SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0d9df8e2733dfaeccf8169e2f8bc359b9e8cac2333b31912f21d6d2fa1e9b439' 
  AND token = 'hEs+o2pzWOWOE2oa114J6ZrCMn6bd5OQWM2WWJL6rmw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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