SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8bd28a8bea33fc051a024a1655b90a3b01cd674952d47d0eb287869e79cffa49' 
  AND token = 'KTsOkOEIEIsPmV0N7uqeaBxe+ILmgvko+LOQvjt8V8E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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