Orthotrichum underwoodii, sp. nov. (Orthotrichaceae, Bryopsida) from California

Abstract

A new moss species, Orthotrichum underwoodii F. Lara, Garilleti & Mazimpaka, is described from material kept in the New York Botanical Garden Herbarium. The new taxon is included in subgenus Pulchella (Schimp.) Vitt, and characterized by leaf cells pluripapillose; capsule immersed, cylindric, abruptly contracted to the seta whose apical part is hidden in a hollow; operculum conic-convex; stomata cryptopore and located in the lower capsule half: capsule with 8 short exothecial bands, comprising 2(3) cell rows; exostome with 16 whitish teeth recurring irregularly; and endostome with 16 segments uniseriate. Orthotrichum underwoodii is taxonomically close to O. handiense F. Lara, Garilleti & Mazimpaka recently described from the Canary Islands (Spain). Differences of the two mosses and possible confusion of the new species with others are discussed.