Fissidens buckii and F. quisqueyanus, spp. nov. (Bryopsida: Fissidentaceae), from Puerto Rico and the Dominican Republic

Abstract

Fissidens buckii from Puerto Rico and F. quisqueyanusfrom the Dominican Republic are described and illustrated. Fissidens buckii is compared with F. donnellii Aust. from which it is distinguished by its small size and unequal vaginant laminae. Fissidens quisqueyanus is compared with F. flavosetus Pursellfrom which it is distinguished by its monomorphic stems, unequal vaginant laminae, larger cells and weaker limbidia. In both F. buckii and F. quisqueyanus the smaller vaginant lamina of each pair narrows distally and ends on the costa. Recent collections ofbryophytes illustrate the fact that even relatively well studied neotropical areas can still yield species new to science. Based on a collection made by D. H. Norris (Humboldt State University, California) in the Dominican Republic and a collection made by W. R. Buck (The New York Botanical Garden) in Puerto Rico, the follow- ing new species of Fissidens are proposed. Fissidens buckii Pursell, sp. nov. (Fig. 6-11) Species haec a Fissidente donnellii statura minore la- minisque vaginantibus inaequalibus differt. Plants minute, 1.2-1.8 mm tall, erect, scattered. Leaves in 3-7 pairs, narrowly oblong to narrowly lanceolate, 0.8-1.5 mm long, perichaetial leaves longest, imbricate and often flabelliform in arrange- ment, acute to rounded, axillary hyaline nodules absent; margins dentate, coarsely so on vaginant laminae; costae strong, ending 2-4 cells below the leaf apices; dorsal laminae narrowing below, ending at the insertions or sometimes above, not decurrent; vaginant laminae 0.3-0.5 times the length of the leaves, unequal, the smaller of each pair narrowing above and ending on the costa; laminal cells in- crassate, irregularly quadrate to irregularly hexag- onal, 8.5-12 /tm long, coarsely mamillose-papillose. Probably rhizoautoicous; perigonia not seen; peri- chaetia terminal. Setae one per perichaetium, 2-3 mm long, yellow-orange; thecae erect and symmet- ric, 0.3-0.5 mm long; opercula rostrate from a conic base, ca. 0.4 mm long; peristome teeth strongly in- flexed when wet, divided 2/3 their length, finely papillose below, spirally thickened above. Spores (9-)11-13(-14) pm in diameter, smooth. Calyptrae not seen.