SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '289d147a720efcb758b578e3c42e255682c39db5278f3263a5a170f2410031bb' 
  AND token = 'bzDnFbKy4t9tg679UwESUGukJxQS6HbEcfQVDaitAsw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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