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91.
《Palaeoworld》2016,25(1):104-115
Roses (Rosa, Rosaceae) are arguably the most admired ornamental plants in the world. Southwestern China is the center of diversity for many extant native species of Rosa and fossils found in this region are critical for understanding the evolution of this genus. Herein, we report a leaf fossil record with good preservation from the late Miocene of Yunnan Province. The opposite and odd-pinnate leaf is composed of seven elliptical leaflets, with close, crenulate, and regular marginal teeth. The stipules are lanceolate and adnate to the petiole. Additionally, the secondary veins are semicraspedodromous, showing the same venation pattern as most living Rosa species in southwestern China. On the basis of the extensive morphological comparisons, we propose a new species, R. fortuita T. Su et Z.K. Zhou n. sp. This is the first confirmed Rosa leaf fossil record in China, and the discovery of R. fortuita n. sp. indicates that Rosa existed in southwestern China by the late Miocene. It suggests that Rosa was distributed in subtropical or temperate forests and shared a similar ecological niche as Rosa in Europe during the Oligocene and Miocene. The modern diversification of Rosa in southwestern China is thought to have been closely associated with the continuous uplift of the Qinghai-Tibet Plateau since the late Miocene, creating complex topography and a variety of climate conditions. 相似文献
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豆科植物上单胞锈菌属—新变种和—中国新记录种(英文) 总被引:1,自引:0,他引:1
报道了豆科植物上单胞锈菌属1新变种和中国1新记录种。达乌里黄耆Astragalus dahuricus上的斑点单胞锈菌达乌里黄耆变种Uromyces punctatus var.dahuricus为新变种;山岩黄耆Hedysarum alpinum上的八岳山单胞锈菌Uromyces yatsugatakensis为中国新记录种。提供了详细的形态描述和线条图。研究标本保存在赤峰学院菌物标本室(CFSZ)和中国科学院菌物标本馆(HMAS)。 相似文献
95.
《Palaeoworld》2016,25(2):303-317
Despite the well-established phylogeny and good fossil record of branchiopods, a consistent macro-evolutionary timescale for the group remains elusive. This study focuses on the early branchiopod divergence dates where fossil record is extremely fragmentary or missing. On the basis of a large genomic dataset and carefully evaluated fossil calibration points, we assess the quality of the branchiopod fossil record by calibrating the tree against well-established first occurrences, providing paleontological estimates of divergence times and completeness of their fossil record. The maximum age constraints were set using a quantitative approach of Marshall (2008). We tested the alternative placements of Yicaris and Wujicaris in the referred arthropod tree via the likelihood checkpoints method. Divergence dates were calculated using Bayesian relaxed molecular clock and penalized likelihood methods. Our results show that the stem group of Branchiopoda is rooted in the late Neoproterozoic (563 ± 7 Ma); the crown-Branchiopoda diverged during middle Cambrian to Early Ordovician (478–512 Ma), likely representing the origin of the freshwater biota; the Phyllopoda clade diverged during Ordovician (448–480 Ma) and Diplostraca during Late Ordovician to early Silurian (430–457 Ma). By evaluating the congruence between the observed times of appearance of clade in the fossil record and the results derived from molecular data, we found that the uncorrelated rate model gave more congruent results for shallower divergence events whereas the auto-correlated rate model gives more congruent results for deeper events. 相似文献
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The distribution of the Karamoja Apalis Apalis karamojae, an East African endemic, has been sparsely documented in Uganda. In October 2011, a survey of the species was carried out near Iriiri in north-eastern Uganda. The main aim was to find out if there is a viable population of the species and to highlight the threats to its population. Sixteen 1-km transects in four sites were surveyed. The survey recorded nine individuals including a pair at an occupied nest, which is not conclusive for determining the viability of the population. The main threats to the species were cutting of the dominant shrub Vachellia drepanolobium (Acacia drepanolobium) in the area, farming and grazing. When we attempted luring the birds using the recorded song of the Karamoja Apalis from Tanzania, these individuals did not respond. We therefore recommend (1) to undertake a more detailed GIS survey to discover the extent of the suitable habitat, (2) to repeat the survey with improved effort to better estimate the viability of this population, (3) to conduct a study to ascertain the successful breeding of the species in the area, (4) to conduct a DNA analysis to compare the Iriiri population with the Tanzanian population, and (5) to record the song of the Ugandan birds for song analysis and to determine the response of Tanzanian birds. 相似文献
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正2015年6月22日,在河北省平山县驼梁国家级自然保护区驼峰附近的华北落叶松林内(113°49′33″E,38°44′59″N,海拔2 056 m)观察到1雌1雄2只鹟科鸟类。雌鸟上体橄榄褐色,两翼各具1道棕白色的翼斑;喉部、胸部浅褐色,并略带皮黄;尾上覆羽沾棕色;眼周白色,嘴黑褐色。雄鸟上体暗蓝灰色,喉、上胸、两胁橙红色,腹部颜色逐渐变白,尾近黑色。发现时,雌鸟往返飞行于落叶松枝和地面进行觅食;雄鸟在落叶松上部的树枝上频繁地鸣唱。经查阅文献(约翰·马敬能等2000,曲利明2014,Clement et al.2016),确定该鸟种为锈胸蓝姬鹟(Ficedula hodgsonii)(图1)。 相似文献
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Guillaume Guinot Lionel Cavin 《Biological reviews of the Cambridge Philosophical Society》2016,91(4):950-981
Actinopterygii (ray‐finned fishes) and Elasmobranchii (sharks, skates and rays) represent more than half of today's vertebrate taxic diversity (approximately 33000 species) and form the largest component of vertebrate diversity in extant aquatic ecosystems. Yet, patterns of ‘fish’ evolutionary history remain insufficiently understood and previous studies generally treated each group independently mainly because of their contrasting fossil record composition and corresponding sampling strategies. Because direct reading of palaeodiversity curves is affected by several biases affecting the fossil record, analytical approaches are needed to correct for these biases. In this review, we propose a comprehensive analysis based on comparison of large data sets related to competing phylogenies (including all Recent and fossil taxa) and the fossil record for both groups during the Mesozoic–Cainozoic interval. This approach provides information on the ‘fish’ fossil record quality and on the corrected ‘fish’ deep‐time phylogenetic palaeodiversity signals, with special emphasis on diversification events. Because taxonomic information is preserved after analytical treatment, identified palaeodiversity events are considered both quantitatively and qualitatively and put within corresponding palaeoenvironmental and biological settings. Results indicate a better fossil record quality for elasmobranchs due to their microfossil‐like fossil distribution and their very low diversity in freshwater systems, whereas freshwater actinopterygians are diverse in this realm with lower preservation potential. Several important diversification events are identified at familial and generic levels for elasmobranchs, and marine and freshwater actinopterygians, namely in the Early–Middle Jurassic (elasmobranchs), Late Jurassic (actinopterygians), Early Cretaceous (elasmobranchs, freshwater actinopterygians), Cenomanian (all groups) and the Paleocene–Eocene interval (all groups), the latter two representing the two most exceptional radiations among vertebrates. For each of these events along with the Cretaceous‐Paleogene extinction, we provide an in‐depth review of the taxa involved and factors that may have influenced the diversity patterns observed. Among these, palaeotemperatures, sea‐levels, ocean circulation and productivity as well as continent fragmentation and environment heterogeneity (reef environments) are parameters that largely impacted on ‘fish’ evolutionary history, along with other biotic constraints. 相似文献
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