SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '055b04cfad60472389a91652aa959efcdc7187c720e5036776ca14bfc955f2a5' 
  AND token = 'hQRSlkXctHHtXnBzXY0xmJIL65nUIVyTRvlRjkOTxlE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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