Hedyosmum-Like Fossils in the Early Cretaceous Diversification of Angiosperms

Abstract

Premise of research. Early Cretaceous Hedyosmum-like fossils are important because they provide information on the pistillate flowers and fruits of plants that produced Asteropollis pollen, which is common and widely distributed very early in the history of angiosperms. Hedyosmum (Chloranthaceae) is also the only extant genus for which there is a plausible fossil presence at such an early stage of angiosperm evolution. Methodology. The fossils were sieved out of unconsolidated sediments and cleaned with HF, HCl, and water. External morphology and internal anatomy were studied using scanning electron microscopy and synchrotron radiation X-ray tomographic microscopy. Pivotal results. New information on Hedyosmum-like fossils is provided based on pistillate flowers and fruits with adhering Asteropollis pollen from the Early Cretaceous of Portugal. The fossils are assigned to a new Early Cretaceous taxon, Hedyflora crystallifera, which in external morphology is closely similar to extant Hedyosmum. However, the fossils differ from the extant genus in having a crystalliferous endotesta with cells that have endoreticulate infillings, a feature characteristic of all extant Chloranthaceae except Hedyosmum. Extant Hedyosmum has a thin, unspecialized seed coat. This new discovery confirms earlier predictions that an endotestal seed coat is ancestral for Chloranthaceae as a whole but has been lost in the lineage leading to extant Hedyosmum. Conclusions. Hedyflora confirms the divergence of the Hedyosmum lineage from other Chloranthaceae very early in the angiosperm radiation but refutes these early fossils as evidence of extant Hedyosmum in the Early Cretaceous.

Groundless Research Published on the International Journal of Plant Sciences

“…To elucidate the situation and avoid further confusion, Friis, Crane and Pedersen have to clearly declare which of the two conflicting parties they finally take, Friis et al (2019) or Herendeen et al (2017)? The genus Hedyflora cannot be a valid botanical name except Friis et al could convincingly demonstrate the presence of the claimed ovule(s).…”

“…According to Friis et al (2019), "pendant, orthotropous, and bitegmic ovule" is a key feature of all chloranthaceous plants. The word "ovule" and "ovules" have occurred four times in total in Friis et al (2019), but NONE in the figure captions. In the fossil description, they mentioned the word "ovule" but failed to cite any figure to support their claim.…”

“…The author has written to the International Journal of Plant Sciences, the University of Chicago Press, and the University Chicago on this issue. Only the chief editor of the International Journal of Plant Sciences responded by writing "We recently completed our investigation of your complaint, and did not find a basis for retracting Friis et al (2019)." The Press and University remain silent on this issue so far.…”

Multiparted, apocarpous flowers from the Early Cretaceous of eastern North America and Portugal

“…In terms of their organization and structure, Early Cretaceous angiosperm flowers range from simple forms with few parts, such as the chloranthoids Hedyflora E.M. Friis, P.r.CranE et K.r.PEdErsEn (unisexual) and Canrightiopsis E.M. Friis, G.W.GriMM, M.M.MEndEs et K.r.PEdErsEn (bisexual), to the more complex bisexual lauralean flowers of Saportanthus E.M.Friis, P.r.CranE et K.r.PEdErsEn with multiple parts and a syncarpous gynoecium (Friis et al 2015a(Friis et al , 2017a(Friis et al , 2019c. Also diverse during the Early Cretaceous are numerous multiparted flowers with apocarpous gynoecia.…”

Middle–Late Jurassic fossils from northeastern China reveal morphological stasis in the catkin-yew

“…In most cases, the credible fossil record of relictual genera such as Craigia (Malvaceae), Davidia (Nyssaceae), Cyclocarya (Juglandaceae) and Metasequoia (Cupressaceae) extends back to the early Cenozoic [ 8 ]. In a few other cases, the reliable fossil record of conifers such as Taiwania (Cupressaceae) and several angiosperm genera, such as Hedyosmum (Chloranthaceae) [ 9 ], extends back into the Cretaceous. However, there are few living genera of seed plants for which the fossil record extends back into the Jurassic, and still fewer that are well documented based on details of both leaves and reproductive structures.…”