SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'eb532dc2d955060c3d1d68056aabb1d5f3347334933c43ee7dbd7f72d231da25' 
  AND token = '8/EZ/WGbvlg1ZVDwyWDVTQDiDs1JqL5rqBO0LEdjPTo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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