SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7cc5d251fa13639edf55930dc83515175faeb1c1c5cd77bdbc400eddd863d4b4' 
  AND token = 'A3jOqo7cwrPQ215n5PDEDp+NlNwK1PtNAssoqtFJ2Zo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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