SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '43ffc195ca24dea47b0d7ffdad762fabb53ada0090954140ae34a4229bd56346' 
  AND token = 'oiS1FHdvFqR13axxM9MdRYacrmZKRVLiWCoIXcwdMQ0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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