SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5402895c37ca17262b7d690ca7fcfca6d30986391b5f5a505c81a6185013eb1f' 
  AND token = 'd/xJ61UwvbDWaUaiedXHgu562TPh5FWsfy3n0F076mc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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