SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '909ee8822556b24d4f90ed62c3aebe8ae90ee3c1532526f05b3e38de5a974a54' 
  AND token = 'jrvQ/R5wAUJoQ30NjIH/tKgo+/Iw8e2ywrEFXPgGjIU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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