SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'da432b7f51a8e8d7a3473c7730a573a307416e3ec7df99fe7d1bc24578e881f2' 
  AND token = 'jVb/QIfEYn/slUdzrzhCNuau/SUP7gTmYClLupWX22U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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