The taxonomic significance of seed morphology in the Passiflora subgenus Astrophea (Passifloraceae)

Abstract

Th e center of diversity for Passifl ora subg. Astrophea is in low altitude areas of northern South America. Th e majority of species of this group are diffi cult to fi nd in nature. Seed morphology was described in detail for 25 species of Passifl ora subgenus Astrophea, a subgenus that until now did not exist. For morphological analysis, 20 seeds per species were measured for length, width and thickness, and the arithmetic means calculated. Th e seeds varied in length, width and thickness. Eight types of ornamentation were found. Th e margins varied among crestate, dentate, parted, entire and parted-crestate. Th e seed apex can be distinguished by the shape and position of the apical appendage. Seed shape varied among obovate, lanceolate, cordiform, and oblong to elliptical. An identifi cation key was developed and a PCA was performed both using the principal morphological characters. Morphological characters of seeds are a new source of data for delimiting taxa with quite confl icting morphological boundaries, such as seen here with the Passifl ora subgenus Astrophea. Furthermore, seed morphology is especially useful for the identifi cation of specimens with only fruits and, consequently, seeds available.

Seed morphology: An addition to the taxonomy of Astragaleae and Trifolieae (Leguminosae: Papilionoidae) from Pakistan

“…Seed size was reported to be directly related to the number of nutritional reserves that can be allocated to initial seedling development (Veloso et al, 2017). A similar report was given by Mezzonato‐Pires, Mendonç, Milward‐De‐Azevedo, and Gonçalves‐Esteves (2017) documenting that the size particularly the surface of seeds are often useful features for taxonomy. Various authors have emphasized the taxonomic relevance of the morphology and anatomy of the seeds of legumes.…”

Passifloraceae seeds from the late Eocene of Colombia

“…5; Appendix S2). Passifloroideae has compressed seeds that are larger than seeds of the other subfamilies, ranging from approximately 1.4 to 14 mm long, with ovoid, obovoid or elliptic shape and foveolate, coarsely foveolate, reticulate‐foveolate, or transversally grooved hard seed coats (e.g., de Wilde, 1972, 1974, 1976; Feuillet and MacDougal, 2007; Pérez‐Cortéz et al, 2002, 2009; Pérez‐Cortéz, 2007; Mezzonato‐Pires et al, 2017; Figs. 4 and 5).…”

Morfología y optimización de prueba de viabilidad en semillas de Passiflora spp. de Costa Rica

“…Los marcadores morfológicos, que son características que se pueden distinguir a nivel visual, pueden ser utilizados como herramienta para la caracterización (Sattar Khan et al, 2015). En Passiflora las características morfológicas de las semillas han demostrado ser útiles para la clasificación taxonómica de sus especies (Fachi et al, 2019;Mezzonato-Pires et al, 2017;Torres et al, 2019).…”