1985/11/01 by Rolf Dahlgren, An‐Ming Lu · 2 citations
Agricultural and Biological Sciences · #Plant Diversity and Evolution #Plant and animal studies #Fern and Epiphyte Biology #Ovule #Megaspore #Biology #Endosperm #Botany #Microspore #Integument #Tapetum #Locule #Epidermis (zoology) #Anatomy #Pollen #Stamen
paper · doi:10.1111/j.1756-1051.1985.tb01660.x
openalex publication_date 1985/11/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/06/11
Campynemanthe Baill. consists of three species endemic to New Caledonia. Two species are studied and compared. The tapetum is secretory with 2‐nucleate tapetal cells. Microsprogenesis is successive, microspore tetrads are isobilateral and the pollen grains are free and inaperturate or have a weakly defined aperture. Placentation is axile with 3–4 ovules in each of the three locules. Ovules are anatropous and crassinucellate with the micropyle formed by the inner integument alone. The archesporial cell cuts off a parietal cell, which divides to form a parietal tissue. The nucellar epidermis divides periclinally at the nucellar apex to become 2‐layered. The megaspore tetrad is T‐shaped, in which the micropylar megaspore cells are separated by an oblique wall. The chalazal megaspore enlarges and apparently developes into a Polygonum‐type embryo sac, but a mature embryo sac has not been seen. The ripe seeds are pale and non‐phytomelaniferous. They have copious endosperm rich in fatty oils. The embryo is minute. These characters and gross morphological similarities support relationship with Campynema Labill., but there are also conspicuous differences. The two genera are considered related. They also closely approach genera of the variable family Melanthiaceae and there are reasons to include them in this family.