and Kyllingiella polyphylla (A.Rich.) Lye, which can have both trimerous and dorsiventrally flattened dimerous pistils within a single spikelet (Haines & Lye, 1983; Larridon et al., 2011b).
In this tribe, as it occurs in other Cyperoideae, this annular ovary primordium possibly results from a congenital fusion of three distinct carpel primordia (trigonous ovary) or two carpel primordia (dorsiventrally and laterally compressed ovary).
They are strongly flattened dorsiventrally
. The helmet-shaped epivalve narrows from just above the cingulum gradually forming a long horn with 4 apical plates.
Column forming an obtuse angle with the ovary, straight, dorsiventrally
compressed, oblongcuneate, white suffused with dark brown, ventrally shallowly sulcate and densely papillose, 6-8 mm long, 2.3-3.5 mm wide near the apex, provided at each side of the apex with a triangular-ovate, membranaceous, acute auricle; column foot obliquely adnate to the apex of the ovary, papillose, channeled, 2-2.5 mm long, ca.
However, weak monosymmetry is present in at least some palms: in Geonoma the gynoecium is pseudomonomerous (Stauffer et al., 2002; Stauffer & Endress, 2003); some other Geonomeae have a dorsiventrally flattened gynoecium and the (sterile) androecium in female flowers is monosymmetric (Stauffer & Endress, 2003).
In Xyridaceae the calyx is monosymmetric in Abolboda and Xyris, the corolla is bilabiate in Orectanthe, and the ovary is dorsiventrally compressed in Aratitiyopea (Kral, 1998).
adaxial specific proteins via miRNA regulation, or negative regulation exerted by middle domain proteins dorsiventrally
. These are the primary determinants of areas of marginal laminar growth (Eshed et al., 2001; Kerstetter et al., 2001; McConnell et al., 2001; Reinhart et al., 2002; Rhoades et al., 2002; Emery et al., 2003; Mallory et al., 2004; Pulido & Laufs, 2010; Nakata et al., 2012).
The most important variations include: a) flower sexuality: spikelets with male and female flowers may be gynandrous (with the female flower distal), androgynous (with the male flower distal) and mesogynous (with female flowers proximal and distal to the male flowers); b) shape (shortly ovate, elliptical, lanceolate, linear, ovate, etc); c) compression (laterally or dorsiventrally
compressed or more or less terete); d) rachilla internodes more or less straight, zigzag or flexuose; e) rachilla prolongation exceeding (e.g.
Within Cypereae and Cyperaceae, species with distigmatic styles and dorsiventrally
compressed nutlets are observed.
Microsporophyll lamina soft, not dorsiventrally
Pollinia erect to horizontal (rarely descending toward center of flower, e.g., Tavaresia), nearly spherical, ellipsoidal to D-shaped in outline and then strongly dorsiventrally
flattened, with hyaline insertion crest along upper or outer margin through which pollen tubes emerge.