SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2ebe2be0d0c5aa4ddfec9adf3cb31bb5c17a5625f3fb7ec7dda71a30f632d234' 
  AND token = 'zQhv3DLRsuHsNOHki0phXVN7Odp8WrPOJoy0mRTT9fo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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