Caldasia 23(1): 203-212 DIVERSITY AND HABITAT DIFFERENTIATION OF MOSSES AND LIVERWORTS IN THE OF , S. ROBGRADSTEIN Institute of Plant Sciences, University of Gottingen, Untere Karspiile 2, 37085 Gottingen, Germany

DANAGRIFFIN I11 Florida State Museum, University of Florida, Gainesville, Florida 3261 1, U.S.A.

MARIAISABEL MORALES Escuela de Biologia, Universidad de Costa Rica, Sun Josk, Costa Rica

NALINIM. NADKARNI The Evergreen State College, Olympia, WA 98505, U.S.A. ABSTRACT An inventory of the understory and canopy of 4 ha of lower montane cloud forest at Monteverde, Costa Rica, yielded 190 bryophyte species: 133 hepatics, 56 mosses and 1 hornwort. Thick branches of the lower canopy were by far the richest habitat in terms of number of species (99), trunks from 1 m upwards had 65 species, lianas, shrubs, saplings, or living leaves in the understory had about 36-46 species each, and 16 species were found on rotten logs. The figures are illustrative of the great diversification of microhabitats of bryophytes in a tropical montane cloud forest. About 36% of the species, including more than half of the corticolous ones, occurred exclusively in the canopy. It appeared that the percentage ofbryophyte species restricted to the canopy may be the same in lowland and montane rain forests, in spite of the great differences in species abundance and composition in the two kinds of forest. Key words. Bryophytes, Cloud forest, Biodiversity, Costa Rica. RESUMEN Ciento noventa especies de briofitas (133 hepaticas, 56 musgos, 1 antocerote) fueron encontradas en un inventario hecho en 4 hectareas del sotobosque y el dosel en el bosque nublado (1 500 m) de Monteverde, Costa Rica. Las ramas gruesas del dosel fueron la porcion mhs rica en termino de numero de especies (99), en troncos habia 65 especies, lianas, arbustos, hrboles juveniles o hojas vivas en el sotobosque tenian entre 36-46 especies cada una, y 16 especies fueron encontradas en troncos en des- composition. Las cifras ilustran la gran diversidad de microhabitats de briofitas en el bosque nublado. Cerca de 36% de las especies, incluyendo mas de la mitad de 10s corticolos, se presentaron exclusivamente en el dosel. Parece que el porcentaje de especies de briofitas restringidas al dosel podria ser el mismo en bosques de tierras bajas yen bosques nublados, apesar de la gran diferencia en abundancia y composi- cion taxonomica de las briofitas en las dos clases de bosque. Palabras clave. Briofitas, Bosque nublado, Biodiversidad, Costa Rica. Diversity and habitat differentiation of mosses INTRODUCTION of epiphytic bryophytes in rain forests is high and minimum areas for sampling therefore Tropical rain forests, including montane cloud relatively small. Complete sampling of4-5 trees forests, harbour a large diversity ofbryophytes, (from base to outer canopy) may yield over probably due to the great variety of 75% of the flora of a homogeneous forest microhabitats in these forests. Of an estimated stand (Cornelissen & ter Steege, 1989; Wolf, 4000 species (2650 mosses, 1350 hepatics) 1993; Gradstein et al., 1996). Costa Rica's occurring in tropical America, about 80% of Monteverde Cloud Forest Reserve is one the the hepatics and 50 % of the mosses are best studied montane moist forests world- confined to these forests (Gradstein et al., in wide. Monteverde: Ecology and press). Most of the bryophytes in tropical rain Conservation of a Tropical Cloud Forest forest are epiphytes and their abundance varies (TVadkami & Wheelwright, 1999) incorporates considerably with elevation. In lowland rain contributions of 140 authors and over 1800 forests, below 500 m, bryophyte cover is poor references. Vascular epipyhtes have been and mostly restricted to the canopy. In montane studied in detail by Nadkarni and associates rain forests, especially in the very moist cloud (e.g., Nadkarni, 1986; Nadkarni & Matelson, forests, growth of epiphytic bryophytes is 1992;ingram & Nadkami, 1993). In contrast, usually much more luxuriant. Moreover, the very little work has been done on the forest floor may be covered with dense bryophytes of Monteverde. Reed & Robinson bryophyte carpets. The lower temperatures and (1971) published a first list of 164 species (90 higher light levels in the cloud forest and the mosses, 73 hepatics, 1 hornwort) based on availability of plentihl water due to impact of fog random collecting in the forests and in pasture favour the accumulation of dead organic mate- areas. Additional species were reported by rial on the ground and the abundant growth of Gradstein et al. (1994) and Sillet et al. (1 995). the epiphytic and terrestrial bryophytes The latter authors analysed the epiphytic (Richards, 1984; Gradstein & Pocs, 1989). bryophyte flora in the canopy of six Ficus Our understanding of bryophyte diversity of tuerckheimii trees, three in the dense primary tropical rain forests is still fragmentary. Com- forest and three isolated ones in adjacent plete inventories are very scarce. Most studies pasture land, and could demonstrate that the only deal with part of the flora, leaving two sets of trees had very different species "difficult" groups such as the tiny Lejeunea- assemblages. ceae (Hepaticae) unidentified. Moreover, This paper deals with the bryophyte diversity attention is usually restricted to the lower part in the cloud forest of Monteverde. The main of the forest, whilst the higher portions of the purpose of this study was to described the trunks and the canopy branches are neglected composition and habitat differentiation of the due to their inaccessibility (Wolf, 1993). flora and to determine floristic differences Cornelissen and Gradstein (1990) found that between the canopy and understory of the in lowland rain forest of Guyana about 50 % forest. of the bryophyte species occurred only in the tree crowns and on the upper portions of the MATERIAL AND METHODS trunks, over 10 m above ground level. In contrast, only 14 % of the species were We conducted an inventory of bryophytes exclusive to the understory. The number of within a 4 ha study site, consisting of four species restricted to the canopy in cloud plots of one hectare each, in Monteverde forests is still unknown. Another important Cloud Forest Reserve during November 1992 finding of recent work is that species density and January 1994. The Monteverde Cloud S. Rob Gradstein et a[. Forest Reserve is situated in northcentral ofthe canopy. The most frequent bryophytes Costa Rica (10°1 S'N, 84'48'W) along the crest on trunks, shrubs, lianas etc. in the understory of the continental divide in the Cordillera de were Plagiochila spp., Porotrichum Tilaran. The forest is subject to cloud-bearing korthalsianum and Radula antillana. Other trade winds that move across the Cordillera common taxa included Metzgeria leptoneura, from the northeast. The trade winds occur Lepidopilum muelleri, Omphalanthus throughout the year, but most frequently filiformis, Taxilejeunea pterigonia and deliver mist between November and May. Trichocolea tomentosa. In well-lit sites the Total annual annual rainfall is 2000-2500 mm, pendent mosses Phyllogonium fulgens and most of which falls during May to October, various Meteroriaceae were frequently seen but fog and mist may contribute an additional together with the robust hepatics Porella 500-2000 mm of annual precipitation (Ingram swartziana, Bryopteris filicina, Radula & Nadkami, 1993). gottscheana and Plagiochila spp. The 4 ha study site is in the lower montane On trunk bases Cephalozia crassifolia, rain forest (1550 m elevation) about 1 km Fissidens spp., Hookeriopsis falcata, southwest of the headquarters of the reserve, Hypopterygium tamariscimum, Lophocolea on the leeward, Pacific side ofthe Cordillera. connata, Telaranea nematodes and various The primary forest is 20-30 m high with a few unidentified species of Lejeunea were quite emergents to 35 m tall. Ocotea tonduzii common. Other taxa characteristic of this (Lauraceae), Ficus tuerckheimii (Moraceae) habitat included Calypogeia spp., Pallavicinia and Meliosma ideapoda (Sabiaceae) are the lyellii, Cyrtohypnum schistocalyx (= Thuidium principal canopy tree species, making up ca. schistocalyx), Leskeodon andicola, 40% of total basal area of trees. Octoblepharum erectifolium and Syrrhopodon About 350 collections of bryophytes were spp. Species of Bazzania occurred here and gathered randomly in the four hectare plots. there on trunk bases but were much more An average of 2-3 trees per plot were climbed common in the forest canopy. and samples were taken from branches of the The forest floor had much rotten lower canopy. Sampling of the outer canopy wood (logs, fallen branches) and this was also was done from recently fallen trees. In general, an important habitat for bryophytes, e.g., the canopy sampling was less detailed than the thalloid hepatics Monoclea gottschei and inventory of the understory, however. The Riccardia spp. and the mosses Hookeriopsis collectionswere deposited in FLAS, U and USJ. falcata, Mittenothamnium reptans, Plagiomnium rhynchophorum and RESULTS AND DISCUSSION Pyrrhobryum spiniforme. The single homwort encountered in the study site, Megaceros 1. Distribution of species in tlte cloudforest. vincentianus, was also a species of rotten Bryophytes were abundant on treelets, shrubs, logs. The majority of the species of rotten lianas and rather exposed trunks in the forest logs also occurred on the trunk bases, understory and, particularly, on thick branches especially on rotten, humose ones. of the inner forest canopy. On trunks in deep Canopy. The lower, * horizontal branches shade, bryophyte cover was usually rather of the canopy were thickly covered by scanty. Hepatics were more abundant than bryophyte mats. Species of Bazzania, mosses, both in terms of biomass and in Lepidozia, Macromitrium, Plagiochila, number of species. Herbertus and Frullania convoluta were the Understory. The bryophyte flora ofthe most prominent elements. Macromitrium and forest understory was very different from that Herbertus were restricted to the canopy but Diversity and habitat differentiation of mosses species of Bazzania and Lepidozia also The most common ones included Odonto- occurred lower down in the understory. Plants lejeunea lunulata and species of of Frullania convoluta fallen from the Cyclolejeunea (C. convexistipa, C. peruviana), canopy sometimes continued growth on Drepano-lejeunea and Aphanolejeunea. branches in the understory. Other bryophytes characteristic of thick 2.Species riclzness. Our inventory yielded 190 canopy branches and lacking in the bryophyte species (Table 1): 133 hepatics, 56 understory included the hepatic genera mosses, and 1 hornwort (Megaceros Frullania, Adelanthus and Ceratolejeunea vincentianus). The average number per (the latter sometimes forming extensive dark hectare was 88 species, with highest number mats), furthermore Kurzia capillaris, in plot 2 (1 18) and lowest number in plot 4 Leptoscyphus porphyrius, Syzygiella (74). In comparison, a very detailed analysis pectinformis, Tylimanthus laxus, and the ofthe canopy by Sillet et a1 (1995) found 109 mosses Acroporium pungens, Bryum bryophyte species on three Ficus capillare, Campylopus arctocarpus, tuerckheimii trees in the Monteverde cloud Leucobryum giganteum, Leucoloma forest. This suggests that our canopy species cruegerianum, Pilotrichella flexilis, list is still incomplete. Squamidium nigricans, and Syrrhopodon Species-area curves showed that one plot lycopodiodes. Light-green mats of Papillaria yielded 45 % of total diversity, and two plots imponderosa and the pendent Phyllogoniums yielded 75% (Fig. 1). In comparison, when and OmphalanthusJiliformis were common bryophyte diversity on trees only is studied both in the canopy and in the understory, (excluding shrubs, logs etc.), the 75% level is behaving as ecological "generalists". usually obtained by analysis ofjust four trees Fine twigs of the outer canopy harboured (Wolf, 1993). a rich ramicolous bryophyte community The absolute dominance of hepatics over characterized by Daltonia gracilis and many mosses at the study site in terms of species small species of Lejeuneaceae. Some of these number is characteristic of these neotropical also grew on living leaves. Foliicolous moist forests. In palaeotropical forest, mosses bryophytes, most of them Lejeuneaceae, were tend to be more abundant (Gradstein & Pocs, abundant especially in the forest understory. 1989). Plagiochila was by far the most

t 2 3 Plot Number Fig. 1. Species-plot relationships. S. Rob Gradstein et al. speciose genus (18 spp.), followed by the figures are illustrative of the great hepatic genera Lejeunea and Bazzania (7 spp. diversification of microhabitats of bryophytes each), and Frullania and Radula (6 spp.). in a tropical montane forest. Among the mosses, Lepidopilum and Species richness in the canopy compared Macromitrium (4 spp.) were the most speciose to the understory was 117 vs. 121. Of these, genera, the former mainly in the understory, 48 (25%) occurred both in the canopy and the the latter very abundant in the canopy. understory, 38% were exclusive to the understory, and 36% to the canopy (Fig. 3A). 3. Habitat diversification.The distribution of the species of the species over the various microhabitats is shown in Fig. 2. Thick branches of the lower canopy were by far the I5O- richest habitat for bryophytes and yielded --, about 100 species. Trunks (from 1 m upwards) I...... loo- ...... had 65 species, living leaves 46 species and : : :m~: : ...... trunk bases 36 species. Fourty species were ...... : Understow zS ...... , : : : :: : :: found on lianas, poles and small branches on 50- ':...... "...... '...... 28% . .. I .. - ./, ..: .. I ,a. . ,I' shrubs, sapling etc. in the forest understory. .:. :;,,:;+ '...%, '...%, . . , Understory @k. The lowest number of species (17) was found o . .". .. ".'...... , on rotten logs; however, half of these were A B exclusive to rotten logs and not found Fig. 3. Comparison of bryophyte species elsewhere. A similar percentage was obtained richness in understory and canopy. A. Total for epiphylls: about half of the foliicolous species diversity. B. Corticolous species species (23) were only found on living leaves, diversity (species ofrotten logs and epiphylls others occurred also on other substrates. The excluded).

Br Fo Lo Sh Tr Trb Tw Fig. 2. Distribution ofbryophyte species over different microhabitats. For abbreviations see Table 1. Diversity and habitat differentiation of mosses Table 1. Bryophyte species collected in the 4 ha study site (hectare plots 1-4) in the Monteverde Cloud Forest Reserve.

PLOT CANOPY UNDERSTORY PLOT CANOPY UNDERSTORY

HEPATICAE Aphanolejeunea exigua 2.4 Fo Acrobolbaceae Evans Tyl~~nanthr~slaxus Spruce 1, 2. 4 Br A gracil~sJov.-Ast 1,2. 3. Fo Adela~~thaceae 4 Adelanthus carabayensis 1 Br A subdiaphana var. 1. 2. 3. Fo (Mont ) Grolle cristulata (Schust ) Pocs 4 A decip~ens(Hook.) Mitt 2 Br Brachiolejeunea laxifolia 2 Tw A p~tt~eri(Steph.) Grolle 4 Br (Tayl.) Schiffn Aneoraceae Bryopteris filicina (Sw.) 1. 2. 4 Br Sh, Tr Riccardia fucoidea (Sw) 4 Br Lo Nees Schiffn. Ceratolejeunea cornuta 2 Br R SP 1, 2, 3, Br Lo (Lindenb.) Steph. 4 C. maritima (Spruce) Steph 1, 2. 4 Br Fo Calypogeiaceae C. sp 1.2 Br Calypogeia crenulata I Trb Cheilolejeunea rigidula 1, 2 Br Bischler (Mont ) Schust C peruviana (Nees & 3 Trb Cololejeunea cf standleyi I. 2,3, Fo Mont ) Steph Herr 4 C rhombifolia (Spruce) 3 Trb Colura ulei Jov -Ast 2 Tw Steph Cyclolejeunea accedens 2. 3, 4 - Fo C rhynchophylla (Herz) 2 - Trb (Gott.) Evans Bischler C convexistipa (Lehm & 1.2.3, Fo Fo Cephaloziaceae Lindenb.) Evans 4 Cephalozia crassifolia 1, 2, 3. Br Lo, Sh, Trb C luteola (Spruce) Grolle 4 Fo (Lindenb. & Gott ) Fulf 4 C peruviana (Lehm & 1, 2,3, Fo, Tw Fo Odontoschisma longiflorum 4 Br Lindenb )Evans 4 (Tayl ) Steph. Dicranolejeunea axillaris 2 Tw Geocnlycaceae (Nees & Mont.) Schiffn Leptoscyphus porphyrius 2 Br Diplas~olejeunea alata lov - 2 Tw (Nees) Grolle Ast Lophocolea connata (Sw.) 1, 2. 3, - Lo, Trb D brunnea Steph 3 Fo Nees 4 D cavifolia Steph 2.3 Tw Fo L. muricata (Lehm ) Nees 2. 3,4 - Fo. Sh. Tr, Trb D johnsonii Evans 1.4 Br Fo L, trapezoidea Mont 2 Br D montecristensis Winkler 3 Fo Herberlaceae Herbertus divergens Steph. I Br D pellucida (Meissn, ex 1. 2, 3, Tw Fo Spreng ) Schiffn. 4 H, junipero~deus (Sw.) ? Br Drepanolejeunea 1 Fo Grolle campanulata (Spruce) Stepli H pensilis Tayl. 1, 2.4 Br Jubulaceae D. inchoata (Meissn.) Evans 1,2, 3 Br, Tw Fo Frullania arecae (Spreng) 2 Br Gott D lichenicola (Spruce) 2 Tw F brasiliensis Raddi 2.4 Br Steph. F, convoluta Lindenb. & 1, 2. 3, Br Sh (fallen from Ecll~nocoleadilatata (Evans) 3. 4 Fo Ha~npe 4 canopy?) Schust F exilis Tayl 1.2.4 Br, Tw Harpalejeunea aspera Grolle 3 Fo F laxiflora Spruce 2 Br F rtojanetrensis (Raddi) 2 Br H oxyphylla (Nees & 4 Fo Aongstr Mont ) Steph Jubula bogotensis Gott 3 Tr Lejeunea cephalandra 2 Br Jullgermanniaceae Spruce Syryg~ella pectiniformis 2 Br L. controversa Gott. 1.2.4 Lo. Sh. Tr, Trb Spruce (det. Vana) L aff filipes Spruce 1.2 Tw Lejeoneaceae L. flava (Sw ) Nees 1.2 Br Tr Anoplolejeunea conferta 7 Br L pl~yllobolaNees& Mont 2 Tw (Meissn ) Schiffn

Conventions Sh = lianas, poles and small branches (of shrubs, treelet: Br = thick, % horizontal branches of the inner forest and saplings) in the forest understory canopy Tr = tree tr~~nks(from 1 m upwards ) Fo = living leaves (foliicolous) Trb = bases of tree trunks (0-1 m) and roots ,o = rotten logs Tw = twigs of the outer forest canopy S. Rob Gradstein et al, Cont. Table 1

PLOT CANOPY UNDERSTORY PLOT CANOPY UNDERSTORY - L (subgen 2, 3 Sh, Trb Telaranea nematodes (Gott 1,2, 3. - Lo, Trb Otigoniolejeunea) sp ex Aust ) Howe 4 L. sp. A 2, 3 - Sh Metzgeriaceae L sp B 1.3 - Tr, Trb Metzgeria albinea Spruce 2 Br Lepidolejeunea involuta 1. 2 Br Fo, Tr Metzgeria decipiens (Mass ) 1. 2. 3. - Fo, Sh. Tr (Gott ) Grolle Schiffn. Leptolejeunea elliptica 2. 3 Fo M leptoneura Spruce 2. 3, 4 - Sh (Lehm & Lindenb ) Schiffn M liebmanniana Lindenb & 2 Tw Gott. L serratifolia Schlffn 1.2 Fo Monocleaceae Macrolejeunea lancifolia 1. 2. 3, - Fo. Sh Monoclea gottscliei Lindb 1, 2, 3, - Lo. Trb (Steph. ) Herz 4 4 Marches~niarobusta (Mitt) 4 Br Pallavicininceae Schiffn Pallav~cinialyellll Hook. 1, 2 Br Trb Microlejeunea acutifolia 3 Fo Symphyogyna brogniariii 4 - Lo Steph Mont M bullata (Tayl )Evans 1.2. 3 Tw Fo Plagiochilaceae M. stl-lcta (Gott et al ) 1, 4 Fo Plagiochila adiantoides Br Sh Steph 2, 3.4 Neurolejeunea brer~tel~l 2 Br (Sw.) Lindenb. (Gott ) Evans P aerea Tayl 1.2.4 Br P breutel~anaLindenb - Trb Odontolejeunea 2.3 Fo 1, 2, 3, decemdentata (Spruce) 4 Steph P crispabilis Lindenb 3 Sh 0 lunulata (Web ) Sch~ffn 1, 2, 3, Fo, Tw Fo P cristata (Sw ) Lindenb 1,4 Br 4 P d~versifoliaLindenb. & 2. 3 - Sh. Tr Omphalanthus filiform~s1, 2, 3, Br, Tw Fo, Sh Gott (Sw ) Nees 4 P gymnocalycina (Lehm & 2 Br Sh 0 grandistipulus Steph 2,4 Br Lindenb ) Mont. 0 ovalis (L~ndenb.& Gott.) 1, 2. 4 Br Fo, Sh P laxa Lehm & Lindenb 1, 2, 3 Br Sh. Tr, Trb Gradst P maniana Nees 2 - Sh Prionolejcunea schlimiana 1, 3 - Po, Sh P miqueliana Lehm & 2.4 Br (Gott ) Steph (det Grolle) Lindenb p SP 1.2 - Fo. Sh P raddiana Lindenb (= P 4 Br Tr Rectolejeunea berieroana 2, 3. 4 Tw Fo guillelniniana Nees & (Gott ) Evans Mont ) Stictolejeunea squamata 1,2 Fo P ~dischusteriRobins 4 - Sh (Willd ex Web ) Schiffn. P stolonifera Lindenb. & 2 Br Sylnbiezidium transversale 3 Br Gott (Sw.) Trevis, var. P stricta Lmdenb 1.2 Br Trb hookertanum (Gott et al ) P, subplana Lindenb 1.2 Br & Gradst van Beek P tenuis Lindenb. 2, 3, 4 Tw Tw, Sh (rare) Taxilejeunea sulphurea 3 Fo, Sh P sp. A 1.2 Br (Lelim, & Lindenb ) Schiffn P sp B 1.2 Br Porellncene T pterigonia (Lehm & Br Sh 2, 3, 4 Porella swartzlana (Web ) 1. 2, 3, Br Sh, Tr Ltndenb ) Schiffn Trevis. T, sp 4 - Lo Rndulncene Lepidazincene Radula antilleana Castle 1. 2. 3, Br, Tr Sh, Tr Bazzania affinis (Lindenb & 1. 2. 3. Br Tr, Trb 4 Gott ) Trevis 4 R frondescens Steph 1. 2, 3, Br. Tr Sh. Tr B breuteliana (Lindenb. & 2 Br Trb 4 Gott ) TIevis R gottscheana Tayl Tr Sh. Tr B denticulata (Lindenb. & 4 Br 1.2.4 R javanica Gott (= R 1 Tr Gott.) Trevis macrostachya Lindenb. & B gracil~s(Hampe & Gott ) 1.4 Br Trb Steph. Gott.) R stenocalyx Mont 3 - Fo B Ihookert (L~ndenb) 2.3.4 Br Trb (rare) Trevis R tenera Mltt. ex Steph 2 Br B longa (Nees) Trevis 1 Br, Tr Tr Scapaniaceae B stolonifera (Sw ) Trevis 7 Br Scapania ponoricensis Gott 4 Br (rare) Kurzia cap~llaris (Sw.) 1 Br Fo Glolle Trichocoleacene Lepidozla annata Steph 4 Br Trichocolea flaccida 3 Fo L cupressina (Sw ) Lindenb 1. 2 Br, Tr TRb (Spruce) Jack & Steph Trichocolea tomentosa (Sw ) 1, 2, 3, Br Sh, Tr L. squarrosa Steph 4 Br Gott. 4 Diversity and habitat differentiation of mosses Cont. Table 1

PLOT CANOPY UNDERSTORY PLOT CANOPY UNDERSTORY ANTHOCEROTAE Anthocerotaceae Leucohryaceae Leucobryum crispum C.M. 3 - Megaceros vincentianus 4 Lo Trb (Lehm. & Lindenb ) Steph. L. giganteum C M 1.2 Br Octoblepharum erectifolium 4 - Trb MUSCI Mitt Bal.tt.amiacene Meteoriaceae Leiomela bartramioldes 4 - Tr Meteorldium remotifolium 2. 3 Br Sh (Hook.) Par, (C M )Manuel Brachytheriacene ~piaia rmponderosaI 2, 3 I Br, Tw 1 Sll, Tr Rhynchostegium serrulatum 2 ~r (Tayl )Broth I (Hedw.) Jaeg Pilotrichella flexilis (Hedw) 2 Br, Tw Brynreae Aongstr Bryu~ncapillare Hedw. 2 Br P, pentasticha (Brid ) Wijk 3 Orthodontium pellucens I Br, Tr & Marg. (Hook ) B.S G. Squamidiu~n nigricans 2 Calymperaceae (Hook ) Broth Syrrhopodon incompletus I, 2, 3, Br (rare) Trb Mniaceae Schwaegr var berteroanus 4 Plagiomnium (Brid ) Reese 2, 3 Lo rhynchophorum (Hook.) T S lycopodioides (Brid ) 4 Br C.M. Kov Neckeraceae S. prolifer Schwaegr. var. 4 - Trb tenuifolius (Sull.) Reese Isodrepantum lentulum 1.4 Sh Dicranacene (W~ls) Britt Calnpylopus arctocarpus 1 Br Neckeropsis disticha I Trb (Hornsch.) Mitt (Hedw.) Reichardt Holo~n~triu~narboreum Mitt. I?IBr/ Porotrichum korthalsianum I, 2, 3 Sh. Tr, Trb (Dozy & Molk ) Mitt 4 Plongirostre (Hook.) Mitt 2, 3 Sh Porotrichuln mutabile ? L. serrulatum Brld. Hampe Fissidentaceae Orthotrichnceae Flssidens elegans Brid 3 Macromitrium cirrosum F 2 mitlotusThwaites I (Hedw ) Brid F. steerel Grout 1 M mam~llosumBartr. 7 Hookeriaceae s.1. M, cf parvirete Banr ? Callicostella pallida - 1, 2 M cf tonduzii Ren. & Card. (Hornsch ) Aongstr. 1, 2 Crossomitrlum patrisiae 2, 3 (Brid ) C M Phyllogoniaceae Phyllogonium fulgens Daltonia gracilis Mitt I Tw 2, 3, 4 Br Sh (incl, var. gracile) (Hedw ) Brid Hookerlops~sfalcata (Hook.) 1.2, 3, - Jaeg. 4 P vtscosum (P Beauv) 1. 2. 3 Br Sh Mitt. Hypnella cylnbifolia 1,2, 3, - (Hampe) laeg 4 Priollodolltaceae H. diversifolia (Mitt.) Jaeg 2 Br P. fusco-lutescens Hampe 2 Br Lepidopilum falcatulum 3 IP luteo-virens (Tayl )Mitt C M 1~1-ISh I L. muellerl (Hanlpe) M~tt 1, 2,3, - Rhizogoniaceae 4 Pyrrhobryum spiniforme 1, 2 Br Lo L scabriseturn (Schwaegr) 7 Br (Hedw ) Mitt Steere Rhizogonium lindigli 1, 4 Br (rare) Trb Leskeodon andicola (Mitt.) 1, 3 . (Hampe) Mitt. Broth Sematophyllaceae I,. ~!,hr.nsrs(Mitt.) ThCr. 3 Acroporiu~n pungens 7 Rhynchostegiopsis flexuosa Br 2 - (Hedw.) Broth (Snll.) C M Thuidiaceae Hypnaceae Cyrtohypnum schistocalyx Ectropothecium 2 Br 2. 3.2 Lo. Trb leptochaeton (Schwaegr ) (C M.) Buck & Crum Buck Thuidium antillarum Besch 7 Br Mittenothamnmm reptans 1, 4 Br I I I I I (Hedw ) Card Fo = living leaves (foliicolous) Hypopterygiaeeae Lo = rotten logs Hypopterygium 2, 3 - tamariscilnum (Hedw.) Brid Sh = lianas, poles and small branches (of shrubs, treelets and saplings) in the forest understory ~p Conventions Tr = tree trunks (from 1 m upwards ) Br = thick, horizontal branches of the inner forest Trb = bases of tree trunks (0-1 m) and roots canopy Tw = twigs of the outer forest canopy S. Rob Gradstein et al. In a lowland rain forest of Guyana, Cornelissen recorded anywhere else, was not found during and Gradstein (1 990) found that about 50% of this study. the bryophyte species were restricted to the canopy and 14% to the understory. The latter ACKNOWLEDGMENTS figures, however, were restricted to corticolous species and did not include species of rotten We are very grateful to Gregorio Dauphin for logs and living leaves. When calculations for inventorying epiphylls, Stephen Ingram for - the Monteverde study site are restricted to additional species records, Ricardo Solano for corticolous taxa, 52% of the species are logistical support, Riclef Grolle, Andrea exclusive to the canopy and 20% to the forest Lucking, Elena Reiner-Drehwald, Jiri Vana understory (Fig. 3B). It thus appears that the and K. Yamada for help with identification, and percentage of species restricted to the canopy Frans van Dunne and Ingo Holz for preparing may be the same in lowland and montane rain the figures. Fieldwork in Costa Rica by the forests, in spite of the great differences in first author was supported by the Netherlands species abundance and composition in the two Foundation for Tropical Research (WOTRO) kinds of forest (see also Gradstein, 1995). and the National Geographic Society (grant to Nalini Nadkami). 4. Floristics. At least 19 species appeared to be previously unreported from Costa Rica LITERATURE CITED (Gradstein et al., 1994): the hepatics Adelanthus carabayensis, Bazzania affinis, CORNELISSEN,J. H. C. & H. TER STEEGE1989. Calypogeia crenulata, C. rhombifolia, Colura Distribution and ecology of epiphytic ulei, Cyclolejeunea accedens, Frullania exilzs, bryophytes and lichens in dry evergreen F. laxzjlora, Kurzia capillaris, Lophocolea forest of Guyana. Journal of Tropical connata, Marchesinia robusta, Metzgeria Ecology 5: 29-35. albinea, M. decipiens, Plagiochila CORNELISSEN,J. H. C. & S. R. GRADSTEIN1990. rudischusteri, Prionolejeunea schlimiana, On the occurrence of bryophytes and Radula antillana, R. frondescens, R. tenera, macrolichens in different lowland rain forest and Syqgiella pectin iformis. Three of these, types at Mabura Hill, Guyana. Tropical Bazzania affinis, Lophocolea connata and Bryology 3: 29-35. Radula antillana, were surprisingly common DAUPHIN,G. 1999.Bryophytes of , in the forest. Among the mosses and hornworts, Costa Rica: diversity, biogeography and none were new to the country. ecology. Rev. Biol. Trop. 47: 309-328. The list includes several rare bryophyte GRADSTEIN,S. R. 1992. The vanishing tropical species, known otherwise from only very few rain forest as an environment for bryophytes localities. Plagiochila rudischusteri is known and lichens. In: J. W. Bates & A. W. Farmer from a few localities in northern Venezuela, (eds.), Bryophytes and lichens in a changing Panama and Pacific Colombia, Syzygiella environment, p. 234-258. Oxford Science pectiniformis is a rare northern Andean Publications, Oxford. species, and Calypogeia rhynchophylla is GRADSTEIN,S. R. 1995. Diversity of Hepaticae endemic to Costa Rican cloud forests with and Anthocerotae in Montane Forests of the three known localities on the mainland and Tropical Andes. In: S. P. Churchill, H. .L occurring also on Cocos Island, where it is very Balslev, E. Forero & J. L. Luteyn (eds.), common (Dauphin, 1999). The rare endemic Biodiversity and Conservation of Nowellia reedii Robins., described from Neotropical Montane Forests, p. 32 1-354. Monteverde (exact locality unknown) and not New York Botanical Garden. Diversity and habitat differentiation of mosses GRADSTEIN,S. R. & P&s, T. 1989. Bryophytes. NADKARNI,N. & T. J. MATELSON.1992. In: H. Lieth & M. J. A. Werger (eds.), Tro- Biomass and nutrient dynamics of epiphytic pical Rainforest Ecosystems, p. 31 1-325. litterfall dynamics in a neotropical montane Elsevier, Amsterdam. forest, Costa Rica. Biotropica 24: 24-30. GRADSTEIN,S.R., A. LUCKING,M. I. MORALES NADKARNI,N. & N. T. WHEELWRIGHT(eds.) & G. DAUPHIN,1994. Additions to the 1999. Monteverde: Ecology and Conser- hepatic flora of CostaRica. Lindbergia 19: vation of a Tropical Cloud Forest. Oxford 73-86. University Press, New York. GRADSTEIN,S. R., P. HIETZ,R. LUCKING,A. REED,C. R. & H. ROBINSON1971. Bryophytes LUCKING,H. J. M. SIPMAN,H. F. M. VESTER, of Monteverde, Costa Rica. Phytologia 21 : J. H. D. WOLF& E. GARDETTE1996. How 6-1. to sample the epiphytic diversity of tropi- RICHARDS,P. W. 1984. The ecology of tropical cal rain forests. Ecotropica 2: 59-72. forest bryophytes. In: R. M. Schuster (ed.), GRADSTEIN,S. R., S. P. CHURCHILL& N. New Manual ofBryology Vol. 2, pp. 1233- SALAZARALLEN (in press). A Guide to the 1270. Bryophytes of Tropical America. Memoirs SILLETT,S. C., S. R. GRADSTEIN& D. GRlFFlN of the New York Botanical Garden 86. 111 1995. Bryophyte diversity of Ficus tree INGRAM,S. W. & N. NADKARNI1993. Compo- crowns from intact clouct forest and pasture sition and distribution of epiphytic organic in Costa Rica. The Bryologist 98: 251-260. matter in a neotropical cloud forest, Costa WOLF,J. H. W. 1993. Diversity patterns and Rica. Biotropica 24: 24-30. biomass of epiphytic bryophytes and lichens NADKARNI,N. 1986. An ecological overview along an altitudinal gradient in the northern and checklist of epiphytes of the Monte- Andes. Annals of the Missouri Botanical verde Cloud Forest Reserve. Brenesia 9: Garden 80: 928-960. 247-252.

Recibido: septiernbre 812000 Aceptada: dicie~nbre10/2000