SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '401303ee064fccd9ffea24c0cac2d5a5bb64b36204243858c467bb02e5909a2b' 
  AND token = 'IUhIz6xg8fVtkSncxsryDUkduP1VYMsgh9WvCMAzyLk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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