329a7f42e2134a580ef29ab65faf4592621adfafb3d59f6098b3b8f2b5fa6' 
  AND token = 'l/xnwU5+KuYlWV77Mz1TdWeOHpE9ZDGGXz3r0I6xIDE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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