SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a7ee0b3da7f6218b52d3f73f732b1e17bff8fe1cf190950ec5ab0839ec353584' 
  AND token = 'oIV9BEvPocJY/+wURSJHfTY3YUJ04KGfuyk50WqyuwY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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