Relaciones filogenéticas de las especies del orden Nostocales (Cyanophyta), asociadas a algas rojas de los litorales rocosos de Veracruz

The cyanoprokaryotes of the order Nostocales constitute a monophyletic, ecologically and taxonomically very diverse group, commonly associated with red algae, and at the same time, one of the least studied orders. They are characterized by presenting heterocytes (structure responsible for nitrogen f...

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Detalles Bibliográficos
Autor: Ernesto Cabrera Becerril
Tipo de recurso: tesis de maestría
Estado:Versión publicada
Fecha de publicación:2022
País:México
Institución:Universidad Autónoma Metropolitana
Repositorio:Repositorio Institucional de la UAM Iztapalapa
Idioma:español
OAI Identifier:oai:bindani.izt.uam.mx:9s1616873
Acceso en línea:https://doi.org/10.24275/uami.9s1616873
Access Level:acceso abierto
Palabra clave:info:eu-repo/classification/LEM/Red algae
info:eu-repo/classification/LEM/Algas rojas
info:eu-repo/classification/LEM/Freshwater algae
info:eu-repo/classification/LEM/Algas de agua dulce
info:eu-repo/classification/cti/2
Descripción
Sumario:The cyanoprokaryotes of the order Nostocales constitute a monophyletic, ecologically and taxonomically very diverse group, commonly associated with red algae, and at the same time, one of the least studied orders. They are characterized by presenting heterocytes (structure responsible for nitrogen fixation) and akinetes (resistance structures). Both rhodophyta and cyanoprokaryota groups, in addition to sharing environments, also share various structural elements and levels of organization. The state of Veracruz, in addition to being highly diverse in these groups and easy to collect, is one of the most visited by students, teachers and researchers. In Mexico, the study of nostocal cyanoprokaryotes has been overlooked, taking into account that only 10 studies address them and only 3 do so specifically. Additionally, the lack of diagnostic characters for Mexican populations is added, since morphological identification has traditionally been carried out with European works. Given the above, our objectives were: to contribute to the knowledge of the specific richness of the order for the state and to carry out detailed morphological descriptions of the Nostocales species of coastal environments in Veracruz associated with red algae. For this, a collection was made during the year 2020, of cyanobacterial growths on the rocky coastline, which were preserved in silica and blotting paper to later be rehydrated with sterile seawater, to prepare cultures and semi-permanent preparations. Microphotographs of the morphological characters and their measurements were taken. The descriptions obtained were contrasted with specialized literature. An updated floristic list of benthic marine cyanoprokaryotes of the Nostocales order is presented for the state, incorporating 32 species distributed in 13 genera and 7 families. Of the total taxa, 19 correspond to additions to the flora, of these, 11 species were identified as cf. and eight at the gender level, for not fully coinciding with the specific information in the literature. The best represented families were Rivulariaceae, followed by Scytonemataceae and Calotrichaceae; those with the least diversity were Nostocaceae, Aphanizomenonaceae and Hapalosiphonaceae and Capsosiraceae. They are reported for the first time for Mexico: Desmosiphon cf. neocaledonicus, Calothrix cf. fonticola, Calothrix cf. prolifera, Rivularia cf. nitida, Rivularia cf. litorea, Scytonematopsis cf. pilosa and S. cf. fuliginosa. Additionally, three species are reported for the first time for the state: Calothrix cf. contarenii, Kyrtuthrix huatulcensis, and Scytonema cf. crispum. The site that presented the greatest specific richness was Costa de Oro, followed by Playa Muñecos and Morro de la Mancha. Likewise, sequences with the 16S and 23S genes were amplified for 15 samples. From these results, the identification of Phylonema ansata and two species corresponding to taxa not yet described for the genera Kyrtuthrix sp. and Nunduva sp., which must be described. The results reveal that the diversity of the order Nostocales in the state of Veracruz has been underestimated and works devoted to the knowledge of the group are required. KEYWORDS: 16S, 23S, Cyanoprocaryota, Diversity, Phylogeny, Specific Richness, Taxonomy.