Table of Contents

30 November 2015, Volume 53 Issue 6
Cover illustration: The importance of systematic collections in biology and society as illustrated in Fig. 1 of Wen et al. with the vast collections of the US National Herbarium (Fig. 2 in Wen et al.) as the background. See Wen et al., pp. 477–488 in this issue.
  • Jun Wen, Stefanie M. Ickert-Bond, Marc S. Appelhans, Laurence J. Dorr, Vicki A. Funk
    J Syst Evol. 2015, 53(6): 477-488.
    Systematic biology is a discipline rooted in collections. These collections play important roles in research and conservation and are integral to our efforts to educate society about biodiversity and conservation. Collections provide an invaluable record of the distribution of organisms throughout the world and through recent and geological time, and they are the only direct documentation of the biological, physical, and cultural diversity of the planet: past, present, and future. Recent developments in bioinformatics and cyberinfrastructure are transforming systematics by opening up new opportunities and as a result major digitization efforts have increasingly made available large amounts of biodiversity data. The collections-based systematics community needs to train the next-generation of systematists with integrative skills, address grand questions about biodiversity at different scales, develop a community-wide cyberinfrastructure, effectively disseminate systematic data to biologists and the public, and proactively educate the public and policy makers on the importance of systematics and collections in the biodiversity crisis of the Anthropocene. Specifically, we call for a new global Biodiversity CyberBank, comparable to GenBank for genetic data, to be the repository of all biodiversity data, as well as a World Organization of Systematic Biology to lead major initiatives of the field. We also outline a new workflow for taxonomic monographs, which utilizes both the traditional strengths of synthesizing diverse collections-based taxonomic data and the capacity of online resources and bioinformatics tools.
  • Research Articles
  • Wei Zhou, Meng-Meng Guan, Xun Gong
    J Syst Evol. 2015, 53(6): 489-498.
    Cycas chenii X. Gong & W. Zhou sp. nov., a new species of Cycas L., is described and illustrated here. The morphological and karyomorphological comparisons are made between C. chenii and the closely related taxa for defining its taxonomical status as a new species. Moreover, the phylogenetic position of C. chenii within 16Cycas species is determined using DNA sequences of two plastid regions, nuclear ribosomal internal transcribed spacers, and two nuclear regions. Cycas chenii is readily distinguished from the related C. guizhouensis K. M. Lan & R. F. Zou by an acaulescent stem. Phylogenetic evidence indicates that C. chenii is a distinct group related to C. guizhouensis in the Section Stangerioides. The distribution and conservation status of C. chenii are also discussed.
  • Hong-Hu Meng, Tao Su, Yong-Jiang Huang, Hai Zhu, Zhe-Kun Zhou
    J Syst Evol. 2015, 53(6): 499-511.
    Fossil fruits of Palaeocarya (Juglandaceae) are described from late Miocene sediments of southeastern Yunnan, China. The fruits present a tri-lobed wing consisting of an intact oblong-ovate middle lobe and two lateral lobes. The lobes are apically obovate, and have pinnate venation. The middle lobe is thicker at the base and gradually tapers to the apex. The nutlet, located at the base of the winged fruit, is round and hispid, and is subdivided by a septum into two compartments. Based on extensive morphological comparisons to previously documented fossil fruits, we found that the fossil fruits align most closely with members of the genusPalaeocarya, but have a unique combination of characters. Thus, we describe the fossils as a new species, Palaeocarya hispida sp. nov. This species represents an important range expansion for low-latitude occurrences of Palaeocarya in the late Miocene and therefore substantially improves our understanding of the biogeographic history of the genus. We propose that the wide distribution of Palaeocarya and relatively narrow distributions of close relatives, Engelhardia, Alfaropsis, and Oreomunnea, might be associated with a stepwise cooling and a major ice sheet expansion in the Antarctic and Arctic from the late middle Miocene to early Pliocene. In particular, the climatic oscillations during the Quaternary, such as the last glacial maximum, might have led to a decrease in the geographic distribution of Engelhardieae.
  • Qi Zhang, Hui-Yin Song, Zheng-Yu Hu, Guo-Xiang Liu
    J Syst Evol. 2015, 53(6): 512-519.
    A heterotrophic dinoflagellate was identified as Diplopsalis caspica Ostenfeld by morphological characteristics, with the plate formula: Po, x, 3′, 1a, 6″, 4c, 4s, 5″′, 1″″. The newly recorded dinoflagellate was encountered during autumn in the phytoplankton community of Jihongtan Reservoir and some small ponds near the reservoir in Shandong Province, China. The species had been reported only in brackish ecosystems; however, our material fit with D. caspica occurred in freshwater habitat. The phylogenetic relationship of D. caspica was elucidated through small and large subunit ribosomal DNA sequences. In small and large subunit ribosomal DNA phylogenies, all Protoperidiniaceae species, including diplopsalids and Protoperidinium Bergh, could cluster into a monophyletic group. The molecular phylogenies indicated that the genus Diplopsalis would provide a link to the common ancestor of the Peridinium Ehrenberg and the Protoperidinium.
  • Jia-Bin RenYan-Ping Guo
    J Syst Evol. 2015, 53(6): 520-528.
    Asteraceae are distinguishable by their head-like inflorescence called a capitulum. There are a variety of capitulum types due to different combinations of different composing florets. Morphological evolution of capitula must involve homoplasy under selective constraints. Therefore, a comparative examination of ontogenies of divergent capitula among phylogenetically close taxa is important to investigate the genetic and molecular bases of this trait. In the subtribe Artemisiinae, tribe Anthemideae, three closely related genera have different flower heads: Chrysanthemum with the radiate, Ajania with the disciform, and Stilpnolepis with the discoid capitula. Through observations using scanning electron microscopy, we examined the morphogenetic processes of flower heads of representative species of these genera. The morphological differentiation of the discoid from the radiate/disciform capitula occurred early in the floral initiation stage. The development of the ray/marginal florets of the radiate/disciform capitula lagged behind the outermost disc florets throughout the phases of floral initiation and floral organogenesis. Primordia of their 1–2 dorsal corolla lobes and all stamens ceased to grow soon after initiation. In contrast, all florets on a discoid capitulum developed equally in rates and modes into bisexual actinomorphic flowers. Differentiation between the radiate and the disciform capitula occurred late during the floral maturation stage. Our data provided evidence to the interpretation that uniformly acropetal development only occurs in species with homogamous flower heads, and to the idea that the timing of ontogenetic divergence between taxa is positively correlated with the phylogenetic distance of the taxa.
  • Cai-Rong Yang, Hai-Qin Zhang, Fu-Qiang Zhao, Xiao-Yan Liu, Xing Fan, Li-Na Sha, Hou-Yang Kang, Yi Wang, Yong-Hong Zhou,
    J Syst Evol. 2015, 53(6): 529-534.
    Elymus tangutorum (Nevski) Hand.-Mazz (2n = 6x = 42) is a perennial species in the tribe Triticeae, which distributes in Nepal and north and northwest China. However, the genome constitution of E. tangutorum is controversial and its taxonomic status is not clear. Hybridizations of E. tangutorum were carried out with E. wawawaiensis J. R. Carlson & Barkworth (StH), Roegneria grandis Keng (StY), and E. dahuricus Turcz. ex Griseb. (StYH). Meiotic pairing in the hybrids E. tangutorum× E. wawawaiensis (StH), E. tangutorum × R. grandis (StY), and E. tangutorum× E. dahuricus (StYH) averaged 10.48, 11.12, and 20.92 bivalents per cell, respectively. The results suggested that E. tangutorum is an allohexaploid and contains the StYH genomes. Results of genomic in situ hybridization analysis strongly supported the chromosome pairing data. Therefore, E. tangutorum should be treated as Campeiostachys dahurica var. tangutorum (Nevski) B. R. Baum, J. L. Yang & C. Yen. Intergenomic rearrangements of E. tangutorum may be affected by environmental factors.
  • Sheng-Bin Chen, J. W. Ferry Slik, Jie Gao, Ling-Feng Mao, Meng-Jie Bi, Meng-Wei Shen, Ke-Xin Zhou
    J Syst Evol. 2015, 53(6): 535-545.
    It remains unclear whether the latitudinal diversity gradients of micro- and macro-organisms are driven by the same macro-environmental variables. We used the newly completed species catalog and distribution information of bryophytes in China to explore their spatial species richness patterns, and to investigate the underlying roles of energy availability, climatic seasonality, and environmental heterogeneity in shaping these patterns. We then compared these patterns to those found for woody plants. We found that, unlike woody plants, mosses and liverworts showed only weakly negative latitudinal trends in species richness. The spatial patterns of liverwort richness and moss richness were overwhelmingly explained by contemporary environmental variables, although explained variation was lower than that for woody plants. Similar to woody plants, energy and climatic seasonality hypotheses dominate as explanatory variables but show high redundancy in shaping the distribution of bryophytes. Water variables, that is, the annual availability, intra-annual variability and spatial heterogeneity in precipitation, played a predominant role in explaining spatial variation of species richness of bryophytes, especially for liverworts, whereas woody plant richness was affected most by temperature variables. We suggest that further research on spatial patterns of bryophytes should incorporate the knowledge on their ecophysiology and evolution.
  • GaneshPrasad ArunKumar, Lan-Hai Wei, Valampuri John Kavitha, Adhikarla Syama, Varatharajan Santhakumari Arun, Surendra Sathua, Raghunath Sahoo, R. Balakrishnan, Tomo Riba, Jharna Chakravarthy, Bapukan Chaudhury, Premanada Panda, Pradipta K Das, Prasanna K Nayak, Hui Li, Ramasamy Pitchappan, The Genographic Consortium
    J Syst Evol. 2015, 53(6): 546-560.
    The origin and dispersal of Y-Chromosomal haplogroup O2a1-M95, distributed across the Austro Asiatic speaking belt of East and South Asia, are yet to be fully understood. Various studies have suggested either an East Indian or Southeast Asian origin of O2a1-M95. We addressed the issue of antiquity and dispersal of O2a1-M95 by sampling 8748 men from India, Laos, and China and compared them to 3307 samples from other intervening regions taken from the literature. Analyses of haplogroup frequency and Y-STR data on a total 2413 O2a1-M95 chromosomes revealed that the Laos samples possessed the highest frequencies of O2a1-M95 (74% with >0.5) and its ancestral haplogroups (O2*-P31, O*-M175) as well as a higher proportion of samples with 14STR-median haplotype (17 samples in 14 populations), deep coalescence time (5.7 ± 0.3 Kya) and consorted O2a1-M95 expansion evidenced from STR evolution. All these suggested Laos to carry a deep antiquity of O2a1-M95 among the study regions. A serial decrease in expansion time from east to west: 5.7 ± 0.3 Kya in Laos, 5.2 ± 0.6 in Northeast India, and 4.3 ± 0.2 in East India, suggested a late Neolithic east to west spread of the lineage O2a1-M95 from Laos.