Ovules and Seeds of Trigoniaceae

Abstract

Trigonia cipoensis has a trizonate ovule primordium. The mature ovule is anatropous, bitegmic and tenuinucellate. Both integuments are of dermal origin; the inner integument is strongly multiplicative, especially after fertilisation. The mature seed is densely covered by cottony testal hairs. Of the inner integument the outer layer develops into a lignified, fibrous exotegmen, whereas the inner layer is tanniniferous. Endosperm formation is initially nuclear, the tissue later becoming cellular throughout. Ovule and seed structure indicates a relationship with the Linales and not with the Polygalales with which the family Trigoniaceae is ususally associated.

Comparative floral structure and systematics in Chrysobalanaceae s.l. (Chrysobalanaceae, Dichapetalaceae, Euphroniaceae, Trigoniaceae; Malpighiales)

“…The gynoecium is always trimerous in Euphroniaceae (this study; Warming, 1875; Petersen, 1897; Lleras, 1976; Marcano‐Berti, 1989) and mostly in Trigoniaceae (Warming, 1875; Chodat, 1895; Petersen, 1897; Lleras, 1978; Boesewinkel, 1987) (rarely four: in Ta. rotundifolia ; Lleras, 1978).…”

“…mombuttense , Boesewinkel & Bouman, 1980; Trigoniaceae , van Tieghem, 1901; Ta. cipoensis , Boesewinkel, 1987; Trigoniastrum and probably also Ta. rugosa , this study), but apparently weakly crassinucellar in Ta.…”

“…parviflora , Mauritzon, 1936; ten ovules in Ta. cipoensis , Boesewinkel, 1987), and one to two ovules in Trigoniastrum and Humbertiodendron (Léandri, 1949; Lleras, 1978; Boesewinkel, 1987) (Figs 157–160).…”

“…173). By maturity of the embryo sac, the nucellus has completely been reabsorbed and has disappeared ( Chrysobalanaceae , Tobe & Raven, 1984; Dichapetalaceae , van Tieghem, 1903; Schnarf, 1931; Boesewinkel & Bouman, 1980; Trigoniaceae , Mauritzon, 1936; Boesewinkel, 1987). In addition, in Di.…”

“…hypoleucum , this study; Ta. cipoensis , Boesewinkel, 1987). However, in Dichapetalaceae , the entire inner integument is cytoplasm‐rich in comparison with the outer integument ( Di.…”