SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '49bd46a3fc0a990f6ca7e48efa6cd837e5bccf46c0da3860643aa28c9c9a1bae' 
  AND token = 'Tpb25uaT48mMsW+2EpggwZcVtUTr2nHkwTDlLA+SQPs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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