SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3259f8259334548319542cf3edf6b5bbd1511d81a2324dec64d001a2632c43dc' 
  AND token = 'Iw/Vwmg6OxDj/TqXj3RbtmkalPtirG79eyPWWAhBmSU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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