Colleagues in California described a new species of moss, and several types (i.e., specimen upon which the original description is based) are deposited in the CONN herbarium, further enhancing its significance as a biodiversity repository.
Toren, D. R., K. M. Kellman, and J. R. Shevock. Archidium crassicostatum (Archidiaceae), a new and long-overlooked species from California, USA. Madroño 63: 348–352. pdf
Abstract: Archidium crassicostatum D.R. Toren, Kellman & Shevock is described and illustrated, and is currently known from two counties from California. It appears to be the sole species of the genus from the state and is well marked by its exceptionally wide costa, which can occupy as much as one third the width of the leaf base. Previous reports of Archidium alternifolium (Dicks. ex Hedw.) Schimp. and A. donnellii Austin from California are actually A. crassicostatum. Details of habitat, ecology, and distribution are given and morphological distinctions among similar-looking but unrelated taxa are discussed.