Catherine La Farge

Phylogenetic relationships within the haplolepideous mosses

Abstract Mosses with haplolepideous peristomes form a major lineage within the arthrodontous taxa, the Dicranidae. Relationships among lineages within the Dicranidae are explored using three cpDNA regions: rbcL, rps4, and the region spanning trnL(UAA)- trnF(GAA). Maximum parsimony analyses of combined data sets support robust clades that correspond to traditionally recognized families. Phylogenetic relationships of 71 exemplar taxa rooted with five outgroup taxa identify 13 major clades within the Dicranidae. Predominantly the monophyly of these groups is strongly supported, although relationships among the clades are ambiguous. The phylogenetic implications of the current taxon sampling include 1) the Dicranidae are monophyletic, 2) the Pottiales are polyphyletic with the Calymperaceae and Octoblepharaceae cladistically distant from the Pottiaceae, and these two former families should be transferred to the Dicranales, 3) the Dicranales are polyphyletic, with Ditrichaceae and Rhabdoweisiaceae more closely related to the Pottiaceae than other members of the Dicranales, 4) the Fissidentaceae are nested within the Dicranales, 5) the Rhachitheciaceae and Erpodiaceae are nested within the Dicranidae and sister to the Pottiaceae, 6) Amphidium is sister to the pottiaceous clade, 7) the Seligeriaceae form a well supported sister relationship to the Grimmiales, and 8) Scouleria aquatica, Bryoxiphium norvegicum, Ditrichum flexicaule, and Timmiella crassinervis appear to form basal lineages within the Dicranidae.

Regeneration of Little Ice Age bryophytes emerging from a polar glacier with implications of totipotency in extreme environments

Across the Canadian Arctic Archipelago, widespread ice retreat during the 20th century has sharply accelerated since 2004. In Sverdrup Pass, central Ellesmere Island, rapid glacier retreat is exposing intact plant communities whose radiocarbon dates demonstrate entombment during the Little Ice Age (1550–1850 AD). The exhumed bryophyte assemblages have exceptional structural integrity (i.e., setae, stem structures, leaf hair points) and have remarkable species richness (60 of 144 extant taxa in Sverdrup Pass). Although the populations are often discolored (blackened), some have developed green stem apices or lateral branches suggesting in vivo regrowth. To test their biological viability, Little Ice Age populations emerging from the ice margin were collected for in vitro growth experiments. Our results include a unique successful regeneration of subglacial bryophytes following 400 y of ice entombment. This finding demonstrates the totipotent capacity of bryophytes, the ability of a cell to dedifferentiate into a meristematic state (analogous to stem cells) and develop a new plant. In polar ecosystems, regrowth of bryophyte tissue buried by ice for 400 y significantly expands our understanding of their role in recolonization of polar landscapes (past or present). Regeneration of subglacial bryophytes broadens the concept of Ice Age refugia, traditionally confined to survival of land plants to sites above and beyond glacier margins. Our results emphasize the unrecognized resilience of bryophytes, which are commonly overlooked vis-a-vis their contribution to the establishment, colonization, and maintenance of polar terrestrial ecosystems.

The Circumscription of the Dicranaceae (Bryopsida) Based on the Chloroplast Regions trnL—trnF and rps4

Abstract The Dicranaceae have been classified as one of the largest, most heterogeneous families of the moss subclass Dicranidae. Circumscriptions of the family have varied, with some studies excluding selected subfamilies and recognizing them at the familial rank, whereas others have retained a broader familial concept. As well, classifications have varied in their generic circumscriptions of the subfamilies. Chloroplast DNA sequence data (trnL (UAA)—trnF (GAA) and rps4) were used to examine the monophyly of the family and phylogenetic relationships among the subfamilial and generic taxa. Special emphasis was given to subfamily Dicranoideae, with 18 of the 23 genera sampled. Seventy-four trnL-F and rps4 sequences formed a matrix of 1161 aligned base pairs (bp). Phylogenetic analyses using MP and ML criteria were based on 983 bp (333 parsimony informative) after ambiguous data were removed. Our results support the following inferences: 1) Dicranaceae as traditionally defined are polyphyletic; 2) subfamilies Campylopodioideae, Dicranelloideae, Rhabdoweisioideae, and Trematodontoideae are excluded from a robust monophyletic concept of the Dicranaceae; 3) subfamily Dicranoideae is polyphyletic unless 16 genera are excluded from the subfamily, seven of which are transferred to the Rhabdoweisiaceae; 3) subfamily Paraleucobryoideae is polyphyletic with Brothera resolved in the Leucobryaceae clade and Paraleucobryum nested within subfamily Dicranoideae; 4) Dicnemonaceae (including Mesotus) and Wardiaceae are nested within traditional members of the Dicranaceae; and 5) four clades—Dicranoideae, Mesotoideae, Dicranoloma group plus Wardia, and the Leucoloma group, form a robust monophyletic taxon, considered here as a restricted concept of Dicranaceae (sensu stricto). This circumscription excludes 18 genera that have previously been included in the Dicranaceae. Communicating Editor: Alan T. Whittemore

Bryophytes as Heavy Metal Biomonitors in the Canadian High Arctic

Abstract Mosses are a major component of the tundra flora in the Canadian Arctic, yet their use in arctic contaminant research is lacking. Biomonitoring of atmospheric heavy metal deposition using mosses has been extensively employed in Europe, providing a higher sampling density than precipitation monitoring. Temporal, spatial, and habitat gradients of concentrations and enrichment factors of As, Cd, Cr, Cu, Ni, Zn, and Pb (and its stable isotopes) in mosses from Ellesmere Island are examined. Anthropogenically influenced concentrations of As, Cr, Cu, Ni, and Zn in samples collected in 2007 were observed. Concentrations of heavy metals in hydric taxa were larger than those observed in xeric or mesic taxa, though non-significant. Generally, heavy metal concentrations decreased from 1983 to 2007 in a single high arctic locality, though non-significant. Pb-isotope ratios were radiogenic and characteristic of the High Arctic Islands. Trends in high arctic moss data corresponded with environmental proxies such as glacial ice cores, lake sediments, and atmospheric aerosols illustrating the usefulness of bryophytes as biomonitors. This paper outlines the utility of using mosses as biomonitors of heavy metal depositions in the Canadian High Arctic.

Leucoloma I: A Revision of Subgenus Leucoloma (Dicranaceae, Bryopsida) in Africa and Madagascar

The following paper represents one of a series on the current status of the tropical genus Leucoloma Brid. The first portion of the paper summarizes the morphological characters of the genus to set the foundation for the revision of Subgenus Leucoloma. Two additional papers on Leucoloma are found in this volume of THE BRYOLOGIST. The results presented here incorporate the phylogenetic and biogeographic analyses that have been published previously (La Farge-England 1998). The focus of this paper is the revision of Leucoloma subgenus Leucoloma in Africa and Madagascar. This includes a revision of 25 species, including two new species, two new subspecific taxa, and one new combination (Leucoloma madagascariense sp. nov., L. membranaceum sp. nov., L. chrysobasilare ssp. africana ssp. nov., L. ochrobasilare ssp. longifolium comb. nov., L. zuluense var. ovatum var. nov.), new synonymy, a key to species and subspecific taxa, distribution maps, and illustrations of each species.The following paper represents one of a series on the current status of the tropical genus Leucoloma Brid. The first portion of the paper summarizes the morphological characters of the genus to set the foundation for the revision of Subgenus Leucoloma. Two additional papers on Leucoloma are found in this volume of THE BRYOLOGIST. The results presented here incorporate the phylogenetic and biogeographic analyses that have been published previously (La FargeEngland 1998). The focus of this paper is the revision of Leucoloma subgenus Leucoloma in Africa and Madagascar. This includes a revision of 25 species, including two new species, two new subspecific taxa, and one new combination (Leucoloma madagascariense sp. nov., L. membranaceum sp. nov., L. chrysobasilare ssp. africana ssp. nov., L. ochrobasilare ssp. longifolium comb. nov., L. zuluense var. ovatum var. nov.), new synonymy, a key to species and subspecific taxa, distribution maps, and illustrations of each species. Bryophytes are a pervasive, yet largely unstudied component of the epiphytic biomass in tropical rainforests. The role of the epiphytic bryophytes includes humus accumulation, rainfall interception, and retention as well as trapping and provision of nutrients that modify the physical habitat for successive epiphytes (i.e., orchids, ferns). Forest destruction threatens these rich epiphytic floras (Campbell 1990). A call for concentrated research on the biodiversity of rapidly disappearing, tropical ecosystems was emphasized at the Earth Summit in Sao Paulo in 1992. The document on the Convention on Biological Diversity stressed the need for protection of global biodiversity as one of the critical resources for man. Systematic research is essential to provide fundamental data for many other disciplines (i.e., agriculture, biodiversity, conservation, ecology, evolution, genetics, and medicine). Campbell (1990) designated Madagascar as one of ‘‘the greatest priority for conservation and biological inventory on Earth’’. Based on O’Shea (1997) the moss flora of Madagascar has been estimated at 752 species. The second largest moss genus of Madagascar is Leucoloma, a member of the Dicranaceae. The genus is pantropical, with its center of species richness in Madagascar and the East African Islands and forms a major component of the epiphytic biomass in the montane rainforests of these regions (La Farge-England 1998; Pócs 1980). Nearly 70% of the species are found in the African region, and nearly 50% are endemic to Madagascar and the East African Islands. Therefore, the African region has formed the initial focus of a global revision of the genus. As part of the generic revision of Leucoloma, 112 species were assessed for 60 morphological characters and subsequently grouped into 14 infrageneric taxa. A phylogenetic analysis of these groups provided a new infrageneric classification based on synapomorphies (La Farge-England 1998). Nomenclatural novelties and synonymy were provided with a key to the genus and infrageneric taxa, as well, a phytogeographic analysis of the infrageneric taxa examined the distribution of species richness and endemism in the genus. The current synopsis of the genus includes three papers 510 [VOL. 105 THE BRYOLOGIST in this volume of THE BRYOLOGIST. The first and current paper gives a historical perspective of the genus, a general discussion of generic characters, followed by a species revision of subgenus Leucoloma for the African-Malagasy region. The second is the revision of a small, but unique taxon of subgenus Syncratodictyon (La Farge 2002a). The third is an annotated list of all valid species of the genus including typification and current synonymy (La Farge 2002b). The complete species revision of the genus will be published as a continued series of taxonomic treatments. HISTORICAL PERSPECTIVE The genus Leucoloma Brid. was originally described in 1827 as a monotypic genus, based on L. bifidum (Brid.) Brid. from Réunion. Initially Bridel (1801) had described and classified this species in a diplolepideous, pleurocarpous genus, Hypnum, even though Hedwig (1782) had described the more closely related genus Dicranum (haplolepideous, acrocarpous). The preliminary placement of the species in Hypnum was not without some doubt (Bridel 1801). In notes following the generic description, Bridel (1827) compared the atypical, lateral sporophytes of Leucoloma to those of Trichostomum. He had observed that the perichaetia are initially terminal and become displaced laterally by subapical innovations. Bridel interpreted the sporophytes as lateral and classified Leucoloma among the pleurocarpous genera, not recognizing it as a prostrate acrocarp. This has been a recurrent misinterpretation of prostrate acrocarpous mosses in the literature (La Farge-England 1996). The orthographic roots of the genus Leucoloma is based on two Greek root words: leucorefers to white and lomato border. The genus was originally distinguished by the following characters 1) differentiated hyaline border; 2) single peristome of 16 teeth, bifid to the base; 3) symmetric capsule without an annulus; 4) presumed dioicous sexual condition (male plants not seen); 5) ‘‘axillary’’ female gametangia, with about 12 archegonia with paraphyses; 6) long, slender, and moderately branched habit; 7) leaves costate, narrow, and with subquadrate cell areolation; and 8) capsule erect, oblong, with a short seta and subulate operculum. The genus was described as having a southern distribution within the tropics, growing on trees as perennials (Bridel 1827). Müller (1848) followed Bridel’s classification of primarily acrocarpous versus pleurocarpous taxa (Bridel 1826, 1827), but reclassified Leucoloma as a section within a broad concept of the acrocarpous genus Dicranum. He included five sections within Dicranum: Dicranum, Campylopus, Leucoloma, Oncophorus, and Orthodicranum. The first four have been accepted as independent genera and the last has been treated at the generic or subgeneric rank by various authors (Brotherus 1924; Bruch et al. 1836–1855; Crosby & Magill 1981; Crum & Anderson 1981; Dixon 1932; Nyholm 1954; Peterson 1979; Vitt 1984). Müller placed seven species in Dicranum section Leucoloma, including Dicranum sieberianum, which is currently recognized in a distinct genus, Sclerodontium Schwaegr. (Table 1). Mitten (1859) proposed a new classification of mosses based on peristome structure in his East Indian flora including the divisions ‘‘Arthrodonti’’ and ‘‘Nematodonti’’ as subdivisions of suborder Stegocarpi. Leucoloma was classified within the arthrodontous mosses of the Dicranaceae, supporting Müller’s interpretation of Leucoloma’s affiliation with Dicranum. In a floristic treatment of Neotropical material, Mitten (1869) placed a single species in Bridel’s genus Leucoloma and described a new genus Poecilophyllum with nine species without designating the type (Table 1). Poecilophyllum was typified with Poecilophyllum serrulatum (Brid.) Mitt. as the lectotype (La Farge-England 1998). Mitten had differentiated Poecilophyllum from Leucoloma by seta length, capsule shape, and calyptra type (cucullate versus mitrate), yet had placed L. mollissimum in Leucoloma and L. serrulatum in Poecilophyllum; the two species are heterotypic synonyms. From the species that Mitten listed under Poecilophyllum the distinction between the two genera is not clear, since the one species he listed for Leucoloma is synonymous with two species he listed for Poecilophyllum, as well he listed a species that I consider a member of Dicranoloma. In a moss flora of Réunion and the other East African islands, Bescherelle (1878) used a broad concept of Leucoloma at the time, following Jaeger and Sauerbeck (1872). He did not use Mitten’s Neotropical genus, Poecilophyllum, but described five sections within Leucoloma that established the first subgeneric classification of the genus (Table 1). In Renauld’s regional flora of Madagascar, the Mascarenes and the Comoros the generic concept of Leucoloma was expanded and subdivided into three subgenera: Dicnemoloma, Dicranoloma, and Euleucoloma (Renauld 1898). The circumscription of L. subgenus Euleucoloma was based on a synopsis of 42 species. Renauld (1898) expanded and refined the classification of this subgenus to include 13 infrageneric taxa of Leucoloma (Table 1). In addition to its systematic value, Renauld’s regional study provides critical information on collectors and locality data that is otherwise lacking on the type specimens. Paris (1900) reclassified the subgenera Dicnemoloma and Dicranoloma as sections within Leu2002] 511 LA FARGE: LEUCOLOMA I T A B L E 1. H is to ri ca l re vi ew of L eu co lo m a– a ch ro no lo gi ca l li st of in fr ag en er ic ta xa .

Leucoloma III: A Species Synopsis: Typification, Synonymy, and Excluded Names

The current synopsis of Leucoloma Brid. nom. cons. is an annotated list of the accepted names that includes nomenclatural novelties, type citations, protologue data, and synonyms. The list includes 131 taxa with 118 synonyms. No type material was seen for five species and two varieties. One species is listed as a nomen nudum until the necessary nomenclatural changes can be made and is included here for completion sake. Another species is tranferred to Dicranoloma with two synonyms, whereas two species previously described as Dicranoloma species are transferred here to Leucoloma [Leucoloma onraedtii (Biz.) La Farge, comb. nov. and Leucoloma entabiense (Magill) La Farge comb. nov.]. A condensed alphabetical list of species, subspecies, varieties, and forms provide a ready reference for all accepted names and synonymy currently in Leucoloma. Each taxon has its subgeneric placement indicated. An additional alphabetical list of 106 excluded taxa with generic placement is included for a nomenclatural synopsis of Leucoloma.The current synopsis of Leucoloma Brid. nom. cons. is an annotated list of the accepted names that includes nomenclatural novelties, type citations, protologue data, and synonyms. The list includes 131 taxa with 118 synonyms. No type material was seen for five species and two varieties. One species is listed as a nomen nudum until the necessary nomenclatural changes can be made and is included here for completion sake. Another species is tranferred to Dicranoloma with two synonyms, whereas two species previously described as Dicranoloma species are transferred here to Leucoloma [Leucoloma onraedtii (Biz.) La Farge, comb. nov. and Leucoloma entabiense (Magill) La Farge comb. nov.]. A condensed alphabetical list of species, subspecies, varieties, and forms provide a ready reference for all accepted names and synonymy currently in Leucoloma. Each taxon has its subgeneric placement indicated. An additional alphabetical list of 106 excluded taxa with generic placement is included for a nomenclatural synopsis

Leucoloma II: A Revision of Leucoloma Series Holomitrioidea (Dicranaceae)

The current study is a revision of Leucoloma Brid. Subgenus Syncratodictyon Series Holomitrioidea (Ren.) La Farge-England that includes two new species–Leucoloma circinale La Farge sp. nov., endemic to Tanzania and Leucoloma marojeziense La Farge sp. nov., an endemic from the massif of Marojezy in northeastern Madagascar. The series includes four species that are characterized by having hyaline margins restricted to the lower portion of the leaf; differentiated, bulging, scalariform alar cells; strongly contorted, apiculate leaves; unusual biseriate papillae formation; and sharply differentiated, sinuose upper cells, with the basal cells extending up along the margins. The species are endemic to the lowland to elfin rainforests of Madagascar, East African Islands, and East African montane forests of central Tanzania. The phylogenetic and phytogeographic relationships of Series Holomitrioidea have been considered elsewhere (La Farge-England 1998). Renauld (1898) published a moss flora of Madagascar and the surrounding Mascarene Islands that included the genus Leucoloma Brid. In this flora he described Leucoloma Subsection Holomitrioidea within Section Transmutantia Ren. that also included five other subsections. The type species of Subsection Holomitrioidea is L. cuneifolium (Hpe. ex Müll. Hal. et Geheeb) Wright. Renauld included a second species, L. holomitrioides Müll. Hal. in Wright, based solely on the suggestive, specific epithet, although he had not seen material. The placement of the subsection within Section Transmutantia was based on papillose juxtacostal cells that end in the middle of the leaf with a large, smooth basal region below. As for sporophyte material, he had only seen a broken seta. The subsection was compared and named after the genus Holomitrium that has African species with similar leaf habits, with the subgenera Dicranoloma and Dicnemoloma removed as separate genera, Section Transmutantia was raised to subgenus rank, Subgenus Syncratodictyon (Renauld 1901). At the section rank Holomitrioidea (Ren.) Ren. was circumscribed as a monotypic taxon (Renauld 1909). In 1950, Potier de la Varde described the new monotypic section Racomitrioidea within Subgenus Syncratodictyon, based on his new species Leucoloma grimmioides P. Vard. As with Holomitrioidea, Potier de la Varde compared and named the new taxon for its resemblance to a previously described genus, Racomitrium. He justified its placement within Leucoloma Subgenus Syncratodictyon based on its differentiated alar cells and hyaline margin that extends from the base to mid-leaf, and decided a new section was warranted. Section Rhacomitrioidea was described for plants that are small-sized with an aspect suggestive of Grimmia; concave and tubulose leaves with a pointed entire acumen; membranous laminal cells restricted to the lower basal region; and chlorophyllose cells having very low papillae and a ‘‘rhacomitrioid’’ aspect (Potier de la Varde 1950). Examination of available material showed that Leucoloma cuneifolium and L. grimmioides are closely related and share a number of characters. These include apiculate leaves with sharply differentiated, papillose, sinuose, chlorophyllose upper cells from smooth, non-chlorophyllose, linear basal cells and striking papillae formation. The papillae develop as biseriate rows on a single cell that are coalescent over the walls of adjacent cells, creating a ‘‘groove’’ over the cell lumen in transverse section. Therefore, Section Rhacomitrioidea was synonymized with Section Holomitrioidea (La FargeEngland 1998). Phylogenetic analyses of morphological data supported a classification that further changed the rank to Series Holomitrioidea (Ren.) La Farge-England (La Farge-England 1998). Series Holomitrioidea is revised here to include four species, two of which are new. A key to the Series and the species members is provided below. (For a review of the general morphological characters of Leucoloma with a revision of the African-Malagasy species of L. Subgenus Leucoloma and an annotated list of species for the world, see La Farge 2002a, 2002b.) MATERIALS AND METHODS All available material from 56 institutional and private herbaria was examined for potential specimens of Leu592 [VOL. 105 THE BRYOLOGIST coloma series Holomitrioidea. Fieldwork in Tanzania and Madagascar in 1990 and 1994 provided additional material for poorly collected species, and facilitated the discovery of a new species not previously collected. Standard taxonomic methods were used for measurements, illustrations, and scanning electron micrographs in the revision (see La Farge 2002a). For type specimens found in herbaria with collections physically separated from the main collection, abbreviations are used to locate the specimens: PC-Besch. (Hb. Bescherelle), PC-PV (Hb. Potier de la Varde), PC-Th. (Hb. Thériot), FH-Fl. (Hb. Fleischer), FH-Bart. (Hb. Bartram). In PC, Cardot’s and Renauld’s herbaria have been collated with the general collections and are indicated here as PC. Representative species from each section of Leucoloma were tested with a 2% KOH solution (Zander 1993) for a color reaction. A positive yellow color reaction indicates the presence of phenolic compounds with one or no hydroxyl groups (Zander 1993). All species in Series Holomitrioidea produced a strong orange-brown color reaction in the non-chlorophyllose basal cells. KEY TO THE SUBGENERA OF LEUCOLOMA, INFRAGENERIC TAXA OF SUBGENUS SYNCRATODICTYON, AND SPECIES OF LEUCOLOMA SERIES HOLOMITRIOIDEA (Note: Taxa in parentheses are not treated here.) 1. Alar region 3–20 cells wide; alar cells thin-walled and inflated, equally thickened and non-inflated, or longitudinally thick-walled and bulging; capsules exserted to long exserted, short to long cylindric; setae red, translucent, .4 mm long; in transverse section with several layers of thickwalled, outer cortical cells; calyptra cucullate; stems in dense to loose tufts, erect or ascending, with or without central strand, transverse section round ----------------------------2. Subgenus Syncratodictyon 1. Alar region mostly (6)10–40 cells wide; alar cells longitudinally thick-walled, flat, not bulging or inflated; capsules immersed, emergent, or shortly exserted, globose, ovoid to short cylindric; setae tan, opaque, ,3 mm long; transverse section of seta with a single layer of thick-walled, outer cortical cells; calyptra mitrate; stems in loose tufts, or gregarious, downwardly out-spreading or pendent, rarely erect, without central strand, transverse section elliptic -------------(Subgenus Leucoloma) 2. Upper leaf margins serrate, with serrations from linear, hyaline cells; costa with abaxial teeth; laminal cells with one to several isodiametric transitional cells between elongate basal cells and differentiated alar cells; alar region intermediate (10–20 cells wide); transverse section of capsule with long axis of epidermal cells perpendicular or parallel to capsule wall; peristome teeth 0.5–0.6 mm long --------------------------------------------(Section Dicranoidea) 2. Upper leaf margins entire, crenulate, serrulate, or if serrate, serrations from short laminal cells; costa with abaxial surface toothed serrulate or smooth; laminal cells lacking isodiametric transitional cells between elongate basal cells and differentiated alar cells; alar region reduced (3–9 cells wide); transverse section of capsule with long axis of epidermal cells parallel to capsule wall; peristome teeth 0.2–0.4 mm long -------------------------------------------------3 3. Distal acumen subtubulose; distal cells unipapillose or uniseriately pluripapillose with papillae centered over lumen on abaxial surface, or occasionally smooth; distal papillae commonly hooked toward apex, adaxial papillae scattered along upper costa, few if any -----------4. Section Caespitulosa 3. Distal acumen flattened or terete; distal cells rarely unipapillose or biseriately pluripapillose and equally papillose on both surfaces, scattered or over lumen; distal papillae low, dense not hooked toward apex ----------------------6. Section Holomitrioidea 4. Abaxial laminal cells pluripapillose, distinctly uniseriate; juxtacostal cells with irregular or sinuose walls; distal papillae not hooked toward apex ----------------------------(Subsection Seriata) 4. Abaxial laminal cells unipapillose; juxtacostal cells more or less quadrate or rectangular; distal papillae hooked toward apex ----------------------5 5. Leaves contorted; papillae formed in pairs at the distal end of one cell and the proximal end of the cell above it in surface view; hyaline margin not undulate, restricted to the lower 1/2–2/3 of leaf; abaxial papillae multifid and low; basal cells short (, 3:1) apex ---------------------(Subsection Caespitulosa) 5. Leaves falcate-secund or flexuose; papillae centered over lumen in surface view, not forming distinct pairs between cells; hyaline margin undulate extending to apex; abaxial papillae stellate and prominent; basal cells long (. 3:1) apex ---------------------------------------------------------------------(Subsection Albescentia) 6. Dense abaxial and adaxial papillae, biseriate at cell margins, with distinct ‘‘groove’’ or lack of thickening over cell lumen in transverse section --------------------------------------------------------7 6. Abaxial and adaxial papillae not biseriate, either scattered or centered over cell lumen in transverse section ------------------------------------------------8 7. Leaves flexuose to crispate, gradually tapered to long acumen, not apiculate; lateral juxtacostal cells grading into basal and interior cells; hyaline margin extending to apex or just below; 2% KOH solution test lacks strong orange-brown color reaction -------------------------------------(Subsection Acuminata) 7. Leaves slightly crispate or strongly contorted, abruptly or gradually tapered to long acumen with apiculate apices; lateral juxtacostal cells sharply defined from smAbstract The current study is a revision of Leucoloma Brid. Subgenus Syncratodictyon Series Holomitrioidea (Ren.) La Farge-England that includes two new species–Leucoloma circinale La Farge sp. nov., endemic to Tanzania and Leucoloma marojeziense La Farge sp. nov., an endemic from the massif of Marojezy in northeastern Madagascar. The series includes four species that are characterized by having hyaline margins restricted to the lower portion of the leaf; differentiated, bulging, scalariform alar cells; strongly contorted, apiculate leaves; unusual biseriate papillae formation; and sharply differentiated, sinuose upper cells, with the basal cells extending up along the margins. The species are endemic to the lowland to elfin rainforests of Madagascar, East African Islands, and East African montane forests of central Tanzania. The phylogenetic and phytogeographic relationships of Series Holomitrioidea have been considered elsewhere (La Farge-England 1998).

Gathering Moss: A Natural and Cultural History of Mosses

Primary Succession and Ecosystem Rehabilitation by Lawrence Walker and Roger del Moral begins with a good introduction suggesting why one would want to learn about this topic. The authors’ treatments on soils, soil development, and soil processes are excellent. They describe early colonists of bare soil sites and discuss factors that influence the rate of early succession. Many ecological and climatic factors are well described, as is the role of modeling in the study and analysis of successional processes. Modeling, experimentation, and the search for generalities are three possible tools the authors recognize for analyzing successional processes, however they focus their discussion on modeling, providing minimal dialogue on the other two methods. The universal principles and theories that guide any rehabilitation project are thoroughly covered by the authors, but few specific examples are provided. Those that are included are small in scale, generally comprised of experimental research plots or severely disturbed mining areas. While useful for those working in such dimensions, it is not representative of the large-scale rehabilitation projects frequently undertaken in western North America following wildfire. Such projects can exceed 50,000 acres in size, and are commonly greater than 10,000 acres. The U.S. Forest Service and the Bureau of Land Management spend millions of dollars each year on these types of projects, many of which are actively rehabilitated due to the presence of ‘‘transformer’’ species such as exotic annual grasses. In the Great Basin, the introduction of cheatgrass, Bromus tectorum, has drastically altered successional pathways and fire regimes. The concept of ‘‘transformer’’ species invasion and implementation of rehabilitation treatments under such conditions is not addressed, but would have provided additional relevant discussion topics. The glossary is excellent and the discussion of successional theory is thorough. However, I was disappointed that bryophytes and lichens are addressed only in broad categorical terms throughout the book. The decline of Sphagnum moss from air pollution and acid rain is discussed in brief, but few other cryptogams are directly mentioned. Many primary successional sites I am aware of have high cover of either mosses or lichens or both; however, such sites were discussed only in terms of their vascular plants. I contend that cryptogams are also capable of modifying a sites’ microclimate sufficiently to be considered successional species. Vascular plants that serve as nurse plants are discussed, but the importance of cryptogams in this same role is not. Until the last two chapters, this book does not emphasize the concept of stochastic ecology and how it can drive succession. The authors do little to promote the more modern concept in plant ecology of ‘‘state and transition’’, though it is mentioned in the discussion of rehabilitation in Chapter 8 and in ‘‘Future Directions’’ in Chapter 9. I would not recommend this book for students. In fact, this book illustrates the need for a modern treatment on primary succession with more emphasis on the critical role of cryptogams. While it serves as a good reference on theoretical modeling of successional processes, most readers of THE BRYOLOGIST will be disappointed by the few references to cryptogams.—ROGER ROSENTRETER, Bureau of Land Management, Idaho State Office, Boise, Idaho 83709, U.S.A.

Roxanne Hastings (28 June 1956–2 June 2016), a tribute

Roxanne Hastings was known within the bryological sphere for her expertise on the moss family Grimmiaceae. She had a broad spectrum of training in the natural sciences. Her education included a B.Sc. from the Department of Geography in 1979 and a M.Sc. in Plant Ecology in 1984 from the Department of Botany, now the Department of Biological Sciences (DBS), at the University of Alberta, Edmonton. Her Master’s work focused on soil/vegetation relationships in Arctic Canada. After completing this degree, she began research on snow dynamics in the boreal forest; however, a series of dry years made this work difficult. After taking Dale Vitt’s bryophyte course, she became interested in the biogeography of mosses. Her insightful discussions with Dale influenced his paper on the biogeography of Desmotheca (Vitt 1990). In particular, she was intrigued by the relationship between plant distribution and rock type. This interest led her to focus on Coscinodon, which she believed had species distributions related to particular types of rocks. She began a Ph.D. program with Dale at the University of Alberta and proposed to revise the genus Grimmia for North America, but soon thereafter accepted a full time position at the Provincial Museum of Alberta (PMAE) as a Curator of Botany for their herbarium. Roxy thoroughly enjoyed field-work and took numerous trips to a broad range of places in western North America, collecting Coscinodon and Grimmia. She also developed an interest in lichens, especially the genus Peltigera. She and Bernard Goffinet, while at the University of Alberta, collaborated on a revisionary project of the genus for the area. Due to her responsibilities as Curator of Botany, Roxy never formally completed her Ph.D., but remained an active researcher. Roxy was appointed Curator of Botany from 1989 to 2014 at the Provincial Museum of Alberta, now called the Royal Alberta Museum. During this tenure she was a strong advocate for the world of bryophytes, bringing them to the attention of the general public through museum exhibits, workshops and presentations, while continuing research on the Grimmiaceae of North America. Roxy worked closely with Henk Greven on the Grimmia treatment for the Flora of North America to ensure the European and North American concepts were coordinated. She also coauthored the Grimmiaceae key for the flora with Ryszard Ochyra. Her research included contributions to the Flora of California, Pacific Northwest, the U.S. Southwest, and the flora of South America. She instigated research at the Alberta Provincial Museum to include bryophytes and lichens and helped develop a database for the PMAE’s collection, which includes over 100,000 cryptogamic specimens. She helped spearhead the incorporation of an important provincial collection from the University of Calgary (UAC) cryptogamic herbarium consisting of early Albertan bryophyte and lichen collections by Dr. Charles Bird. Upon retirement in the fall of 2014, Roxy became a Visiting Scholar at the Cryptogamic Herbarium, Department of Biological Sciences, University of Alberta, Edmonton, allowing more time dedicated to research and to complete ongoing projects on the Grimmiaceae. She was known by many for her incredible enthusiasm for bryophytes and, in particular, her contribution toward our understanding of the genera Grimmia and Coscinodon in North America and beyond. Grimmia stands as one of the most common and difficult genera encountered in temperate and montane ecosystems, where new species are still being described. Roxy worked recently with David Toren (Californian moss flora) and Judy Harpel (Yellowstone moss flora) on North American Grimmia treatments. Both of them 3 Corresponding author’s e-mail: clafarge@ualberta.ca DOI: 10.1639/0007-2745-119.3.298