SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '356599b54b7541a11d4c9b6d8e4b5df1a76f5f406bec6a570e74a398763df253' 
  AND token = 'NApIj24zVOehe2q+Xv+7pxJhVMtbsGW1sIMID3DkQQU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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