SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a3aa54a9aaef010a60698e29a4210db4753032fb2d2b03b8e28e344d9bedcd1b' 
  AND token = 'qzgRizqZ+lGx1Rx2DOsqfUcZqxg4ceh9KXy3elEteDM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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