Paleoaltingia gen. nov., a new genus of Altingiaceae from the Late Cretaceous of New Jersey

Premise Altingiaceae is a small family with a bimodal Northern Hemisphere distribution in eastern North America and eastern Asia, and a rich Cenozoic fossil record. The charcoalified fossil infructescence Paleoaltingia gen. nov. from Turonian (Late Cretaceous) deposits of New Jersey, provides new evidence of early Altingiaceae reproductive structures and has biogeographical implications in understanding modern distribution. Methods Fossils were prepared using standard methods for obtaining and processing mesofossils. The fossils were examined with light microscopy, and scanning electron microscopy for observing structural and anatomical details. Phylogenetic analyses were performed using a combined matrix of molecular and morphological data. Results Based on morphological features of the fossil and the phylogenetic analyses, the new genus, Paleoaltingia, with two species (Paleoaltingia ovum-dinosauri and P. polyodonta) is erected. The phylogenetic position of Paleoaltingia confirms affinities with living Altingiaceae. Conclusions The combination of characters-simple capitate infructescence, syncarpous bicarpellate, and bilocular ovary, unique sterile phyllome structures-indicates that the fossil taxa have close affinities to modern Altingiaceae. The unique characters of the phyllomes provide new information on the floral diversity of Altingiaceae. The emergence of Paleoaltingia in Late Cretaceous sediments of Northeastern North America represents the earliest fossil record of Altingiaceae and provides new insights into its biogeography

Monophyly or Paraphyly– The Taxonomy of <em>Holcoglossum</em> (Aeridinae: Orchidaceae)

<div><p>Recently, there have been a lot of intense debates about the acceptance/rejection of paraphyletic groups in biological classification. On the one hand, evolutionary classification states that similarity and common descent are two criteria for biological classification and paraphyletic groups are natural units of biological classification. On the other hand, cladistic classification considers that common descent is the only criterion in biological classification and monophyly should be strictly adhered to. <em>Holcoglossum</em> is used herein as a case to illustrate this problem. Although <em>Holcoglossum</em> is a small orchid genus of less than 20 species, there is little consensus about its generic circumscription since it was established, which leads to confusion in taxonomic treatments in the <em>Aerides-Vanda</em> group. Based on the analyses of molecular and morphological evidence, our results suggest that the clade comprising <em>Holcoglossum</em> s.s., <em>Ascolabium</em>, <em>Penkimia</em> and <em>Ascocentrum himalaicum</em> is strongly supported as a monophyly, and that the three taxa are nested within different subclades of <em>Holcoglossum</em> s.s. Thus, it is reasonable to recognize a monophyletic circumscription of <em>Holcoglossum</em>, which is also well supported by some vegetative and floral characters. The <em>Holcoglossum</em> s.l. would facilitate a better understanding of pollinator-driven floral divergence and vegetative stasis than a paraphyletic and narrowly defined genus.</p> </div

Average pairwise sequence distances between <i>Holcoglossum</i> s.s. and related genera.

<p>Average pairwise sequence distances between <i>Holcoglossum</i> s.s. and related genera.</p

Pollinia of <i>Holcoglossum</i> and its alliance.

<p>A–B. <i>H. amesianum</i>; C–D. <i>H. himalaicum</i>; E–F. <i>H. kimabllianum</i>; G–H. <i>H. nujiangense</i>; I–J. <i>H. omeiense</i>; K–L. <i>H. rupestre</i>; M–N. <i>Vanda pumila</i>; O–P. <i>Aerides rosea</i>.</p

The 50% consensus Bayesian Inference and strict consensus maximum parsimony tree of <i>Holcoglossum</i> s.l.

<p>A. the combined DNA dataset, B. DNA and morphology dataset. The bootstrap percentages and posterior probability of >50% are shown above each branch.</p

Dendrograms of relationships among <i>Holcoglossum</i>.

<p>A. Cladogram from Bayesian inference, B: Corresponding patrocladogram with equal weight.</p

Relationships between pollination and flower color in <i>Holcoglossum</i>.

<p>The left panel shows diversity of the pollination types, and the right panel indicates the evolution of flower color.</p