Cuscuta (dodders) is a group of parasitic plants with tremendous economic and ecological significance. Their seeds are often described as "simple" or "unspecialized" because they do not exhibit any classical dispersal syndrome traits. Previous studies of seed morphology and/or anatomy were conducted on relatively few species. We expanded research to 101 species; reconstructed ancestral character states; investigated correlations among seed characters and explored allometric relationships with breeding systems, the size of geographical distribution of species in North America, as well as the survival of seedlings. Seed morphological and anatomical characters permit the separation of subgenera, but not of sections. Identification of Cuscuta species using seed characteristics is difficult but not impossible if their geographical origin is known. Seeds of subg. Monogynella species, exhibit the likely ancestral epidermis type consisting of elongated and interlocked cells, which are morphologically invariant, uninfluenced by dryness/wetness. Subgenera Cuscuta, Pachystigma and Grammica have evolved a seed epidermis with isodiametric cells that can alternate their morphology between two states: pitted when seeds are dry, and papillose after seed imbibition. A seed coat with double palisade architecture throughout the entire seed has also apparently evolved in subgenera Cuscuta, Pachystigma and Grammica, but several species in two clades of the latter subgenus reverted to a single palisade layer outside the hilum area. The same latter species also evolved a peculiar, globose embryo, likely having a storage role, in contrast to the ancestral filiform and coiled embryo present throughout the remainder of the genus. Autogamous species had on average the highest number of seeds per capsule, whereas fully xenogamous taxa had the lowest. No correlation was revealed between the size of the seeds and the size of their geographical distribution in North America, but seedlings of species with larger seeds survived significantly longer than seedlings resulted from smaller seeds. Diversity and evolution of seed traits was discussed in relationship with their putative roles in dormancy, germination and dispersal.

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A new species, Echeveria marianae (Crassulaceae) is described from Sierra del Tigre, Valle de Juárez, State of Jalisco, Mexico. The species belongs to ser. Gibbiflorae due to of its acaulescent or short caulescent rosette habit, paniculiform inflorescence, conical-urceolate corolla, and tricolpate pollen grains. Within ser. Gibbiflorae it shares morphological affinities with E. novogaliciana and E. dactylifera from which it differs in the shape, color and margin of leaves, corolla size and color, stamen length, nectaries morphology, and its geographical distribution. ResumenSe describe Echeveria marianae (Crassulaceae) como una especie nueva para la ciencia de la Sierra del Tigre, Valle de Juárez, Estado de Jalisco, México. Esta especie pertenece a la ser. Gibbiflorae por poseer un breve tallo o acaule, arrosetada, inflorescencia paniculiforme, corola cilíndrico-urceolada y granos de polen tricolpado. Dentro de las especies de esta ser. Gibbiflorae, comparte afinidades morfológicas con E. novogaliciana y E. dactylifera, de las cuales difiere en la forma, color y margen de las hojas, color y tamaño de la corola, longitud de los estambres, morfología de los nectarios y su distribución geográfica.

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Eryngium es uno de los géneros más extensos y con mayores dificultades taxonómicas entre las Apiaceae. El grupo incluye de 230 a 250 especies distribuidas en las regiones templadas y tropicales del planeta. Para México se han registrado alrededor de 60 especies, 21 de ellas existen en el estado de Michoacán. Éstas se distribuyen en cinco tipos de vegetación, pero principalmente lo hacen en el pastizal, en bosques de pino-encino y de coníferas. Se incluye una clave para la determinación de las especies citadas.

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El estudio florístico realizado en el área de la comunidad indígena de Nuevo San Juan Parangaricutiro registró la presencia de 108 familias, con 307 géneros, 716 especies y 16 taxa infraespecíficos, de los cuales, 52 son helechos y afines, 16 gimnospermas, 120 monocotiledóneas y 544 dicotiledóneas. Las familias mejor representadas son: Compositae (135), Leguminosae (58), Gramineae (57), Labiatae (26), Solanaceae (21) Orchidaceae (20) y Polypodiaceae (18). 60.7% de las especies corresponden a la forma de vida herbácea (perenne y anual), 19.1% son arbustos, 10.0% árboles, 4.2% trepadoras, 3.3% epífitas, 1.8% parásitas, “saprófitas” 0.5% y acuáticas 0.4%.

The genus Vaccinium contains about 400 species distributed worldwide, but only a few species and varieties have had their phenolic composition and biological activity documented. In this study, phenols, flavonoids, anthocyanins, antioxidant and antimicrobial activity of methanolic extracts of Vaccinium stenophyllum Steud. fruits: 1-totally immature, 2-immature, 3-immature/close to maturity and 4-mature, were determined using UV-Visible spectrometry and HPTLC. The totally immature fruit extract showed the highest content of total phenols (19.153 ± 0.175 mg GAE/g DW), chlorogenic acid (20.867 ± 0.240 mg CAE/g DW), and the highest antioxidant activity by ABTS●+ (196.761 ± 0.641 µM TE/g DW) and DPPH● (146.580 ± 6.466 µM TE/g DW). Immature, immature/close to maturity and mature fruits extracts, exhibited the lowest MIC (9.37 mg/mL) and MBC (18.75 mg/mL) against Escherichia coli, Salmonella choleraesuis, and Shigella flexneri. The mature fruits extract exhibited the highest content of total anthocyanins (0.141 ± 0.004 mg CE/g DW) and cyanidin-3-glucoside (19.230 ± 0.309 mg CGE/g DW). The content of phenols, flavonoids and anthocyanins was higher than that reported for other Vaccinium species. These results showed the relevance of Vaccinium stenophyllum Steud. for breeding purposes to enhance the bioactivity of cultivars, or as a source of natural additives for the food industry, among others.