Perianth development and systematics of Aristolochia

Estructura, ontogenia y vascularización de las flores e inflorescencias de Drimys granadensis (Winteraceae)

“…La condición plesiomórfica para el número de sépalos es de tres en Canellales y Piperales, (Ronse de Craene, Soltis, & Soltis, 2003); ésta se presenta en Canellaceae (Hammel & Zamora, 2005), y en Aristolochiaceae (González & Stevenson, 2000b); el cáliz dímero (eventualmente tetrámero o indeterminado) resulta ser una sinapomorfía para las Winteraceae (Marquínez, 2009). Los dos sépalos que forman la caliptra de las flores laterales de las Winteraceae se originan en posición lateral en Drimys, Pseudowintera, Takhtajania, Zygogynum s.l., o en posición medial en Tasmannia, siendo ésta una sinapomorfía para las especies de este últi-mo género (cf.…”

Nomenclatural updates of Aristolochia subgenus Pararistolochia (Aristolochiaceae)

“…Pararistolochia shows a minimum of six anthers in the Australian species and up to 24 in the African A. goldieana. Also the number of stigmatic lobes varies, in at least some species, from 6 to 12, even within a single individual (González and Stevenson 2000). An additional morphological synapomorphy is the presence of a massive exineridge formation on the pollen grain (González and Stevenson 2002), although this character has not been confirmed for all species.…”

Spatial and temporal variation in volatile composition suggests olfactory division of labor within the trap flowers of Aristolochia gigantea

“…1) (Proctor et al, 1996). Visitors to Aristolochia flowers either are detained or simply remain within the floral chamber, and are showered with pollen when the flower transitions to the male phase, after which they depart as the flower senesces (Cammerloher, 1923;Costa and Hime, 1983;Gonzalez and Stevenson, 2000). Although…”

“…Flowers of A. gigantea are zygomorphic and consist of three congenitally united sepals that form a distinctive tubeshaped perianth that expands basally into a hollow trapping chamber (utricle) (Cammerloher, 1923;Correns, 1891;Costa and Hime, 1983;Gonzalez and Stevenson, 2000). Above the utricle, a narrow floral tube leads to a constricted opening, from which extends a conspicuous laminar surface (limb) with a calico-patterned visual display resembling the appearance of rotting flesh ( Fig.…”

“…2A, B). Within the trap, six stamens are entirely adnate to a syncarpous style forming a gynostemium that is positioned above an inferior ovary (Gonzalez and Stevenson, 2000). Furthermore, the utricle contains two patches of glandular trichomes that secrete nectar on the first day of anthesis and become dark and visually conspicuous on the second day (Hipólito et al, 2012).…”