SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '86190e22ca81bda95874e6affa8fc75842742cf36eca445f380ce73adb83b4f7' 
  AND token = 'zO17sc7Q/B0Pu/eIQs2/xPLIHF+plQkKh3LBPs/o85A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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