SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '16ba42d9154d4fc961843867eba2684d13d4adab09557599172884fbccfbf8a9' 
  AND token = 'aWK8lIH3MkdaAfXEUqLv3S77GoinLgfXPKJfDYhmFzM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00055

JSON explain

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