The genera Dendrolycopodium and Spinulum are new to me. They are described in Haines' book "The Families Huperziaceae and Lycopodiaceae in New England". At this point they seem to be suggested rather than accepted names but I might see if I can get this book on loan to review it.

Hi lycopus,
I emailed Mr. Haines in regards to the taxonomy but no reply so far. But I did look on the net and have found the site of http://www.plantsystematics.org/ (linked below) and it, as of 2005, have developed a default taxonomy called YYPG (look in left side frame for link).
I checked with Kew but they are using the old Bentham and Hooker classification system Kew page

Kew Lycopodiaceae

Here is a link that might be useful: Plant Systematics Organization

I am interested in the reply that you get. Nomenclature changes happen so frequently now but it is often hard to find the reasoning behind them without a thorough search of the literature. My current institution is quite lacking with regard to access to recent publications. Would be nice to have access to a translation of this article:

Yatsentyuk S.P., Valiejo-Roman K.M, Samigullin T.H, Wilkström N., Troitsky A.V. 2001. Evolution of Lycopodiaceae Inferred from Spacer Sequencing of Chloroplast rRNA Genes. Russian Journal of Genetics, Volume 37, Number 9.

A phylogenetic tree of the family would really be interesting and I suspect the authors present one in this paper.