Template typed method in interface error.

I am trying to implement thread-safe queue adapter for std::queue

This is an interface:

template <typename T>
class ThreadSafeQueueIT {
public:
    virtual void push( const T& value ) = 0;
    virtual void push( T&& value ) = 0;



    virtual bool empty() = 0;
    virtual  T& front() = 0;
    virtual void pop() =0;

};

This is queue template implementation:

template <class T>
class ThreadSafeQueue : public ThreadSafeQueueIT<T>{

private:
    std::mutex mutex_;
    std::queue<T> queue_;

public:

    ThreadSafeQueue();

    void push(const T &value) override;

    void push(T &&value) override;



    bool empty() override;

    T &front() override;

    void pop() override;


};


template <typename T>
void ThreadSafeQueue<T>::push(const T &value) {
    std::lock_guard<std::mutex>(mutex);
    queue_.push(value);
}
template <typename T>
void ThreadSafeQueue<T>::push(T &&value) {
    std::lock_guard<std::mutex>(mutex);
    queue_.push(value);
}

template <typename T>
bool ThreadSafeQueue<T>::empty() {
    std::lock_guard<std::mutex>(mutex);
    return queue_.empty();
}
template <typename T>
T &ThreadSafeQueue<T>::front() {
    std::lock_guard<std::mutex>(mutex);
    return queue_.front();
}
template <typename T>
void ThreadSafeQueue<T>::pop() {
    std::lock_guard<std::mutex>(mutex);
    queue_.pop();
}

One of my interfaces has this virtual method:

virtual ThreadSafeQueue<std::shared_ptr<Json>> & getMessages() = 0;

And during compilation I get following error:

error: ‘ThreadSafeQueue’ does not name a type
     virtual ThreadSafeQueue<std::shared_ptr<Json>> & getMessages() = 0;

Why is this happening?