SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f2754360dabd51e51ed6bd0fa1b904a5271b7bb69248d42f528aa9ab5aeda861' 
  AND token = 'Yta6bFbpb/zi7jmUTDjd81qE1RxBFgQwhy8A60Fno7U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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