SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4050d254fd5ae1ad74821c24e49fdab63b5698080783e8898855e855763fbc96' 
  AND token = 'Ht0Pza4Dwc4cGp7fjQTAfmqMBw0UkvrcsU3WKlC90tc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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