SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '70d8de2f9ef745c8bfef73c43c440402c64010c3e4ca88736b4141db91f5e49c' 
  AND token = 'uVqFb16PnA+/sZmQ1GuTuDl3hBPZwJriMWN2vKTqyMw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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