Wrapping additional parameters to variadic parameter pack in c++11

Based on my previous question here, I am writing a small class to help me distribute work to a bunch of threads. While constructing the thread I would like to pass a loop counter as an additional parameter to the parameter pack to be used as a thread_id. Is this possible?

qthread.h:

#ifndef QTHREAD_H
#define QTHREAD_H

#include <vector>
#include <thread>
#include <memory>

class qthread
{
    std::vector <std::shared_ptr <std::thread>> threads;
public:
    // Constructor
    template <class Fn, class... Args>
    qthread(Fn&& fn, Args&&... args)
    {
        size_t maxNumThreads = std::thread::hardware_concurrency() - 1;
        for(size_t i = 0; i < maxNumThreads; i++)
        {
            // While constructing the thread I would like to also pass i as a thread_id to the function in the parameter packing
            threads.push_back(std::make_shared <std::thread>(std::forward<Fn>(fn), std::forward<Args>(args)...));
        }
    }
    // Destructor
    ~qthread()
    {
        for(auto thr_p:threads)
        {
            thr_p->join();
        }
    }
};

#endif /* QTHREAD_H */

main.cpp:

#include <iostream>

#include "qthread.h"

void test(const size_t thread_id, int x)
{
    for(size_t i=0; i < 1000; i++)
    {
        x += i;
    }
    std::cout << "thread: " << thread_id << ", total: " << x << "\n";
}

int main()
{
    qthread(test, 5); // Distribute the 'test' task to n threads -- note that this doesn't work in this case since the function requires two parameters
}