SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aea2a4f37031c0bfa6d44e9da751163b579a38df21976628802cdb0c4c7bccc1' 
  AND token = 'ktaIvxmh2334qApIyRARNQCuutvTpEaZ31p/F/DBgZM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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