Morfologia dos esporos das espécies de Leucobryaceae Schimp. (Bryophyta) do Parque Estadual de Ilha Grande, Município de Angra dos Reis, Estado do Rio de Janeiro

2019

Amphidium Schimp. is characterized by cushion-forming erect primary stems, linear-lanceolate leaves, and gymnostome capsules. The phylogenetic position of Amphidium is uncertain, with the genus having been variously included in Zygodontaceae Schimp., Rhabdoweisiaceae Limpr., Orthotrichaceae Arn. and Amphidiaceae M. Stech. A palynological investigation was performed of the three species of the genus that occur in the Americas: Amphidium lapponicum (Hedw.) Schimp., Amphidium mougeotii (Bruch & Schimp.) Schimp., and Amphidium tortuosum (Hornsch.) Cufod. Spores were observed and measured for greatest diameter under light microscopy both before and after acetolysis. Non-acetolyzed spores were observed under scanning electron microscopy to assess surface ornamentation of the sporoderm. All spores observed were smaller than 20 µm and heteropolar, with surface ornamentation reflecting a combination of different elements, such as gemmae, rugulae and perforations. The palynological characteristics observed here suggest that the genus Amphidium, and thus its contained species, be placed in their own family.

Section: Introductionmentioning

confidence: 99%

Palynology of Amphidium Schimp. (Amphidiaceae M. Stech): can spore morphology circumscribe the genus?

Passarella

2019

“…Spore morphology and ontogeny are important for evaluating bryophytes taxonomy and phylogeny, as evidenced by several studies (Clarke 1979;Horton 1982;Mishler & Churchill 1984;Blackmore & Barnes 1987;Brown & Lemmon 1980;1984a;b;1988;1991;Estébanez et al 1997;Luizi-Ponzo et al 1997;Caldeira et al 2006;Luizi-Ponzo & Melhem 2006a;b;Yano & Luizi-Ponzo 2006;2011;Savaroglu et al 2007;Rocha et al 2008;Savaroglu & Erkara 2008;Alfayate et al 2013;Brown et al 2015;Rodrigues & Luizi-Ponzo 2015;Savaroglu 2015;Savaroglu et al 2017;Silva-e-Costa et al 2017). Nonetheless, data are still scarce for Erpodiaceae (Erdtman 1965), or have been reported in taxonomic studies (Pursell 1966;1994;Crum 1972;Yano 1984;Yano & Santos 1993;Stone 1997;Pursell & Allen 2002;Daniels et al 2012).…”

Section: Introductionmentioning

confidence: 99%

Complex sporoderm structure in bryophyte spores: a palynological study of Erpodiaceae Broth.

Silva-e-Costa

2019

Palynological studies of bryophytes are critical for evaluating the taxonomic relevance of their spores. They also provide important support to paleoecological investigations that, usually, treat bryophytes as a whole, which does not permit the evaluation of specific functional traits of a special taxonomic unit. The present study investigated the morphology and ultrastructure of spores of five species of Erpodiaceae (Bryophyta), and assessed the implications for taxonomy and the recognition of spores of past records. Erpodiaceae includes corticolous and saxicolous plants that are widely distributed throughout tropical and temperate regions. The spores were found to be isomorphic and apolar with a subcircular amb, granulate, inaperturate. The sporoderm possesses a perine, an exine and a stratified intine. The perine is largely responsible for spore surface ornamentation. The occurrence of exine projections, in isolation or sustaining the elements of the perine, characterizes sporoderm structure with features similar to that of a semitectum, a distinctive characteristic that has not been reported previously for bryophyte spores.

“…Many studies on spores have addressed different aspects of various groups (Heckman 1970;Blackmore & Barnes 1987;Brown & Lemmon 1980;1984a;b;1988;1991;Estébanez et al 1997;Luizi-Ponzo & Barth 1998;Luizi-Ponzo & Melhem 2006;Caldeira et al 2006;Yano & Luizi-Ponzo 2006;Rocha et al 2008;Rodrigues & Luizi-Ponzo 2015;Savaroğlu 2015;Savaroğlu et al 2017;Silva-e-Costa et al 2017). However, little is known about morphology of the spores of the genus Plagiochila.…”

Section: Introductionmentioning

confidence: 99%

Spores of Plagiochila (Dumort.) Dumort.: the taxonomic relevance of morphology and ultrastructure

Silva-e-Costa

2019

Plagiochilaceae is a family of leafy liverworts that are distributed worldwide. It is of great importance due to its taxonomic and ecological implications among bryophytes. Most species of the family belong to the genus Plagiochila, but there is no consensus regarding its infrageneric circumscription. There have been few palynological studies involving Plagiochilaceae and Plagiochila. Here, we describe the spore morphology of seventeen species of Plagiochila and discuss the taxonomic value of palynological characters for these taxa. The spores were processed by standard palynological techniques and analyzed using light and electron microscopy. The spores were found to be apolar, spheroidal, released monads that vary in size from 13µm to 58µm (small to large size). The sporoderm comprises an intine (stratified), a nexine, and a sexine. The spore surface is ornamented with granules that vary in shape and morphology, thus allowing the studied species to be grouped into four spore types: regular and delicate granulate, irregular and coarse granulate, long granules with flattened apices, and long and straight granules. Hierarchical cluster analysis revealed five different groups of species, evidencing the importance of spore information for taxonomic and phylogenetic studies.