Abstract Radulaceae is one of the most isolated lineages of leafy liverworts. This family contains three genera and between 200 and 350 extant species worldwide. Most species belong to the genus Radula, which is subdivided into five subgenera and remains taxonomically challenging. In the framework of an integrative taxonomic revision of Radulaceae in tropical America, we are paying special attention to understudied features that may be taxonomically informative, such as spores. Here, we perform the first palynological evaluation of sixteen species of Radulaceae. The spores were processed by standard palynological techniques and described using light and electron microscopy. The spores of Radulaceae are isomorphic monads, apolar in species of the genus Radula and cryptopolar in Cladoradula, usually small to medium-sized, rarely large, inaperturate, with a circular to slightly elongated outline. The spore surface is ornamented with rounded elements, here called Granulate-type ornamentation, or with elongated elements, called Echinate-type ornamentation, and shows differences in each species. The palynological data, especially spore ornamentation, can make an important contribution to Radulaceae taxonomy for separating species or groups of species. The groups found here, however, do not fully correspond to generic and infrageneric circumscriptions as supported by molecular-phylogenetic evidence. liverworts 20 35 worldwide challenging America informative Here microscopy monads Cladoradula mediumsized, mediumsized medium sized, sized medium-sized large inaperturate outline elements Granulatetype Granulate type ornamentation Echinatetype Echinate data however molecularphylogenetic molecular phylogenetic evidence 2 3

Abstract Pollen grain morphology and the characterization of additional structures related to pollen dispersion can help to understand the strategies presented by species as well as their taxonomic circumscription. This work investigates the morphology of pollen grains and orbicules of Cedrela fissilis Vell. and Cedrela odorata L., two threatened species of the genus Cedrela P. Browne (Meliaceae A. Juss.) in Brazil. Observations of pollen grains and orbicules of the species were carried out pre- and post-chemical treatment of the samples, under light and scanning electron microscopy, aiming at recognizing structures, detailing morphological characterizations and taking measurements, the last of which were submitted to statistical treatment. The results demonstrate that the pollen grains of the two species are medium in size (measuring between 25 and 50µm), radially symmetrical, isopolar, prolate-spheroidal and 4,5-colporate with subcircular to subquadrangular amb and psilate ornamentation; the orbicules also have a smooth surface and measure about 7 to 10µm. Variation was observed in the size of pollen grains, which presented high coefficient of variation and in the orbicules, as well as in the number of apertures. circumscription Vell L L. P Meliaceae A Juss. Juss Brazil pre postchemical post chemical samples microscopy measurements measuring 2 50µm, 50µm µm , 50µm) symmetrical isopolar prolatespheroidal prolate spheroidal 4,5colporate 45colporate colporate 4,5 4 5 ornamentation 10µm apertures 5colporate 45 4,

Abstract Oncophoraceae are acrocarpous mosses that predominantly grow as tufts or cushions and especially occur on rocks and soil. The recognition of Oncophoraceae as a distinct family, as well as its generic circumscription, is not consensus among authors, and the pursuit for new information to improve its characterization is incessant. The present work aims to characterize the spore morphology and ultrastructure of 19 species (eight genera) occurring in the Americas and to evaluate the relevance of palynological data to circumscribe species, contributing to support other palynological studies. Observations were performed under Light and Electron (Scanning and Transmission) Microscopes. A Cluster Analysis was performed in order to evaluate the meaning of the palynological data, especially concerning the establishment of the species circumscription. Spores are monads, small to medium sized (10.40 to 44.20 μm), radially symmetric, subcircular in amb, heteropolar or apolar; the surface is ornamented by granules, gemmae and bacula. Anisomorphic spores were observed in eight studied species and are reported herein for the first time. The Cluster Analysis shows two groups with low similarity, which primarily differ by the polarity of the spores. The circumscription of Kiaeria and Cynodontium is corroborated by palynological characterization and endorsed by Cluster Analysis.

A morfologia dos grãos de pólen de espécies de Bromeliaceae coletadas em áreas de Floresta Atlântica do sudeste do Brasil foi estudada. As seguintes espécies foram analisadas: Aechmea bambusoides L. B. Sm. & Reitz, A. nudicaulis (L.) Griseb., A. ramosa Mart. ex Schult.f., Ananas bracteatus (Lindl.) Schult.f., Billbergia distachia (Vell.) Mez, B. euphemiae E. Morren, B. horrida Regel, B. zebrina (Herb.) Lindl., Portea petropolitana (Wawra) Mez, Pitcairnia flammea Lindl., Quesnelia indecora Mez, Tillandsia polystachia (L.) L., T. stricta Sol., T. gardneri Lindl., T. geminiflora Brongn. e Vriesea grandiflora Leme. Microscopia de luz e microscopia eletrônica de varredura foram empregadas e as espécies foram agrupadas em três tipos polínicos organizados de acordo com as características das aberturas: Tipo I - grãos de pólen pantoporados, observados em P. petropolitana; Tipo II - grãos de pólen 2-porados, observados nos gêneros Ananas, Aechmea e Quesnelia e Tipo III - grãos de pólen 1-colpado observado nos gêneros Billbergia, Pitcairnia, Tillandsia e Vriesea. Os dados polínicos levaram à elaboração de uma chave de identificação. Os resultados mostraram que as espécies analisadas podem ser separadas utilizando-se, principalmente, o padrão de aberturas e ornamentação da exina, e que essas características podem auxiliar nos estudos taxonômicos da família.

Pollen grain morphology of Bromeliaceae species collected in areas of the Atlantic Rainforest of southeastern Brazil was studied. The following species were analyzed: Aechmea bambusoides L.B.Sm. & Reitz, A. nudicaulis (L.) Griseb., A. ramosa Mart. ex Schult.f., Ananas bracteatus (Lindl.) Schult.f., Billbergia distachia (Vell.) Mez, B. euphemiae E. Morren, B. horrida Regel, B. zebrina (Herb.) Lindl., Portea petropolitana (Wawra) Mez, Pitcairnia flammea Lindl., Quesnelia indecora Mez, Tillandsia polystachia (L.) L., T. stricta Sol., T. gardneri Lindl., T. geminiflora Brongn. and Vriesea grandiflora Leme. Light and scanning electron microscopy were used and the species were grouped into three pollen types, organized according to aperture characteristics: Type I - pantoporate pollen grains observed in P. petropolitana, Type II - 2-porate pollen grains, observed in the genera Ananas, Aechmea and Quesnelia, and Type III - 1-colpate pollen grains, observed in the genera Billbergia, Pitcairnia, Tillandsia and Vriesea. Pollen data led to the construction of an identification key. The results showed that the species analyzed can be distinguished using mainly aperture features and exine ornamentation, and that these characteristics may assist in taxonomic studies of the family.