SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5078325d6aa0c3190d47380fc78ee61ef68e740c54fe6bd6e5b1211e6e14e3ba' 
  AND token = '1KtSbERA3Jr5EB/WEGx7iISVhC3PO1qEd0YXzo6da/E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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