CONICET | Buscador de Institutos y Recursos Humanos

During the ongoing revision of the genus Philonotis Brid. in South America (Jimenez et al. 2014; Jimenez & Suárez, 2015), some herbarium samples collected in Chile and Perú and deposited in US, were identified as Philonotis osculatiana De Not., an acrocarpous mosses not previously registered to those countries (Menzel, 1992; Müller, 2009). The analysis of the type specimen confirmed their identity (Isotype: Colombia, ad fl. Napo, Osculati s.n, PC! PC0133484).Philonotis osculatiana is a species described by De Notaris in 1859 on the basis of samples collected in Napo region (Colombia) by Osculati. Later, Florschütz-de Waard & Florschütz (1979) and Churchill & Linares (1979) confirmed its presence, but it was never recorded to any other country until date.Philonotis osculatiana is a distinctive species characterized in the following description: Plants medium size, green to yellowish-green, growing in dense turfs. Stem red, densely tomentose below, 2.3-3.2 cm long. Leaves triangular-lanceolate; 1-1.2 x 0.2-0.4 mm, apex acuminate; margin bluntly serrulate in the upper 2/3 of the leaf, serrulate to dentate in the lower half, plane; costae robust and well defined, percurrent to rarely short-excurrente; costal transverse section rounded, stereid band rounded in form; upper laminal cells rectangular to sub-linear, 16-26 x 6-8 µm, basal cell oblong to oblong-rectangular, 25-30 x 14-15 µm, papillae at upper cell ends. Microphyllous branches presents. Dioicous. Perichaetia gemmiform. Setae erect, reddish-brown. Capsule inclined, globose to sub-globose, furrowed when dry, striated when wet; cryptopores at base, annulus absent. Operculum conic. Peristome double, reddish-brown; exostome teeth lanceolate, trabeculate. Spores reniform, reddish-brown, 29-32 µm diameter; densely baculate.It can be easily confused with Philonotis fontanella (Hampe) A. Jaeger by the habit of the plants, and the yellowish-green color, the costae strong and robust, percurrent to sometimes excurrent, and the distal position of the papillae on the laminal cells, but differs from it by the presence of triangular-lanceolate leaves, margin plane, dentate to weakly-serrate on the apex, laminal cells oblong-rectangular to sub-linear, papillose on the distal angles, and costal transverse section rounded with stereid band rounded in form. This last character has a great taxonomic value, since it is the only one species of the genus from South America that present it.In Chile P. osculatiana was collected at the metropolitan region, while in Peru was found about two thousand feet above the Urubamba River near Machu Picchu, elev. ca. 7000 feets.