Miscellaneous Notes on the Genus Sphagnum. 3. New Species from Brazil

Abstract

Seven Brazilian species of Sphagnum are described and illustrated as new: S. buckianum in sect. Sphagnum; S. exquisitum, S. acutirameum, S. geraisense, S. divisum, S. homophyllum, and S. obliquefibrosum in sect. Subsecunda. The presence of S. irwinii in the state of Minas Gerais is recorded, together with illustrations and notes on variation. The Sphagnum flora of Brazil has presented a surprising diversity, and a number of new species have turned up in collections kindly sent to me for identification by William R. Buck of the New York Botanical Garden and Dale H. Vitt of the University of Alberta, most of them collected by Dr. Buck and Daniel M. Vital of the Instituto de Botinica, Sio Paulo. SPHAGNUM (sect. SPHAGNUM) IRWINII Crum, J. Hattori Bot. Lab. 63: 77. 1987. (FIG. 1-6) BRAZIL. MINAS GERAIS. Near Pico da Carapu a, Serra do Caraqa, mun. de Santa Barbara, 20007'S, 4331 'W, on open, rocky slopes, Vital 7695, 18 November 1977 (ALTA, MICH, SP). This collection, not in the best condition, differs in no important way from the type, from the state of Goiais, except for being tawny below and pinkishbrown above rather than yellowish throughout, and having leaves somewhat spreading but not noticeably curved-secund or 5-ranked. The species is especially interesting because the green cells of branch leaves, as seen in section, are triangular and exposed only on the inner surface, and the hyaline cells are plane on the inner surface but bulging on the outer, with densely papillose side walls. Sphagnum brevirameum Hampe differs especially in having green cells central and included. Sphagnum itacolumitis C. Miill. & Warnst. ex Warnst. has triangular green cells, but the stem and branch leaves are essentially similar. Sphagnum brasiliense Warnst. has fusiform to narrowly truncate-elliptic green cells and dimorphous stem and branch leaves. The accompanying illustrations were made from the Minas Gerais material. Unfortunately the papillosity of branch leaf hyalocysts of the type of S. irwinii was incorrectly shown. The papillae are on the inner surface of side walls of hyaline cells, as illustrated here (FIG. 4), not on the inner surfaces of green cells. SPHAGNUM (sect. SPHAGNUM) BUCKIANUM sp. nov. (FIG. 7-15) Plantae admodum parvae, laete-virides. Hyalodermis caulina stratis 2-3, aporosa vel rare uniporosa, efibrillosa. Folia caulina 1.5-1.7 mm longa, rotundo-ovata vel lingulata, marginibus lateralibus sulco resorptio; cellulae hyalinae superne fibrillosae, non septatae, exteriore folii poris perpusillis, paucis, saepe in angulis conjunctis sitis, interiore poris 2-3 admodum magnis in angulis dispositis instructae. Fasciculi ramorum ramis duobus; hyalodermis ramorum efibrillosa, apice cellularum rare porosa. Folia ramulina 1.5 mm longa, ovata, concava; cellulae hyalinae dorso foliorum poris magnis in angulis conjunctis sitis, interiore poris aut pseudoporis 2-3 ad angulas et commissuras dispositis instructae; cellulae chlorophylliferae sectione transversali ellipticae inter hyalinas mediae et utroque latere foliorum inclusae; cellulae hyalinae, ubi parietibus inter se continguent, per spatium coalitae, intus in pariete laeves. Plants bright green, rather small. Stem cortex in 2-3 layers, without fibrils, aporose or rarely uniporose. Stem leaves 1.5-1.7 mm long, rounded-ovate to lingulate, bordered all around by a resorption furrow, rounded and ? cucullate at apex; hyaline cells fibrillose in upper 1/2-3/4, undivided, on outer surface with 3-4 very small rounded corner pores, often in 2's or 3's at adjacent comers, efibrillose cells toward base with 1-2 (-3) larger rounded median pores, on inner surface with 2-3 moderately large elliptic pseudopores in comers. Branches in fascicles of 2 (both spreading); branch cortex efibrillose, with some cells apically porose. Branch leaves 1.5 mm long, ovate, deeply concave, on outer surface with large elliptic ringed pores grouped in 3's at adjacent corners, on inner surface with 2-3 pores or pseudopores of varied sizes at angles and commissures; green cells central, included, hyaline cells with smooth walls, somewhat convex on both surfaces. BRAZIL. SAo PAULO. MUN. GUAPIARA: Serra Paranapiacaba, Fazenda Intervales, summit of Morro de Mirante, 1000-1100 m elev., ca. 24016'S, 48025'W, dry in exposed 0007-2745/92/419-429$1.25/0 This content downloaded from 157.55.39.102 on Thu, 23 Jun 2016 06:38:26 UTC All use subject to http://about.jstor.org/terms 420 THE BRYOLOGIST [VOL. 95