This study examines phylogenetic relationships among the 12 genera of Urticeae (Urticaceae) and investigates the pattern of morphological evolution based on analysis of nuclear ribosomal internal transcribed spacer (nrITS) and two plastid DNA regions (rbcL exon, trnL-F spacer). Sequence data were analyzed using maximum parsimony and Bayesian inference, and selected morphological traits were mapped onto the molecular tree. The molecular results strongly supported monophyly of Urticeae, excluding Gyrotaenia, which is related to Elatostemateae. All genera were monophyletic except for Urtica, Laportea, and Urera. Two Hesperocnide species are nested within Urtica. Laportea and Urera are divided into three groups with a strong geographical signal. The inferred phylogeny indicates five well-supported clades in Urticeae: clade A including Urtica (with Hesperocnide), Zhengyia, Laportea I, and Nanocnide; clade B comprising Dendrocnide and Discocnide; clade C including only Girardinia; clade D including Laportea II; and clade E including Obetia, Urera I, II, III, and Poikilospermum. Although it is difficult to identify morphological synapomorphies for these well-defined clades within Urticeae, character analysis shows that the herbaceous habit and alternate leaves are the ancestral states in the tribe. The presence of stinging hairs is the derived status in Urticeae, and it might have been a key innovation triggering species diversification in the tribe.
Mazaceae, a recently proposed family in the Lamiales, contains three genera; Mazus, Lancea and Dodartia, yet the systematic position and the circumscription of the family have not been fully confirmed. This paper reports on an expanded analysis of the family that included most species of all three genera using five chloroplast DNA regions (matK, psbA‐trnH intergenic spacer, rbcL, rps16, trnL‐F intergenic spacer) and ITS of nrDNA to determine the phylogenetic placement of Mazaceae as well as the intrageneric relationships within the relatively large genus Mazus. The results support the recognition of the three genera (Mazus, Lancea, Dodartia), confirm the well‐supported monophyly of Mazaceae and show Lancea and Dodartia to be clustered together and sister to Mazus. The phylogenetic relationships within the Lamiales is highly congruent with previous molecular studies, with Mazaceae sister to a clade comprising Orobanchaceae, Phrymaceae and Paulowniaceae. Together they are sister to the rest of the families in the order. In Mazus, two major lineages were recognized, corresponding to the distribution ranges in Australia and Asia. Previous sectional treatments of Mazus are discussed in light of our molecular phylogenetic results. This study confirms the systematic position of Mazaceae within the Lamiales. The intrageneric relationships revealed in Mazus will provide evidence for further taxonomic studies of the genus.
A distinctive, previously undescribed species of Epimedium (Berberidaceae), which we propose naming E. tianmenshanensis, was found during a floristic survey in Hunan, China. It is similar to E. baojingense and E. franchetii, but has smaller flowers and petals with a short, blunt spur. We determined the phylogenetic position of the new species using DNA sequences of nuclear ITS and two chloroplast regions (atpB-rbcL intergenic spacer and matK). Molecular evidence indicates that E. tianmenshanensis occupies a distinct group related to E. baojingense.
Zhengyia shennongensis is described here as a new genus and species of the nettle family (Urticaceae) from Hubei province, central China. The phylogenetic position of Z. shennongensis is determined using DNA sequences of nuclear ribosomal ITS and three plastid regions (rbcL, psbA–trnH, trnL–F). Zhengyia shennongensis is readily distinguished from the related genera Urtica, Hesperocnide, and Laportea in the tribe Urticeae by its seed (oblong–globose or subglobose and not compressed achenes, surface densely covered with nipple–shaped protuberances) and stipule morphology (large leaf–like stipules with auriculate and amplexicaulous base and united with stem). Phylogenetic evidence indicates that Zhengyia is a distinct group related to Urtica (including Hesperocnide) species and Laportea cuspidata in tribe Urticeae. The bulbiliferous species of the tribe (L. bulbifera, L. cuspidata, Z. shennongensis) do not form a clade. This result indicates that the bulbil trait evolved in parallel within Urticeae. Our findings highlight the importance of shady and moist habitats in promoting species diversification and the parallel evolution of morphological traits that are likely to be adaptive.
Mazus lanceifolius (Mazaceae) is a perennial herb with opposite leaves and endemic to central China that has not been collected for 130 years. Rediscovery of this enigmatic species in the wild allows for determination of its phylogenetic position within Mazaceae. Phylogenetic reconstruction of Mazaceae based on DNA sequences from four plastid markers (matK, rbcL, rps16 and trnL-trnF) and nuclear ribosome ITS consistently showed that Mazus was not monophyletic. Mazus lanceifolius is in the most basal clade within Mazaceae, as sister to the remaining species of three recognized genera Dodartia, Lancea and Mazus. These results support the separation of M. lanceifolius from Mazus as a new genus, which was established here as Puchiumazus Bo Li, D.G. Zhang & C.L. Xiang. Meanwhile, a collection from Shennongjia Forestry District of Hubei Province, China, misidentified as “M. lanceifolius” in previous molecular study, is here revealed to represent an undescribed species of Mazus, i.e., M. fruticosus Bo Li, D.G. Zhang & C.L. Xiang, sp. nov. Morphologically, Puchiumazus is clearly distinct from the other three genera by having quadrangular to somewhat ribbed stems, and obviously opposite leaves. In addition, we provide a taxonomic key to the four genera of Mazaceae.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.