SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6d8f9c633d150cfd81c9727fb7047b321a49422aa567ff497014e0eb1a20c37e' 
  AND token = 'hY0YmkQ6CZoyB4vEhIgOP6E1dj14xoK5zusq52cC9p0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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