SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd888e0489dc61f75411ab5a8d3ebd1570f0f63e61b3c3625cbaa4ab261e028dc' 
  AND token = 'XSAizICGs9UDFPR6KBKaXQFeKwi/mtv8ki4rn/wryJo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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