SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0693feb1df9f8f961ef2f83983f5336ad9c67152da64e8321811fabc83dd19b5' 
  AND token = 'NqAv53+jPPRKb9OZkQWgfEj1PNHKz+1GSyGEosl0i1Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}