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This is the first survey of bryophyte diversity in the mangroves of Panama. The study was done in the mangroves of Bocas del Toro Province, Panama, in September 2016 and, July, May and August 2017. Bryophytes were collected from prop or stilt roots of mangroves, the mid-lower part of the trunks and the lower branches. In areas inundated at high tide, additional samples were collected on the cortex of palms, its rootlets, other angiosperm trees and from decomposing logs. Twenty-six species of liverworts and seven of mosses were identified. The most diverse and predominant liverwort family was the Lejeuneaceae with twenty-two species and two varieties and, among the mosses, the Calymperaceae with three species. Species affinities with other tropical mangroves were analyzed and liverworts were found to be the dominant element. Among the liverworts collected, two are new reports for Panama: Ceratolejeunea confusa and Frullanoides mexicana. Additional surveys of the cryptogamic vegetation of Panamanian mangroves are urgently needed due to the accelerated deforestation caused by anthropic activities and the potential loss of important biodiversity.

Dauphin, Gregorio, Gradstein, S. Robbert, Allen, Noris Salazar (2022): Liverworts and hornworts of Barro Colorado Island, Panama. Cryptogamie, Bryologie 20 (9): 153-165, DOI: 10.5252/cryptogamie-bryologie2022v43a9, URL: http://dx.doi.org/10.5252/cryptogamie-bryologie2022v43a9

Octoblepharum peristomiruptum, a new species of moss in the family Octoblepharaceae from Panama and Brazil, is described and illustrated. The new species is characterised by plants with a reddish-purple colour particularly at the leaf bases, peristomes of eight teeth, each tooth composed of two rows of cells, fenestrate and usually completely separated at the base, strongly vertically striate-reticulate, some striations forked-like in shape. At the base of the teeth, some striations are horizontally orientated, poorly developed or absent, particularly on the cell wall that is rupturing in the separation of the vertical rows of the cells that form each tooth.

PREMISE Unique among vascular plants, some species of Selaginella have single giant chloroplasts in their epidermal or upper mesophyll cells (monoplastidy, M), varying in structure between species. Structural variants include several forms of bizonoplast with unique dimorphic ultrastructure. Better understanding of these structural variants, their prevalence, environmental correlates and phylogenetic association, has the potential to shed new light on chloroplast biology unavailable from any other plant group. METHODS The chloroplast ultrastructure of 76 Selaginella species was studied with various microscopic techniques. Environmental data for selected species and subgeneric relationships were compared against chloroplast traits. RESULTS We delineated five chloroplast categories: ME (monoplastidy in a dorsal epidermal cell), MM (monoplastidy in a mesophyll cell), OL (oligoplastidy), Mu (multiplastidy, present in the most basal species), and RC (reduced or vestigial chloroplasts). Of 44 ME species, 11 have bizonoplasts, cup-shaped (concave upper zone) or bilobed (basal hinge, a new discovery), with upper zones of parallel thylakoid membranes varying subtly between species. Monoplastidy, found in 49 species, is strongly shade associated. Bizonoplasts are only known in deep-shade species (

Plant endosymbiosis with nitrogen-fixing cyanobacteria has independently evolved in diverse plant lineages, offering a unique window to study the evolution and genetics of plant–microbe interaction. However, very few complete genomes exist for plant cyanobionts, and therefore little is known about their genomic and functional diversity. Here, we present four complete genomes of cyanobacteria isolated from bryophytes. Nanopore long-read sequencing allowed us to obtain circular contigs for all the main chromosomes and most of the plasmids. We found that despite having a low 16S rRNA sequence divergence, the four isolates exhibit considerable genome reorganizations and variation in gene content. Furthermore, three of the four isolates possess genes encoding vanadium (V)-nitrogenase (vnf), which is uncommon among diazotrophs and has not been previously reported in plant cyanobionts. In two cases, the vnf genes were found on plasmids, implying possible plasmid-mediated horizontal gene transfers. Comparative genomic analysis of vnf-containing cyanobacteria further identified a conserved gene cluster. Many genes in this cluster have not been functionally characterized and would be promising candidates for future studies to elucidate V-nitrogenase function and regulation.

Liverworts and mosses are a major component of the epiphyte flora of tropical montane forest ecosystems. Canopy access was used to analyse the distribution and vertical stratification of bryophyte epiphytes within tree crowns at nine forest sites across a 3400 m elevational gradient in Peru, from the Amazonian basin to the high Andes. The stable isotope compositions of bryophyte organic material (13C/12C and18O/16O) are associated with surface water diffusive limitations and, along with C/N content, provide a generic index for the extent of cloud immersion. From lowland to cloud forest δ13C increased from −33‰ to −27‰, while δ18O increased from 16.3‰ to 18.0‰. Epiphytic bryophyte and associated canopy soil biomass in the cloud immersion zone was estimated at up to 45 t dry mass ha−1, and overall water holding capacity was equivalent to a 20 mm precipitation event. The study emphasizes the importance of diverse bryophyte communities in sequestering carbon in threatened habitats, with stable isotope analysis allowing future elevational shifts in the cloud base associated with changes in climate to be tracked.

Based on separately obtained and analyzed molecular data and within the framework of a global revision of the family Trypetheliaceae, 21 new species are described, from the Neotropics and tropical Asia, in the genera Architrypethelium (1), Astrothelium (15), Bathelium (1), Nigrovothelium (1), Trypethelium (1), and Viridothelium (2), namely: Architrypethelium lauropaluanum Lücking, M. P. Nelsen & Marcelli sp. nov., differing from A. hyalinum in the perithecia immersed between coarse thallus verrucae and in the additional ascospore septa; Astrothelium aurantiacocinereum Lücking, Naksuwankul & Lumbsch sp. nov., differing from A. aeneum in the prominent, well-delimited, trypethelioid pseudostromata and the absence of pigment on the thallus surface, as well as in the barely lichenized thallus; A. carassense Lücking, M. P. Nelsen & Marcelli sp. nov., differing from A. purpurascens in orange, K+ red pseudostroma pigment and the slightly larger ascospores; A. cryptolucens Lücking, M. P. Nelsen & N. Salazar sp. nov., differing from A. carrascoense in the inspersed hymenium; A. fijiense Lücking, Naksuwankul & Lumbsch sp. nov., differing from A. cinereorosellum in the presence of lichexanthone on the well-delimited pseudostromata and in the slightly shorter ascospores; A. laevithallinum Lücking, M. P. Nelsen & Marcelli sp. nov., differing from A. endochryseum in the smooth thallus; A. leucosessile Lücking, M. P. Nelsen & Aptroot sp. nov., differing from A. phlyctaena in the conspicuous, sessile pseudostromata; A. macrostomoides Lücking, M. P. Nelsen & Benatti sp. nov., differing from A. macrostomum in the larger ascospores; A. megacrypticum Lücking, M. P. Nelsen & N. Salazar sp. nov., differing from A. longisporum in the single-spored asci and larger ascospores; A. nicaraguense Lücking, M. P. Nelsen & T. Orozco sp. nov., differing from A. gigantosporum in the smaller ascospores; A. norisianum Lücking, M. P. Nelsen & Aptroot sp. nov., differing from A. sepultum in the distinct, well-delimited pseudostromata; A. obtectum Lücking, M. P. Nelsen & Benatti sp. nov., differing from A. nigrocacuminum in the smaller ascospores; A. sordithecium Lücking, M. P. Nelsen & Marcelli sp. nov., differing from A. leucothelium in the inspersed hymenium and the absence of lichexanthone from the thallus surface outside the pseudostromata; A. subendochryseum Lücking, M. P. Nelsen & Marcelli sp. nov., differing from A. endochryseum in the absence of pigment in the pseudostromata and the lateral thallus cover of the pseudostromata; A. subinterjectum Lücking, M. P. Nelsen & Jungbluth sp. nov., differing from A. obtectum in the smaller pseudostromata and smaller ascospores, and from A. interjectum in the diffuse pseudostromata and smaller ascospores; Bathelium porinosporum Lücking, M. P. Nelsen & Gueidan sp. nov., differing from other Bathelium species in the 3-septate, euseptate ascospores; Nigrovothelium bullatum Lücking, Upreti & Lumbsch sp. nov., differing from N. tropicum in the bullate thallus; Trypethelium tolimense Lücking, Moncada & M. Gut. sp. nov., differing from T. xanthoplatystomum in the absence of a yellow-orange pigment on the pseudostromata and the K+ yellow (not K+ red) medullary pigment; Viridothelium tricolor Lücking, M. P. Nelsen & N. Salazar sp. nov., characterized by black perithecia with a lateral ostiole immersed in white pseudostromata strongly contrasting with the surrounding brown thallus, in combination with 2-spored asci and large, muriform ascospores; and V. vonkonratii Lücking, Naksuwankul & Lumbsch sp. nov., differing from V. virens in larger ascospores and mostly solitary ascomata. All species are illustrated and their taxonomy and phylogenetic relationships are discussed. ITS barcoding sequences are reported for five specimens of Bathelium porinosporum.

We provide an expanded and updated, 2-locus phylogeny (mtSSU, nuLSU) of the lichenized fungal family Trypetheliaceae, with a total of 196 ingroup OTUs, in order to further refine generic delimitations and species concepts in this family. As a result, the following 15 clades are recognized as separate genera, including five newly established genera: Aptrootia, Architrypethelium, Astrothelium (including the bulk of corticate species with astrothelioid ascospores; synonyms: Campylothelium, Cryptothelium, Laurera), Bathelium s. str. (excluding B. degenerans and relatives which fall into Astrothelium), the reinstated Bogoriella (for tropical, lichenized species previously placed in Mycomicrothelia), Constrictolumina gen. nov. (for tropical, lichenized species of Arthopyrenia), Dictyomeridium gen. nov. (for a subgroup of species with muriform ascospores previously placed in Polymeridium), Julella (provisionally, as the type species remains unsequenced), Marcelaria (Laurera purpurina complex), Nigrovothelium gen. nov. (for the Trypethelium tropicum group), Novomicrothelia gen. nov. (for an additional species previously placed in Mycomicrothelia), Polymeridium s. str., Pseudopyrenula, Trypethelium s. str. (T. eluteriae group), and Viridothelium gen. nov. (for the Trypethelium virens group). All recognized genera are phenotypically characterized and a discussion on the evolution of phenotypic features in the family is given. Based on the obtained phylogeny, species delimitations are revised and the importance of characters such as thallus morphology, hymenial inspersion, and secondary chemistry for taxonomic purposes is discussed, resulting in a refined species concept.

Cyathodium is a thalloid marchantialean liverwort with five species reported for the Neotropics. Three species that occur in Panama (C. bischlerianum, C. spruceanum, C. cavernarum) and one from Costa Rica (C. foetidissimum) were studied chemically. Female and male plants of the dioecious C. spruceanum were very similar in their chemical composition except for two compounds that were found only in female plants. All samples of C. spruceanum and C. bischlerianum contained, in less than three percent, the sesquiterpenes germacrene D and bicyclogermacrene. The presence of these compounds suggests a close affinity between these two species. Cyathodium bischlerianum contained mainly aromatic monoterpenes with nerolidol as the main compound. Cyathodium cavernarum also had a very distinct chemical composition with an octane derivative as its major compound. Indole compounds were found only in C. foetidissimum. The presence of these compounds in plants from Costa Rica and Tahiti suggests that they could be considered as potential chemosystematic markers for the species. Based on their chemical composition there is a clear distinction between the four species of Cyathodium studied. The chemistry of these species supports previous morphological and genetic studies. Only two compounds could be identified in Leiosporoceros dussii. There is a need for additional genetic and chemical studies on neotropical Cyathodium and Leiosporoceros. Key

We report for the first time the chemical profiling of volatile organic compounds (VOCs) of gametophyte and sporophyte life stages of Leiosporoceros dussii, from Panama by using headspace-solid phase microextraction-gas chromatography-mass spectrometry in order to assess distinguishing chemical markers between the male and female gametophytes, and sporophytes of this hornwort. A total of 27 VOCs were identified in L. dussii. Furthermore, the gametophyte and sporophyte showed clear differences in the type and amount of VOCs. The main constituents of L. dussii female thalli were menthacamphor (17.8%), hexanol (12.3%), and menthyl acetate (12.3%), while the major compounds of the male thalli were hexanol (25.3%), β-ionone (21.1%), benzeneacetaldehyde (17.6%), and β-cyclocitral (14.0%). The main VOCs of the sporophytes were hexanal (19.3%), β-cyclocitral (17.6%), 2-nonenal (15.8%), hexanol (12.5%), and β-ionone (10.2%). Unique compounds found in the female thalli were 3-pentanone, 3-octenol, nonanol, estragole, and menthyl acetate, and in the male thalli were methyl heptenone, nonanal, neoisomenthol, and bornyl acetate. Isomenthol, thymol, isomenthol acetate, and β-methylnaphthalene were only found in the sporophyte. The characteristic VOCs identified in L. dussii suggest a difference between the chemical constituents of L. dussii and other hornworts species. The presence of simple VOCs when compared with compounds previously characterized in another hornwort genera may support the distinct genetic nature of this species.

† Background and Aims There is a conspicuous increase of poikilohydric organisms (mosses, liverworts and macrolichens) with altitude in the tropics. This study addresses the hypothesis that the lack of bryophytes in the lowlands is due to high-temperature effects on the carbon balance. In particular, it is tested experimentally whether temperature responses of CO2-exchange rates would lead to higher respiratory carbon losses at night, relative to potential daily gains, in lowland compared with lower montane forests. † Methods Gas-exchange measurements were used to determine water-, light-, CO2- and temperature-response curves of net photosynthesis and dark respiration of 18 tropical bryophyte species from three altitudes (sea level, 500 m and 1200 m) in Panama. † Key Results Optimum temperatures of net photosynthesis were closely related to mean temperatures in the habitats in which the species grew at the different altitudes. The ratio of dark respiration to net photosynthesis at mean ambient night and day temperatures did not, as expected, decrease with altitude. Water-, light- and CO2-responses varied between species but not systematically with altitude. † Conclusions Drivers other than temperature-dependent metabolic rates must be more important in explaining the altitudinal gradient in bryophyte abundance. This does not discard near-zero carbon balances as a major problem for lowland species, but the main effect of temperature probably lies in increasing evaporation rates, thus restricting the time available for photosynthetic carbon gain, rather than in increasing nightly respiration rates. Since optimum temperatures for photosynthesis were so fine tuned to habitat temperatures we analysed published temperature responses of bryophyte species worldwide and found the same pattern on the large scale as we found along the tropical mountain slope we studied.

Contemporary taxonomists usually recognize a single species in Dumortiera, which is widely distributed through tropical and subtropical regions and extends into some temperate regions. Two subspecies, D. hirsuta subsp hirsuta and subsp. nepalensis, may be recognized, and both of these were thought to occur in Central America. We sequenced four loci, the nuclear internal transcribed spacer region ITS, and three chloroplast loci (rbcL, psbA-trnH and rpoC1) from 50 samples of Dumortiera across its geographic range to test for phylogenetic structure within the species and its congruence to morphological and geographic patterns. We also used light and scanning electron microscopy to examine morphological differences between accessions from Central America. Phylogenetic inferences reveal two highly distinct lineages: the first apparently restricted to Central America, and the second distributed across all the geographic regions sampled. This widespread lineage could itself be subdivided into several ge...

We report for the first time the chemical composition of volatile components (VOCs) of two subspecies, D. hirsuta subsp. hirsuta and D. hirsuta subsp. nepalensis, of the liverwort Dumortiera hirsuta from Panama by using headspace-solid phase microextraction-gas chromatography-mass spectrometry in order to assess distinguishing markers between the two species. Forty VOCs were identified in total for both subspecies. Of these, 34 are reported for the first time in D. hirsuta. Furthermore, both subspecies showed clear differences in the type and amount of VOCs. The major compounds in D. hirsuta subsp. hirsuta were α-gurjunene, β-selinene, α-guaiene, α-humulene and β-caryophyllene; while in D. hirsuta subsp. nepalensis were ledene, α-gurjunene, β-caryophyllene and α-guaiene, respectively. Two oxygenated sesquiterpenes, globulol and nerolidol, could be considered as possible distinguishing chemical markers between these two subspecies. We conclude that both morphotypes of D. hirsuta are chemically different.

A new Neotropical species of hornwort, Nothoceros superbus, is described from Costa Rica. The species is distinguished by its large size, strongly costate thallus with crispate-imperforate wings, dioicous condition and green, unicellular spores that are minutely papillose with tubercules dispersed on the borders and the distal face, and sometimes clustered in the center of the distal face. Nothoceros superbus has a combination of Megaceros-like spores and a Dendroceros-like thallus growth-form. The combination of these features supports its placement in the genus Nothoceros in the Dendrocerotaceae. Nomenclatural clarifications on Nothoceros endiviaefolius (Mont.) J. Haseg. and Nothoceros giganteus (Lehm. & Lindenb.) J. Haseg. are made. Based on new molecular and morphological data a new combination, Nothoceros canaliculatus (Pagan) comb. nov., is proposed.

Twenty eight hepatics and eight hornwort species are reported as new to Panama. Data on their habitat, local and general distribution and are included. One species, Cololejeunea panamensis G. Dauphin & Pócs is described as new to science. A new combination, Megaceros canaliculatus (Pagán) Shaw & Renzaglia, corr. et emend. J. C. Vill. & Salazar Allen, is proposed. Eight further hepatic records from the literature have been added. This raises the total number of hepatics reported from Panama to 325 species in 100 genera and 28 families.

Cyathodium foetidissimum Schiffn., an Asiatic species is reported for the first time for the Neotropics. The species is distinguished by the presence of a central multistratose area of cells; oil cells with a single oil body; strongly dimorphic rhizoids; large ventral scales; monoicous condition with an apical, male receptacle flanked by archegonia in undulate laminar involucres; an operculum of 12 cells; upper cells of the capsule with bar-like thickenings; elaters with three bands; and verrucose spores. The closest relative in habit is Cyathodium spruceanum Prosk., but plants of this species lack a “midrib” and have oil bodies and chloroplasts in the thallus cells; it is dioicous and the spores are lamellate-reticulate. Mature male plants of Cyathodium foetidissimum have been found along with bisexual thalli. This is the first report of both types of gametophytes occurring simultaneously in monoicous species of neotropical Cyathodium.

Cyathodium bischlerianum is described as a new Neotropical species from Panama. The species is distinguished by its slender, delicate thallus; a prominent dorsal pore at base of involucre; monoicous condition with 1–2 archegonia per involucre, and male receptacles on sides of thallus; sporophytes without operculum; cells of upper third of capsule with bar-like thickenings; elaters attached to base of capsule wall with 3–4 bands; and spinose-bulbose spores. This species resembles the Asiatic C. aureonitens in spore ornamentation, but its monoicous condition, lack of operculum, naked involucre, and ornamentation of upper capsule cells separate it from its Asiatic relative. It is also related in morphology, sexual condition, and spore ornamentation to C. cavernarum.

A brief account of the geography and floristic regions of Panamá is complemented with an historical account of the liverwort studies of this country. This is followed by an annotated checklist of 289 taxa, including 93 new for Panamá. Among these are four hornwort taxa that represent the first anthocerotes reported. Each checklist entry comprises proper taxon citation, collection data and/or bibliographic references.

Out of 21 species of Octoblepharum validly published for the Neotropics only 9 are recognized at the present time. These are: O. albidum Hedw., O. ampullaceum Mitt., O. cocuiense Mitt., O. cylindricum Schimp. ex Mont., O. erectifolium Mitt., O. pulvinatum (Doz. & Molk.) Mitt., O. rhaphidostegium C. Mull., O. stramineum Mitt. y O. tatei (Williams) Bartr. According to the number of peristome teeth, there are two evolutionary lines: one with 16 and the other with 8. Members of the first line are all dioicous whereas those in the latter are either autoicous or dioicous. Phenological studies in three species of Octoblepharum in Panama suggest the occurrence of pseudodioecism in autoicous species and the development of a greater number of male gametoecia and antheridia than female ones. Two peristome types are found in populations of O. albidum ; one is vertically striated while the other is smooth. All species occur in South America and this is considered the center of origin and speciation for the genus.

A bryophyte inventory along an altitudinal gradient on Cerro Pirre (1200 m), Darién National Park, Panama, demonstrates that the different rain forest types along the gradient (inundatedlowland, hillside-lowland, submontane, montane elfin forest) have very different species assemblages. The montane forest has the largest number of exclusive species and the largest bryophyte biomass. Species richness is greatest in the submontane forest. The bryophyte flora of Cerro Pirre is not exceedingly rich in species owing to the rather low elevation of the mountain and the seasonal climate in the adjacent coastal plain. Nevertheless, the distinct altitudinal diversification and the occurrence of a considerable number of rare hepatic taxa, demonstrate the importance of Darién National Park as an area of plant conservation. Forty hepatic species are reported as new to Panama.

The species of Octoblepharum occurring in Central America have been critically examined. Six are recognized as valid species: O. albidum, O. cocuiense, O. cylindricum, O. erectifolium, O. pulvinatum and O. stramineum. Synonyms are given for these species: O. longifolium = O. albidum; O. mittenii, O. fragillimum, O. pellucidum and =O. pulvinatum var. angustifolium are synonyms of O. cocuiense; O. juruense and O. densum = O. pulvinatum and O. purpureo-brunneum = O. stramineum. All species are widely distributed in the area except for O. cylindricum and O. stramineum that are known only from Belize and Panama respectively.

An axenic culture of Symphyogyna brongniartii has been initiated from spores on modified Benecke medium. Growth was best on Gam borg B5 medium with 0.3% sucrose, with a doubling time of 36 days. The culture produced the same terpenoids as plants growing in their natural habitat, perrottetianal A being the major constituent. Also found were bicyclogermacrene, β-barbatene, δ-selinene, β-cubebene, spathulenol, and (-)-geosm in . The latter compound was hitherto only known from microorganisms. Synthesis rate of terpenoids during the passage period and quantitative differences in terpenoid production on different mineral media were investigated.

The number of undescribed species of lichenized fungi has been estimated at roughly 10,000. Describing and cataloging these would take the existing number of taxonomists several decades; however, the support for taxonomy is in decline worldwide. In this paper we emphasize the dire need for taxonomic expertise in lichenology. We bring together 103 colleagues from institutions worldwide to describe a total of 100 new species of lichenized fungi, representing a wide taxonomic and geographic range. The newly described species are: Acarospora flavisparsa, A. janae, Aderkomyces thailandicus, Amandinea maritima, Ampliotrema cocosense, Anomomorpha lecanorina, A. tuberculata, Aspicilia mansourii, Bacidina sorediata, Badimia multiseptata, B. vezdana, Biatora epirotica, Buellia sulphurica, Bunodophoron pinnatum, Byssoloma spinulosum, Calopadia cinereopruinosa, C. editae, Caloplaca brownlieae, C. decipioides, C. digitaurea, C. magnussoniana, C. mereschkowskiana, C. yorkensis, Calvitimela uniseptata, Chapsa microspora, C. psoromica, C. rubropulveracea, C. thallotrema, Chiodecton pustuliferum, Cladonia mongkolsukii, Clypeopyrenis porinoides, Coccocarpia delicatula, Coenogonium flammeum, Cresponea ancistrosporelloides, Crocynia microphyllina, Dictyonema hernandezii, D. hirsutum, Diorygma microsporum, D. sticticum, Echinoplaca pernambucensis, E. schizidiifera, Eremithallus marusae, Everniastrum constictovexans, Fellhanera borbonica, Fibrillithecis sprucei, Fissurina astroisidiata, F. nigrolabiata, F. subcomparimuralis, Graphis caribica, G. cerradensis, G. itatiaiensis, G. marusa, Gyalideopsis chicaque, Gyrotrema papillatum, Harpidium gavilaniae, Hypogymnia amplexa, Hypotrachyna guatemalensis, H. indica, H. lueckingii, H. paracitrella, H. paraphyscioides, H. parasinuosa, Icmadophila eucalypti, Krogia microphylla, Lecanora mugambii, L. printzenii, L. xanthoplumosella, Lecidea lygommella, Lecidella greenii, Lempholemma corticola, Lepraria sekikaica, Lobariella sipmanii, Megalospora austropacifica, M. galapagoensis, Menegazzia endocrocea, Myriotrema endoflavescens, Ocellularia albobullata, O. vizcayensis, Ochrolechia insularis, Opegrapha viridipruinosa, Pannaria phyllidiata, Parmelia asiatica, Pertusaria conspersa, Phlyctis psoromica, Placopsis imshaugii, Platismatia wheeleri, Porina huainamdungensis, Ramalina hyrcana, R. stoffersii, Relicina colombiana, Rhizocarpon diploschistidina, Sticta venosa, Sagenidiopsis isidiata, Tapellaria albomarginata, Thelotrema fijiense, Tricharia nigriuncinata, Usnea galapagona, U. pallidocarpa, Verrucaria rhizicola, and Xanthomendoza rosmarieae. In addition, three new combinations are proposed: Fibrillithecis dehiscens, Lobariella botryoides, and Lobariella pallida.

Syrrhopodon simmondsii Steere is reported new to Panama and Central America on a specimen collected on Barro Colorado Island, Panama. During a recent trip related to the survey of the hepatics of Barro Colorado Island, I (with S. R. Gradstein) collected a sample of a limbate Syrrho- podon on protruding roots of a tree on Balboa Trail, 500-600 m (stakes 5-6) from the beginning of the trail (SalazarA. & Gradstein 15126, PMA). Two lim- bate species of Syrrhopodon have been previously reported for the Island (Salazar Allen et al. 1991): S. gaudichaudii Mont. and S. parasiticus (Brid.) Besch. Nevertheless, the specimen found was very different from these species in that the leaves bore prominent short marginal cilia at the shoulders, the plants were very small (perhaps one reason why it has been overlooked in previous surveys) growing in dispersed turfs, and rhizoids were purple-red. A close examination of the plants under the micro- scope and comparisons with herbarium duplicates of limbate species of Syrrhopodon from Central and South America indicated that the specimen was S. simmondsii Steere, described by Reese (1993) as an endemic species of northern South America. The plants were growing intermixed with the moss Oc- toblepharum albidum Hedw. and the leafy liverwort Pictolejeunea picta (Gott. ex Steph.) Grolle. With this new report, the geographical range of the species is amplified to include Panama. It is most probable that it also occurs in other areas of Central America. In relation to habitat, Reese (1987) has indicated that the majority of Syrrhopodon species appear to be plants of warm, humid lowlands. The localities from which S. simmondsii have been previously reported and the one at Barro Colorado Island fit well with this habitat definition. Other bryophytes that grow in similar habitats are, e.g., the leafy liv- erworts Radula macrostachya Lindenb. & Gott., Pictolejeunea picta, and the mosses Calymperes ero- sum C. Miill., C. palisotii Schwaegr., Octoblephar- um albidum, Pilosium chlorophyllum (Hornsch.) C. Miill., and Taxithelium planum (Brid.) Mitt.

Eighty-one species of mosses are reported for Barro Colorado Island. The most im- portant families in number of species are Hookeriaceae (17 spp.), Fissidentaceae (12 spp.), Calym- peraceae (11 spp.), Pterobryaceae (6 spp.), Sematophyllaceae (6 spp.), Neckeraceae (5 spp.), Hyp- naceae (5 spp.), and Meteoriaceae (5 spp.). Pleurocarpous forms predominate with equal numbers of Hypnobryales, Isobryales, and Hookeriales. The flora of the Isthmus, and thus of the Island, reflects the recent geological history of Panama and is considered to be derived from the already diverse moss flora of adjacent land masses. Barro Colorado Island is an internationally known tropical research center located in the Panama Ca- nal area, 9"09'N, 79*51'W, halfway between the Pa- cific and Atlantic oceans (Fig. 1). With an area of

Bryum incrassatolimbatum Card. is reported new to Panama and its sporophytes are described and illustrated for the first time. This moss appears to be most closely allied to B. cellulare Hook., based on the morphology of the capsule. Since the original description by Cardot (1909), based on sterile material from Mexico, the taxo- nomic status of Bryum incrassatolimbatum has been uncertain (Ochi 1980; Shaw 1981). Its distributional range has been extended to Oklahoma and Arizona in the United States (Shaw 1981). Plants of this species with sporophytes are here reported for the first time from Panama and a description of the sporophyte is provided (Fig. 1-6).

Collecting permits are given by the Departamento de Parques Nacionales y Vida Silvestre. Apartado 2016, Paraíso, Ancón. Panamá. República de Panamá. The request must include location of the area in which the study is to be conducted, duration, names of the species to be studied when applicable.

Leucophanes is a genus of mainly palaeotropical turf forming mosses. Populations consist of acrocarpous, branched or unbranched gametophores. In the latter, the turfs are formed by layers of individual plants each attached by rhizoids to the plant beneath it. These fully grown epigametophytic plants are of the same gender as the supporting plant. It is suggested that this particular growth habit is an adaptation to continue turf existence by the development of various strategies of vegetative reproduction, e.g., germination of leaf tip gemmae and readily detachable short branching systems. This is of importance in species for which sexual reproduction has not been demonstrated and which have few or no subterminal innovations. Growth habit and structural features displayed by the gametophytes of Leucophanes are also adaptations for water retention. It is most likely that the life-form characteristic of this genus developed in relation to environmental stresses imposed by the corticolous habit in seasonally dry tropical forests. The genus Leucophanes, with 41 valid names, is widely distributed in tropical and subtropical areas of the Old World (Wijk et al. 1964; Gangulee 1971). Three species have been reported for the Neotropics (Wijk et al. 1964). The genus is composed of acrocarpous, cortico- lous mosses, characterized by the structure of the leaf, analogous to that of Leucobryum, with a central layer of chlorophyllous cells surrounded on each surface, by one or more layers of porose hyalocysts (Fig. 1-3). A single costa runs the length of the leaf. About 90% of the species develop gemmae (Fig. 4, 5) and all produce rhizoids at the apex of the leaves. The plants grow in turfs of variable sizes on rotten logs, and the trunks, branches and bases of trees. Most species are dioicous with male and female plants structurally similar. One species, L. serra- tulum Fleisch., is synoicous. In some species, L. calymperatum C. Mill., L. brasiliense Broth., L. rodriguezii C. Mill. and L. unguiculatum Mitt. only female plants are known.

Development of rhizoidal heads in Leucobryum martianumfrom Cerro Jefe, Panama, is reported for the first time. Leucobryum martianum (Hornsch.) Hampe is a moss species distributed throughout tropical Amer- ica. It grows in forests of low to high altitudes. In Panama, it occurs from sea level to elevations of over 1,000 m. The plants, 2-3 cm in height, grow in dense to loose turfs; the leaves are erect-crowded and falcate to falcate-secund. Like many other species of Leucobryum (Crum & Anderson 1981; Crum & Steere 1957), the leaves can serve as asexual dia- spores. Crum (1976) and Crum and Anderson (1981) have reported growth of rhizoids at the tips of leaves of Leucobryum glaucum (Hedw.) Angstr., suggesting that this character may be indicative of high poten- tialities for establishment of new plants from leaf fragments after dispersal. Production of rhizoids from leaves is of common occurrence in various