SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '018c70fdbdd68610ab2d28ea268db545ada48469764cc1ed5291e4b885671577' 
  AND token = 'BF3iyW0btxfJMrfTvQ3gts7S7B1wVGAuTG/Jt8ACGpU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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