SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '25adf0d81811f3a8494baf83df81c3e2798585a27c63a50fcc0d54858d1b64b3' 
  AND token = 'mGAO9qYxV15drbbwzOLQSdpd0C2DNOjv0s4RJGudwio=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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