SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '72b7c3c5f560ce60632232de21c65a60f76a76deaa4ea5bda798541fe4f130a5' 
  AND token = 'rHQMVhpl3BkwdZD/jgiTjCgYtNdDW4azxHEPnKGXkZk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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