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2. The genus Eutreptiella (Euglenophyceae/Euglenozoa) across its global distribution range.

Author

Hernández Márquez, Sinuhé, Zamudio‐Resendiz, María Eugenia, Murrieta‐Alarcón, Montserrat, Núñez Resendiz, María Luisa, Dreckmann, Kurt M., and Sentíes, Abel

Subjects
MARINE ecosystem health, BIOTECHNOLOGY, GENETIC variation, MARINE ecology, PHENOTYPIC plasticity
Abstract

The genus Eutreptiella (Euglenophyceae/Euglenozoa) comprises unicellular organisms known for their photosynthetic capacity and significant role in marine ecosystems. This review highlights the taxonomic, ecological, and biotechnological characteristics of Eutreptiella species, emphasizing their morphological and genomic adaptations. Eutreptiella species exhibit high phenotypic plasticity, enabling adaptation to various environmental conditions, from nutrient‐rich waters to high‐salinity conditions. They play a crucial role in primary production and nutrient cycling in marine ecosystems. Genetic and transcriptomic studies have revealed their complex regulatory mechanisms and potential for biofuel and nutraceutical production. Eutreptiella blooms significantly impact local ecosystems, influencing nutrient availability and community dynamics. Additionally, interactions with associated bacteria enhance their growth and metabolic capabilities. The genus shows substantial genetic variability, suggesting potential misidentifications or a polyphyletic nature. Further comprehensive studies are needed to clarify their taxonomy and evolutionary relationships. Understanding and managing Eutreptiella populations is essential to leverage their biotechnological potential and ensure the health of marine ecosystems. [ABSTRACT FROM AUTHOR]

Published
2024
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5. Diversidad de dinoflagelados atecados del orden Gymnodiniales (Dinophyceae), con énfasis en aquellos formadores de florecimientos algales nocivos en las costas del Pacífico Mexicano

Author

Escárcega Bata, Alexis de Jesús, Núñez Reséndiz, María Luisa, Ruiz de la Torre, Mary Carmen, Dreckmann, Kurt M., Zamudio Resendiz, Ma. Eugenia, Sentíes, Abel, Escárcega Bata, Alexis de Jesús, Núñez Reséndiz, María Luisa, Ruiz de la Torre, Mary Carmen, Dreckmann, Kurt M., Zamudio Resendiz, Ma. Eugenia, and Sentíes, Abel

Abstract

Background and Aims: The order Gymnodiniales is composed of 11 families, 63 genera and 641 taxonomically valid species. These dinoflagellates are characterized by having a very fragile cell wall. In addition, some species can produce phycotoxins and form dense blooms. In the case of the Mexican Pacific coast, studies focused on knowing the diversity of this group are still limited, despite the economic, social, and ecological importance of these microorganisms. Therefore, the objective of this study was to make a floristic list from a bibliographical review, integrating only the records supported by micrographs, to know the diversity of athecate dinoflagellates of the order Gymnodiniales present in the Mexican Pacific Ocean, with emphasis on those that form harmful algal blooms.Methods: The search for information was carried out in publications (articles and book chapters), from the first record (1943) to the present (November 2022). Each record was confirmed only by the existence of optical and scanning electron micrographs.Key results: The Mexican Pacific is made up of 11 coastal states, where the presence of 10 families, 31 genera and 103 species (which represents 16% of the total number of species recorded worldwide) is currently reported for the order Gymnodiniales. Of the 11 families that make up this order, the Gymnodiniaceae family grouped 29% of the total number of species recorded for the Mexican Pacific, where the genera Gymnodinium and Gyrodinium presented the largest number of species.Conclusions: The evidence presented in this study showed that there is a low diversity for this order in the Mexican Pacific, so it is necessary to implement a greater sampling effort, in addition to venturing into different molecular tools that allow obtaining a better approximation of the diversity in the Mexican coasts., Antecedentes y Objetivos: El orden Gymnodiniales está compuesto por 11 familias, 63 géneros y 641 especies taxonómicamente válidas. Estos dinoflagelados se caracterizan por presentar una pared celular muy frágil. Además, algunas especies pueden llegar a producir potentes toxinas e incluso tienen la capacidad para formar grandes florecimientos. Los estudios enfocados en conocer la diversidad de este grupo, en el caso de las costas del Pacífico Mexicano, siguen siendo limitados, a pesar de la importancia económica, social y ecológica de estos microorganismos. Por lo tanto, el objetivo de este estudio fue realizar un listado florístico a partir de una revisión bibliográfica, que integre únicamente a los registros respaldados por micrografías, para conocer la diversidad de dinoflagelados atecados del orden Gymnodiniales presentes en el Pacífico Mexicano, con énfasis en aquellos formadores de florecimientos algales nocivos.Métodos: La búsqueda de información se realizó en publicaciones (artículos y capítulos de libros), desde el primer registro (1943) hasta la actualidad (noviembre 2022). Cada registro fue confirmado únicamente mediante la existencia de micrografías ópticas y de electrónicas de barrido.Resultados clave: El Pacífico Mexicano está conformado por 11 estados costeros, donde actualmente se tiene reportada la presencia de 10 familias, 31 géneros y 103 especies (16% del total de las registradas a nivel mundial) para el orden Gymnodiniales. De las 11 familias que conforman a este orden, la familia Gymnodiniaceae agrupó 29% del total de especies registradas para el Pacífico Mexicano, donde los géneros Gymnodinium y Gyrodinium presentaron el mayor número de especies.Conclusiones: La evidencia presentada en este estudio demostró que existe una baja diversidad para este orden en el Pacífico Mexicano, por lo que es necesario implementar un mayor esfuerzo de muestreo, además de incursionar en diferentes herramientas moleculares que permitan obtener una mejor aproximac

Published
2023

20. Análisis morfométrico de las especies simpátricas del complejo Crassiphycus corneus/C. usneoides (Gracilariaceae, Rhodophyta) en las costas mexicanas del Golfo de México y Mar Caribe

Author

Vilchis, Martha Isabel, Dreckmann, Kurt M., Quintanar Isaías, Alejandra, Sentíes, Abel, Vilchis, Martha Isabel, Dreckmann, Kurt M., Quintanar Isaías, Alejandra, and Sentíes, Abel

Abstract

Background and Aims: Crassiphycus corneus and C. usneoides form a morphological complex of macroalgal species due to the overlap in the characters that delimit them. Given their low phenotypic plasticity and sympatric distribution, discrimination between both species is complicated. Therefore, the aim of this study was to morphometrically evaluate some anatomical characters that allow discrimination of species within the complex. Methods: With the 24 quantitative measurements obtained from 40 specimens of Crassiphycus corneus and C. usneoides, a principal component analysis was performed to determine whether there was morphometric discrimination between the species. The result of this analysis was evaluated by a NP-MANOVA. The arithmetic means and confidence intervals of the characters with the greatest weight in discrimination were represented in a graphic. In addition, a cluster analysis was performed to better support the previous analysis. Key results: The principal components analysis showed 24 components, of which the first three explain 88.6% of the variance. This analysis and the NP-MANOVA showed that the characters that differentiate both species are the largest diameter of the thallus in the medium portion and the largest and smallest diameter of the thallus in the apical portion, which, according to the arithmetic mean, are significantly larger in Crassiphycus usneoides compared to C. corneus. Cluster analysis based on the Euclidean distance and the UPGMA algorithm strengthened the previous analyses, confirming the presence of two groups (C. corneus and C. usneoides). Conclusions: The performed morphometric analysis proved efficient for the segregation of the species of the complex, and may serve as a reference point for the taxonomic delimitation of other cryptic macroalgal species., Antecedentes y Objetivos: Crassiphycus corneus y C. usneoides forman un complejo morfológico de especies de macroalgas, debido a la sobreposiciónen los caracteres que las delimitan. Dada su baja plasticidad fenotípica y distribución simpátrica, la discriminación entre ambas especies resultacomplicada. Por lo tanto, el objetivo del presente trabajo fue evaluar morfométricamente algunos caracteres anatómicos que permitan la discriminaciónde las especies del complejo.Métodos: A partir de 24 medidas cuantitativas obtenidas de 40 ejemplares de Crassiphycus corneus y C. usneoides, se realizó un análisis de componentesprincipales para determinar si existía discriminación morfométrica entre las especies. El resultado de este análisis fue evaluado mediante unNP-MANOVA. La media aritmética y los intervalos de confianza de los caracteres con mayor peso en la discriminación fueron graficados. Complementariamente,se realizó un análisis de agrupamiento para dar mejor sustento a los análisis anteriores.Resultados clave: El análisis de componentes principales arrojó 24 componentes, de los cuales los primeros tres explican 88.6% de la varianza. Dichoanálisis y el NP-MANOVA mostraron que los caracteres que diferencian a ambas especies son el diámetro mayor del talo en la porción media y eldiámetro mayor y menor del talo en la porción apical, los cuales, según la media aritmética, son significativamente más grandes en Crassiphycususneoides que en C. corneus. El análisis de agrupamiento, basado en el índice de disimilitud de distancia euclidiana y el algoritmo UPGMA, robusteciólos análisis anteriores, confirmando la presencia de dos grupos (C. corneus y C. usneoides).Conclusiones: El análisis morfométrico realizado demostró ser eficiente para la segregación de las especies del complejo, y podrá servir como puntode referencia para la delimitación taxonómica de otras especies crípticas de macroalgas.Palabras clave: análisis de agrupamiento, componentes principales, discriminación, especi

Published
2020

26. Meristotheca spinella Nunez-Resendiz, Dreckmann & Senties 2019, sp. nov

Author

Núñez-Resendiz, María Luisa, Dreckmann, Kurt M., Sentíes, Abel, and León-Tejera, Hilda P.

Subjects
Meristotheca, Florideophyceae, Gigartinales, Rhodophyta, Biodiversity, Meristotheca spinella, Plantae, Solieriaceae, Taxonomy
Abstract

Meristotheca spinella Núñez-Resendiz, Dreckmann & Sentíes, sp. nov. (Figs 2, 3) HOLOTYPE. — UAMIZ-1332 (Fig. 2A), tetrasporophyte, collected at Bahia Tortuga (19.2135°N, 90.4235°W), Campeche (Mexico), on 06.VI.2015, collected by M. L. Núñez & K. M. Dreckmann. GenBank accession number MK135825. ISOTYPE. — UAMIZ-1331, tetrasporophyte, collected at Bahia Tortuga, Campeche (Mexico), on 06. VI.2015, collected by M. L. Núñez & K. M. Dreckmann. GenBank accession number MK 135823. PARATYPES. — Listed in Table 1. ETYMOLOGY. — The specific epithet spinella refers to the numerous short branches or spine-shaped proliferations that completely cover the margins of the main axes and branches. DIAGNOSIS. — Thalli 20−35 cm high, terete, dark red in color, attached by a discoid holdfast, branching dichotomously, alternately, opposite or laterally, primary axes 1250-1500 µm in diameter; branches 550-750 µm in diameter, covered with small spine-shaped branchlets. Narrow medullary filaments with numerous single-celled rhizoids, 2.5-4 µm in diameter. Inner cortex with five to six layers of cells, 25-45 µm × 20−30 µm in diameter, with small connective filaments. Outer cortex with four to five layers of cells, 10-45 µm long and 4-14 µm in diameter. Tetrasporangia claviform, 20-30 µm long and 4-7 µm in diameter, basally anchored by an elongated supporting cell that can form 3-celled cortical filaments, 7-10 µm long and 4-6 µm in diameter. Cystocarps ellipsoidal, 600-650 µm long and 320-430 µm in width. ECOLOGY. — Populations of Meristotheca spinella Núñez-Resendiz, Dreckmann & Sentíes, sp. nov. were found throughout the year, with greater abundance during the spring (tetrasporophytic state) and summer (vegetative state). They were growing in sandy environments of turbid waters, with little exposure to light, attached to rocky substrata (1-1.5 m deep). They were part of the algal canopy of the submerged algal community together with different species of large red algae, such as Alsidium seaforthii (Turner) J.Agardh, Crassiphycus corneus (J.Agardh) Gurgel, J.N.Norris & Fredericq, C. usneoides (C.Agardh) Gurgel, J.N.Norris & Fredericq, Eucheumatopsis isiformis, Meristotheca cylindrica, and Tepoztequiella rhizoidea, which were as abundant as M. spinella Núñez-Resendiz, Dreckmann & Sentíes, sp. nov. It was also a conspicuous component of the algal drift at the end of summer., Published as part of Núñez-Resendiz, María Luisa, Dreckmann, Kurt M., Sentíes, Abel & León-Tejera, Hilda P., 2019, Meristotheca spinella Núñez-Resendiz, Dreckmann & Sentíes, sp. nov. (Solieriaceae, Rhodophyta) a new cylindrical species from the southwestern Gulf of Mexico, pp. 63-72 in Cryptogamie, Algologie 20 (6) on pages 65-67, DOI: 10.5252/cryptogamie-algologie2019v40a6, http://zenodo.org/record/7819016

Published
2019
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32. Codiophyllum mexicanum sp. nov. (Halymeniaceae, Rhodophyta), first record of a stalked red alga associated with sponges in the western Atlantic.

Author

Núñez Resendiz, María Luisa, Dreckmann, Kurt M., Wynne, Michael J., and Sentíes, Abel

Subjects
*RED algae, *CERAMIALES, *RECORDS, *OCEAN, *THALLUS, *SPECIES
Abstract

The species of the family Halymeniaceae are characterised by their multiaxial thallus and sexual reproduction, involving carpogonial branches and auxiliary cells borne in filamentous ampullae and tetrasporangia decussately or cruciately divided. Most species of the genera Thamnoclonium, Spongophloea, Codiophyllum and Carpopeltis belong to the group of red algae associated with sponges that, so far, have been recorded only in the Indian and Pacific Oceans. In a survey along the Campeche coast of Mexico, however, we found numerous specimens of a stalked red alga associated with a sponge. On the basis of molecular rbcL sequences and morphological features, these specimens proved to be a species of Codiophyllum. Given its independent phylogenetic position within the genus, morphological differences with C. flabelliforme and C. natalense (the other two known species), such as almost cylindrical, non-extended or flabellate axes, the lateral branching pattern, flattened specialised proliferations, and its geographic distribution, we described it as the new species C. mexicanum, the first stalked red alga associated with sponges described and recorded for the western Atlantic. [ABSTRACT FROM AUTHOR]

Published
2020
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37. Macroalgas bentónicas de la laguna de Tampamachoco, Veracruz, México

Author

Dreckmann, Kurt M and Pérez-Hemández, Marco A

Abstract

A total of 23 macroalgal species were identified in Laguna Tampamachoco, Veracruz, Mexico: 9 ChIorophyceae, 2 Phaeophyceae and 12 Rhodophyceae. Algal richness per area is relatively higher (60-100 times) than in another coastal lagoon and one estuary of the area (Laguna Madre and Tamiahua with 29 and 22 species respectively). We report the presence of Phaeophyceae in this environment for the first time. The three sites have 58 species in total, twice the number reported from any other North Atlantic estuarine region. A total of 23 macroalgal species were identified in Laguna Tampamachoco, Veracruz, Mexico: 9 ChIorophyceae, 2 Phaeophyceae and 12 Rhodophyceae. Algal richness per area is relatively higher (60-100 times) than in another coastal lagoon and one estuary of the area (Laguna Madre and Tamiahua with 29 and 22 species respectively). We report the presence of Phaeophyceae in this environment for the first time. The three sites have 58 species in total, twice the number reported from any other North Atlantic estuarine region.

Published
2016

38. El alga Digenea simplex (Ceramiales: Rhodomelaceae) en México: variación biogeográfica

Author

Dreckmann, Kurt M and Sentíes G., Abel

Abstract

The alga Digenea simplex (Wulfen) C. Agardh has been reported in forty seven Mexican localities. A detailed description of reproductive and morphological features is given hete for the first time. Its presence in Bahía Banderas, Nayarit (Pacific of Mexico) is a first record. The lack of sexual structures suggests that Mexican populations are monophasic. The only morphological difference observed in distant populations (Nayarit, Tamaulipas and Quintana Roo) is lhe size of individual plants (not statistically significant). There ís not enought evidence to support taxonomic seggregates. The alga Digenea simplex (Wulfen) C. Agardh has been reported in forty seven Mexican localities. A detailed description of reproductive and morphological features is given hete for the first time. Its presence in Bahía Banderas, Nayarit (Pacific of Mexico) is a first record. The lack of sexual structures suggests that Mexican populations are monophasic. The only morphological difference observed in distant populations (Nayarit, Tamaulipas and Quintana Roo) is the size of individual plants (not statistically significant). There ís not enought evidence to support taxonomic seggregates.

Published
2016

43. Gracilaria microcarpa sp. nov. (Gracilariaceae, Rhodophyta) from the southwestern Gulf of Mexico.

Author

Dreckmann, Kurt M., Resendiz, María Luisa Núñez, and Sentíes, Abel

Subjects
*GRACILARIACEAE, *RED algae, *CLASSIFICATION of algae, *SPECIES diversity, *BIODIVERSITY, *ALGAE
Abstract

Although the genus Gracilaria is well represented on the Mexican coasts, there are few studies focused on the taxonomic aspects and the clarification of the relationships between species. The high morphological plasticity exhibited by several of its representatives could underestimate the true species richness. In the present study, a group of cylindrical specimens of Gracilaria from the southeastern Gulf of Mexico, previously identified as G. cornea, was collected. Based on COI-5P and rbcL sequences, these samples formed an independent group closely related to G. ferox, a flat species. Morphologically, our specimens differed from G. ferox and the other species of Gracilaria by the presence of very small cystocarps and a thick pericarp composed of many layers of cells. We propose Gracilaria microcarpa sp. nov. as the name for this group of cylindrical specimens from the Yucatan Peninsula of Mexico. [ABSTRACT FROM AUTHOR]

Published
2018
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44. Tepoztequiella rhizoidea gen. et sp. nov. (Solieriaceae, Rhodophyta) from the Yucatan Peninsula, Mexico.

Author

NÚÑEZ RESENDIZ, MARÍA LUISA, DRECKMANN, KURT M., SENTÍES, ABEL, ZUCCARELLO, GIUSEPPE C., and LEÓN-TEJERA, HILDA P.

Subjects
*RED algae, *BIODIVERSITY, *ALGAE, *PHYLOGENY, *SOLIERIACEAE, *CARRAGEENANS
Abstract

Molecular methods have greatly aided in discovering new diversity in many cryptic algal groups. Molecularassisted species discovery has focused morphological analyses on previously overlooked taxa, leading to a better understanding of diversity and evolutionary patterns. The Yucatan Peninsula, as a junction of North and South American Atlantic floras, is very diverse and, while a well-explored area, continues to reveal new species. Our studies in this area have revealed a new cylindrical member of the Solieriaceae. Based on COI-5P, rbcL and RuBisCo spacer sequences, we show that this entity is phylogenetically unique. Its position in phylogenetic analyses, combined with morphological characters and the genetic divergence from other species and genera within the family, strongly supports the establishment of Tepoztequiella rhizoidea gen. & sp. nov. The diagnostic character of T. rhizoidea is the presence of many rhizoids arising from medullary filaments and from the cells of the inner cortex. [ABSTRACT FROM AUTHOR]

Published
2018
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46. Phylogeography of Hydropuntia cornea/ Hydropuntia usneoides complex (Gracilariales, Rhodophyta) in the Yucatan Peninsula.

Author

Núñez-Resendiz, María Luisa, Zuccarello, Giuseppe C., Dreckmann, Kurt M., and Sentíes, Abel

Subjects
PHYLOGEOGRAPHY, EVOLUTIONARY theories, RED algae, PHENOTYPIC plasticity, HUMAN genetic variation
Abstract

Phylogeographic studies can contribute to our understanding of the evolutionary forces acting on the patterns of genetic variation and the evolutionary history of species. The Hydropuntia cornea/ Hydropuntia usneoides species complex consists of two common species of red algae in the Gulf of Mexico and Caribbean Sea. Both species exhibit high phenotypic plasticity and total overlap in morphological characters and are only distinguished genetically (group GI, assigned to H. usneoides and group GII, assigned to H. cornea). In the Yucatan Peninsula, where they are abundant, they have a sympatric distribution. In order to understand the historical events and their influence on the current distribution patterns of these species around the Yucatan Peninsula and compare them with some populations from Venezuela and Brazil, we analyzed variation in the plastid-encoded RuBisCo spacer. A total of 133 individuals collected from 14 sites were sequenced. The analyses revealed 12 haplotypes (R1-R12). The haplotype network revealed two major groups (GI and GII) separated by three mutational steps. Group I was found in almost all sampled sites ( n = 13), while GII was found in six sites but was absent from the Gulf of Mexico (Campeche). Haplotype R1 was the most abundant in GI, and haplotype R4 was dominant in GII. Genetic variation was higher in GI than in GII. Mismatch distribution suggests that GI may be in a period of demographic equilibrium, and GII experienced a recent demographic expansion and may have come from the south when the northern portion of the peninsula emerged (2.8 million years ago). Our results revealed that the Yucatan Peninsula is a mix of southern and northern floristic influences, which can be explained by the geological events in the area. [ABSTRACT FROM AUTHOR]

Published
2017
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49. Clorophyta (algas verdes) marinas bentónicas intermareales de Michoacán, Pacífico mexicano

Author

Marcos Bucio-Pacheco and Dreckmann, Kurt M.

Subjects
Chlorophyta marinas bentónicas, Pacífico mexicano, Biología, florística, Michoacán, Penicillus sibogae
Abstract

Veintiséis especies de Chlorophyta (algas verdes) marinas bentónicas intermareales son reportadas para 12 localidades costeras en Michoacán, Pacífico mexicano. Penicillus sibogae A. Gepp et E.S. Gepp, previamente conocida para el Océano Índico es reportado por primera vez para el Pacífico mexicano. El objetivo del presente trabajo es contribuir al conocimiento florístico del litoral michoacano.

Published
1997

50. Phylogeography of Hydropuntia cornea/Hydropuntia usneoidescomplex (Gracilariales, Rhodophyta) in the Yucatan Peninsula

Author

Núñez-Resendiz, María Luisa, Zuccarello, Giuseppe C., Dreckmann, Kurt M., and Sentíes, Abel

Abstract

Abstract:Phylogeographic studies can contribute to our understanding of the evolutionary forces acting on the patterns of genetic variation and the evolutionary history of species. The Hydropuntia cornea/Hydropuntia usneoidesspecies complex consists of two common species of red algae in the Gulf of Mexico and Caribbean Sea. Both species exhibit high phenotypic plasticity and total overlap in morphological characters and are only distinguished genetically (group GI, assigned to H. usneoidesand group GII, assigned to H. cornea). In the Yucatan Peninsula, where they are abundant, they have a sympatric distribution. In order to understand the historical events and their influence on the current distribution patterns of these species around the Yucatan Peninsula and compare them with some populations from Venezuela and Brazil, we analyzed variation in the plastid-encoded RuBisCo spacer. A total of 133 individuals collected from 14 sites were sequenced. The analyses revealed 12 haplotypes (R1–R12). The haplotype network revealed two major groups (GI and GII) separated by three mutational steps. Group I was found in almost all sampled sites (n= 13), while GII was found in six sites but was absent from the Gulf of Mexico (Campeche). Haplotype R1 was the most abundant in GI, and haplotype R4 was dominant in GII. Genetic variation was higher in GI than in GII. Mismatch distribution suggests that GI may be in a period of demographic equilibrium, and GII experienced a recent demographic expansion and may have come from the south when the northern portion of the peninsula emerged (2.8 million years ago). Our results revealed that the Yucatan Peninsula is a mix of southern and northern floristic influences, which can be explained by the geological events in the area.

Published
2017
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