Selaginella P.Beauv. (Selaginellaceae) in the state of Maranhão, northeastern, Brazil: A floristic survey and a new record for the Cerrado domain / Selaginella P.Beauv. (Selaginellaceae) no estado do Maranhão, nordeste, Brasil: Levantamento florístico e novo registro para o domínio Cerrado

Abstract This work is a floristic study of Selaginella in Maranhão. The species survey is based on collections from fieldwork conducted between April 2006 and February 2023 and specimens from Maranhão deposited at the CCAA, HBRA, MG, and SLUI herbaria. Ten species were identified: Selaginella conduplicata, S. convoluta, S. erythropus, S. flagellata, S. gynostachya S. marginata, S. minima, S. radiata, S. simplex, and S. sulcata. We report the first record of S. gynostachya for Maranhão and the Cerrado domain in Brazil. Until now, this species was only known from areas of Amazonia. We provide a map with records, an identification key, and comments about the identification and geographic distribution of Selaginella species in Maranhão state. For the new record, we also provide photos.

Resumo O presente trabalho trata do estudo florístico de Selaginella no Maranhão. O levantamento de espécies foi realizado com base em coletas de campo realizadas entre abril de 2006 e fevereiro de 2023 e em análise de espécimes coletados no Maranhão e depositadas nos herbários CCAA, HBRA, MG e SLUI. Foram identificadas 10 espécies: Selaginella conduplicata, S. convoluta, S. erythropus, S. flagellata, S. gynostachya S. marginata, S. minima, S. radiata, S. simplex e S. sulcata. Relatamos a primeira ocorrência de S. gynostachya para o Maranhão e também para o domínio do Cerrado Brasileiro. Até então essa espécie era registrada somente em áreas amazônicas. Neste artigo apresentamos um mapa com pontos de coleta, uma chave de identificação e comentários sobre a identificação, ecologia e distribuição geográfica para as espécies de Selaginella do Maranhão. Para o novo registro apresentamos também fotos.

Taxonomic innovations in South American Selaginella (Selaginellaceae, Lycopodiophyta): description of five new species and an additional range extension.

Five Selaginella species (i.e, S. gioiae, S. papillosa, S. pubimarginata, S. rostrata, and S. xanthoneura) from Neotropical rainforests of South America are described and illustrated as new, while S. surucucusensis, originally recorded only from Brazil, is redefined to account for species' morphological characters throughout its expanded distribution range and also a novel illustration is provided for it. Inferred taxonomic affinities and conservation assessment are offered for species here treated. Selaginella gioiae is native to Colombia, Ecuador, and Peru, and S. xanthoneura is so far only known in Colombia, whereas S. surucucusensis is now known to occur in Colombia and Venezuela in the north-central part of South America. These three species are included in the "Selaginella flabellata group" based on their habit, stem shape, rhizophores position, and mega- and microspores color, and ornamentation. Selaginella papillosa, S. pubimarginata, and S. rostrata are native to Venezuela. Selaginella papillosa and S. pubimarginata morphologically belong in the "Selaginella deltoides group" based on their habit, stem type, shape of lateral leaves and their indument type distributed on upper surface of the leaf lamina. On the other hand, S. rostrata is considered to be a member of the "Selaginella microdonta group," which is centered in the Guiana Highlands, based on its habit, stem type, and leaf size and shape, and for which a key to identify species is provided. Finally, all species threated here are classified in subg. Stachygynandrum based on their heteromorphic leaves, mostly quadrangular strobili, and monomorphic sporophylls shape (except for S. rostrata that has slightly dorsiventral and flattened strobili with somewhat heteromorphic sporophylls).

ResumenSe describen e ilustran cinco nuevas especies de Selaginella (i.e, S. gioiae, S. rostrata, S. papillosa, S. pubimarginata, and S. xanthoneura) de los bosques neotropicales de Suramérica, mientras que S. surucucusensis, originalmente descrita de Brasil, es redefinida para incorporar los caracteres morfológicos de la especie a lo largo de su rango de distribución expandido y también una nueva ilustración se provee para ella. Además, se incorporan discusiones sobre las afinidades taxonómicas y el estado de conservación de las especies aquí tratadas. Selaginella gioiae es nativa de Colombia, Ecuador y Perú, y S. xanthoneura se conoce actualmente sólo de Colombia, mientras que S. surucucusensis ahora se reporta también para Colombia y Venezuela, en la región Norcentral de Suramérica. Estas tres especies se incluyen dentro del "grupo de Selaginella flabellata" debido a su hábito, tipo de tallo, posición de los rizóforos y color y ornamentación de las mega- y micrósporas. Selaginella papillosa, S. pubimarginata y S. rostrata se conocen sólo de Venezuela. Selaginella papillosa y S. pubimarginata pertenecen morfológicamente dentro del "grupo de Selaginella deltoides", en función de su hábito, tipo de tallo, forma de las hojas laterales y la clase y distribución de su indumento en la superficie superior de la lámina. Por otra parte, S. rostrata pertenece al "grupo de Selaginella nicrodonta", el cual se centra en el Escudo Guyanés y se caracteriza en función del hábito, tipo de tallo y forma y tamaño de las hojas de sus especies, las cuales pueden ser identificados mediante la clave que se provee. Finalmente, todas las especies aquí tratadas son clasificadas en el subg. Stachygynandrum, ya que poseen hojas heteromórficas, estróbilos cuadrangulares y esporofilos monomórficos (con la excepción de S. rostrata, la cual posee estróbilos ligeramente dorsiventrales y aplanados con esporofilos levemente heteromórficos).

Gigantic chloroplasts, including bizonoplasts, are common in shade-adapted species of the ancient vascular plant family Selaginellaceae.

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 (<2.1% full sunlight) of subgenus Stachygynandrum but in both the Old and New Worlds. CONCLUSIONS: Multiplastidic chloroplasts are most likely basal, implying that monoplastidy and bizonoplasts are derived traits, with monoplastidy evolving at least twice, potentially as an adaptation to low light. Although there is insufficient information to understand the adaptive significance of the numerous structural variants, they are unmatched in the vascular plants, suggesting unusual evolutionary flexibility in this ancient plant genus.

From the Guiana Highlands to the Brazilian Atlantic Rain Forest: four new species of Selaginella (Selaginellaceae - Lycopodiophyta: S. agioneuma, S. magnafornensis, S. ventricosa, and S. zartmanii).

We describe four new species in the genus Selaginella (i.e., S. agioneuma, S. magnafornensis, S. ventricosa, and S. zartmanii) from Brazil, all presently classified in subg. Stachygynandrum. For each of the new taxa we discuss taxonomic affinities and provide information on habitat, distribution, and conservation status. In addition, line drawings and scanning electron microscope (SEM) images of stems sections, leaves, and spores (when present) are included. Selaginella agioneuma and S. magnafornensis are from the State of Espíritu Santo where they inhabit premontane to montane Atlantic rain forests in the Reserva Biológica Augusto Ruschi and Parque Estadual Forno Grande, respectively. Selaginella ventricosa was collected in upper montane forests at Parque Nacional Serra da Mocidade, State of Roraima and S. zartmanii in premontane Amazon rain forests on upper Rio Negro at Mpio. São Gabriel da Cachoeira, Amazonas State in both Serra Curicuriari and the Morro dos Seis Lagos Biological Reserve.

Novel fern- and centipede-like Selaginella (Selaginellaceae) species and a new combination from South America.

Two new Selaginella species (i.e. S. altheae Valdespino and S. squamulosa Valdespino) and a novel combination [i.e. S. philipsonii (Jermy & Rankin) Valdespino] from South America are proposed. Descriptions, illustrations (line drawings and scanning electron micrographs, SEM, images), discussion on taxonomic affinities and information on habitat, distribution and phenology, as well as on conservation status are provided for each. Selaginella altheae is morphologically similar to species with erect, fern-like habit placed in the "Selaginella flabellata (L.) Spring group" as defined by Hieronymus, while S. squamulosa is allied to a species assembly with centipede-like habit here informally termed the "Selaginella vernicosa Baker group;" whereas S. philipsonii with its moss-like habit may be associated with species in the "Selaginella jungermannioides (Gaudich.) Spring group" or those centered on S. ovifolia Baker. All taxa here proposed are classified in subg. Stachygynandrum.

ResumenDos nuevas especies de Selaginella (i.e., S. altheae Valdespino y S. squamulosa Valdespino) y una nueva combinación [i.e., S. philipsonii (Jermy & Rankin) Valdespino de Sur América son propuestas. Para cada una de ellas se provee una descripción, ilustraciones (i.e. dibujos y micrografías de microscopio electrónico de barrido, MEB), discusión sobre su afinidad taxonómica, información sobre su hábitat, distribución y fenología, así como su estado de conservación. Selaginella altheae es morfológicamente similar a las especies con hábito erecto y parecidas a los helechos que se incluyen en el "grupo de Selaginella flabellata (L.) Spring" como fue definido por Hieronymus; S. squamulosa es afín a especies con hábito centipediforme que aquí informalmente se denominan "grupo de Selaginella vernicosa Baker", mientras que S. philipsonii con su hábito parecido al de los musgos puede estar emparentada con el "grupo de Selaginella jungermannioides (Gaudich.) Spring" o a las especies similares a S. ovifolia Baker. Por último, todos los taxa aquí propuestos se clasifican en el subg. Stachygynandrum.

Seven new species of Selaginellasubg.Stachygynandrum (Selaginellaceae) from Brazil and new synonyms for the genus.

We describe seven new species of Selaginellasubg.Stachygynandrum (Selaginellaalstonii, Selaginellablepharodella, Selaginellacrinita, Selaginellamucronata, Selaginellamucugensis, Selaginellasaltuicola, and Selaginellasematophylla) from Brazil and discuss their possible affinities and conservation status. Scanning electron micrographs of stem sections, leaves, and spores are provided to illustrate the new taxa. In Selaginellaalstonii and Selaginellasaltuicola vegetative growth from strobilus tips is reported and discussed. Four of the new species are from the Espinhaço Mountain Range associated with Campos Rupestres (montane savannah/rocky fields) vegetation. Three of these (i.e., Selaginellablepharodella, Selaginellacrinita, and Selaginellamucugensis) were collected in the northern part of the range in Chapada Diamantina, state of Bahia, while Selaginellaalstonii is from the southern part of the range in the state of Minas Gerais. Selaginellamucronata is found in Atlantic Rainforest vegetation in the state of Espírito Santo, whereas Selaginellasaltuicola inhabits Cerrado (tropical savannah) vegetation in the state of Mato Grosso. Selaginellasematophylla is the most widely distributed of the new species and was collected in Espírito Santo, Minas Gerais, and Rio de Janeiro states in Campos Rupestres and Atlantic Rainforest vegetation. Selaginellaalstonii occurs in rocky caves, Selaginellablepharodella, Selaginellacrinita, Selaginellamucugensis, and Selaginellasematophylla seem adapted to seasonally dry places, living on sandy or humid soils, Selaginellamucronata occupies humid, forest understory, and Selaginellasaltuicola is adapted to wet places associated with rocks or logs in waterfalls. Of the seven new species, six are considered local endemics (except for Selaginellasematophylla) because of their restricted currently known distributions to one or two localities within a single state in Brazil. Additionally, we propose new synonymy for Selaginellapalmiformis (syn. = Selaginellabahiensissubsp.manausensis, ≡ Selaginellamanausensis) and Selaginellavestiens (syn. = Selaginellafragillima); the last species is endemic to Brazil, recorded in the states of Goiás and Minas Gerais. Finally, based on literature discussed and this study, we conclude that the number of well-documented Brazilian Selaginella species is 61, of which 58 are native and three introduced and naturalized. These statistics are likely to change with further work on Selaginella from Brazil.

ResumenDescribimos siete nuevas especies de Selaginellasubg.Stachygynandrum (Selaginellaalstonii, Selaginellablepharodella, Selaginellacrinita, Selaginellamucronata, Selaginellamucugensis, Selaginellasaltuicola y Selaginellasematophylla) de Brasil y discutimos sus posibles afinidades y estado de conservación. Micrografias electrónicas de barrido de secciones de los tallos, hojas y esporas se proveen para ilustrar los nuevos taxa. Igualmente, se describe y discute el crecimiento vegetativo a partir del ápice de los estróbilos en Selaginellaalstonii y Selaginellasaltuicola. Cuatro de las especies nuevas proceden de la Cadena del Espinhaço asociadas a vegetación de Campos Rupestres (sabana montana). Tres de éstas (i.e., Selaginellablepharodella, Selaginellacrinita y Selaginellamucugensis) fueron recolectadas en la parte norteña de la Cadena del Espinhaço en la Chapada Diamantina, estado de Bahia, mientras que Selaginellaalstonii se registra para la parte sureña en el estado de Minas Gerais. Selaginellamucronata se encuentra en vegetación de Bosques Lluviosos del Atlántico en el estado de Espírito Santo, mientras que Selaginellasaltuicola habita vegetación de Cerrado (sabana tropical) en el estado de Mato Grosso. De las nuevas especies, Selaginellasematophylla es la más ampliamente distribuida y se ha recolectada en los estados de Espírito Santo, Minas Gerais y Río de Janeiro en vegetación de Campos Rupestres y Bosques Lluviosos del Atlántico. Selaginellaalstonii crece sobre rocas en cuevas, mientras que Selaginellablepharodella, Selaginellacrinita, Selaginellamucugensis y Selaginellasematophylla parecen estar adaptadas a lugares estacionalmente secos, creciendo sobre suelos arenosos o húmedos; a su vez, Selaginellamucronata crece en el sotobosque de bosques húmedos y Selaginellasaltuicola está adaptada a vivir en lugares húmedos asociada a rocas o troncos en cascadas. De las siete nuevas especies, seis son consideradas tentativamente endémicas locales (con la excepción de Selaginellasematophylla) debido a su distribución restringida a una o dos localidades dentro de un sólo estado de Brasil. Adicionalmente, proponemos nuevos sinónimos para Selaginellapalmiformis (syn. = Selaginellabahiensissubsp.manausensis, ≡ Selaginellamanausensis) y Selaginellavestiens (syn. = Selaginellafragillima), la cual se confirma como endémica de Brasil donde se registra para los estados de Goiás y Minas Gerais. Finalmente, de acuerdo con este estudio y la literatura discutida, estimamos que el número de especies brasileñas de Selaginella debidamente documentadas es de 61, de las cuales 58 son nativas y tres introducidas y naturalizadas. Esta estadística muy probablemente cambiará conforme se realicen estudios adicionales sobre Selaginella en Brasil.

Novelties in Selaginella (Selaginellaceae - Lycopodiophyta), with emphasis on Brazilian species.

In this paper, I describe five new species of Selaginella from Brazil (Selaginella nanuzae, Selaginella neospringiana, Selaginella pellucidopunctata, Selaginella stomatoloma, and Selaginella trygonoides), compare them to morphologically similar species, and provide a preliminary conservation status assessment for each. The new species are illustrated with scanning electron photomicrographs of stem sections, leaves, and spores, when available. Also discussed in this paper are ten species, mainly from Brazil and with new distribution records, and the forthcoming resurrection of three species also occurring in Brazil. Three further non-native and presumed naturalized species are recognized in Brazil, and publication of one additional taxon is planned. Eighty-six Selaginella species are now known from Brazil and, of these, 80 are native (including 26 / 32.5%, endemic), and six are introduced. Brazil and Mexico have the second highest number of native Selaginella species in the Neotropics after Venezuela, which is estimated to have about 100. Of the newly documented species, Selaginella cabrerensis is now known to occur in French Guiana, Brazil, and Bolivia, in addition to Colombia, and Selaginella arroyoana and Selaginella chiquitana are synonymized under it. Likewise, Selaginella potaroensis is also recorded from Costa Rica and Brazil, and Selaginella seemannii from Panama and Brazil. Finally, leaf marginal stomata are reported on the newly described species and their functionality is discussed under Selaginella stomatoloma.

ResumenEn este artículo describo cinco nuevas especies de Selaginella de Brasil (Selaginella nanuzae, Selaginella neospringiana, Selaginella pellucidopunctata, Selaginella stomatoloma y Selaginella trygonoides), las cuales comparo con especies morfológicamente similares y estimo, preliminarmente, su estado de conservación. Las nuevas especies las ilustro con fotomicrografías al microscopio electrónico de barrido de secciones de los tallos, hojas y esporas (cuando están disponibles). Diez especies adicionales son discutidas en este artículo con nuevos registros, mayormente para Brasil, y la resurrección de otras tres también presentes en este país es anunciada. Tres especies introducidas y presuntamente naturalizadas adicionales son documentadas en Brasil, mientras que se anuncia la publicación próximamente de una especie nueva que también ocurre en este país. Por lo tanto, la ocurrencia de 86 especies de Selaginella en Brasil es conocida ahora, de las cuales 80 son nativas (26 de ellas o el 32.5% son endémicas) y seis son introducidas. Brasil y México tienen el segundo mayor número de especies nativas de Selaginella en el Neotrópico, después de Venezuela que se estima que posee unas 100. De las especies documentadas por primera vez, Selaginella cabrerensis se reconoce que está distribuida en Guayana Francesa, Brasil y Bolivia, además de Colombia, y se consideran formalmente como sinónimo de ésta a Selaginella arroyoana y a Selaginella chiquitana. Adicionalmente, Selaginella potaroensis es documentada en Costa Rica y Brasil, al igual que lo es Selaginella seemannii en Panamá y Brasil. Finalmente, la presencia de estomas en los márgenes de las hojas se reporta en las cinco nuevas especies descritas y su funcionalidad se discute bajo Selaginella stomatoloma.