Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4aa87d8283df07f4d10c15faeab2b0aa153d0c10f354abdd5d7089a50a272383' 
  AND token = 'ARniSmiWvPTgu6SLAmQqZhMNDAAbfVtat7XtfNz/TG8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}