Eupomatia

Abstract: Over the past 25 years, discoveries of Early Cretaceous fossil flowers, often associated with pollen and sometimes with vegetative parts, have revolutionized our understanding of the morphology and diversity of early angiosperms. However, few of these fossils have been integrated into the increasingly robust phylogeny of living angiosperms based primarily on molecular data. To remedy this situation, we have used a morphological dataset for living basal angiosperms (including basal eudicots and monocots) to assess the most parsimonious positions of early angiosperm fossils on cladograms of Recent plants, using constraint trees that represent the current range of hypotheses on higher-level relationships, and concentrating on Magnoliidae (the clade including Magnoliales, Laurales, Canellales, and Piperales) and eudicots. In magnoliids, our results confirm proposed relationships of Archaeanthus (latest Albian?) to Magnoliaceae, Endressinia (late Aptian) to Magnoliales (the clade comprising Degeneria, Galbulimima, Eupomatia, and Annonaceae), and Walkeripollis pollen tetrads (late Barremian?) to Winteraceae, but they indicate that Mauldinia (early Cenomanian) was sister to both Lauraceae and Hernandiaceae rather than to Lauraceae alone. Among middle Albian to early Cenomanian eudicots, we confirm relationships of Nelumbites to Nelumbo, platanoid inflorescences and Sapindopsis to Platanaceae, and Spanomera to Buxaceae. With the possible exception of Archaeanthus, these fossils are apparently not crown group members of living families but rather stem relatives of one or more families.

Abstract: A fossil angiosperm from the Brazilian Crato Formation, Endressinia brasiliana n. gen. n. sp., is described. The fossil consists of a branching axis with attached simple, narrowly ovate leaves and several terminal small flowers. One of these multiparted flowering structures is well preserved and seems close to anthesis. Tepals, staminodes, and apocarpous follicles show cellular details, such as ethereal cells. Broad staminodes bear lateral knobs that are interpreted as glands. The gynoecium consists of ca. 20 free apocarpous carpels. Among recent Magnoliales, several families share with Endressinia the floral feature of having staminodes. Only Himantandraceae and Eupomatiaceae share the character of having staminodes with glands, which are broad in Eupomatia. Thus, Endressinia might be sister to Eupomatiaceae; however, it also might represent an extinct lineage with convergent staminode morphology.

Abstract: Eupomatia (Magnoliales, Eupomatiaceae) has flowers that bear a calyptra, an unusual organ that encloses the floral bud. The structural homology and evolutionary derivation of the calyptra are unknown, although some have proposed that it is a bract, while others favor a derivation from the perianth. To address the evolutionary origin of the calyptra, we isolated, sequenced, and characterized the expression of A‐, B‐, and E‐class MADS‐box homologues from Eupomatia bennettii and a close relative, Magnolia grandiflora (Magnoliaceae). The expression patterns of organ identity genes in floral organs of Eupomatia and Magnolia were very similar. However, the expression patterns of these MADS‐box genes indicated that the ABC model is not strictly applicable to either Eupomatia or Magnolia. For example, A‐class homologues were expressed in carpels and leaves of both Eupomatia and Magnolia. In the calyptra, expression levels of B‐ and E‐class homologues were low and almost identical to those observed in leaf tissue....

Abstract: A further extraction of the bark of Eupomatia laurina R.Br. has yielded 16 substances: liriodenine (as before), norushinsunine, three new bases, benzoic acid, sitosterol, eupodienone-1 (previously EL2; but not EL3 which is an artefact from EL2), eupomatene (ELl), and seven related substances. The last eight substances, which are closely related, ere named ?eupomatenoids?. The structures of the eupomatenoids -2 to -8 have been established. Like eupomatenoid-1 (eupomatene), they are derivatives of 3-methyl-2-phenyl-5-(E)-propenylbenzofuran and are classified as lignans.