您选择的条件: 昆虫学
  • 民勤温性荒漠草原拟步甲昆虫多样性调查

    分类: 生物学 >> 昆虫学 提交时间: 2023-05-30 合作期刊: 《干旱区研究》

    摘要: 为明确民勤温性荒漠草原拟步甲昆虫群落多样性及其时间动态,于2021年410月采用巴氏罐诱法对甘肃省民勤县砾质、沙质与盐土荒漠草地拟步甲科昆虫群落进行系统调查。(1)本次调查共捕获拟步甲科昆虫8492头,分属于8属10种,其中姬小胸鳖甲(Microdera elegans)和多毛宽漠甲(Sternoplax setosa setosa)为优势种,分别占总个体数的26.88%和25.07%,波氏真土甲(Eumylada potanini)为砾质荒漠草地的特有种。(2)3个亚类荒漠草地拟步甲昆虫物种数和个体数在7月达到峰值,10月降到最低。(3)砾质荒漠草地和沙质荒漠草地的拟步甲群落多度和香农多样性指数显著高于盐土荒漠草地(P<0.05);盐土荒漠草地的拟步甲群落丰富度显著高于沙质荒漠草地(P<0.05)。(4)相关性分析表明,拟步甲群落的丰度指数与植被群落高度、土壤含水量和植被盖度呈显著负相关(P

  • Survivors crossed the K-Pg extinction line and radiated in the Quaternary: Phylogenetic genomics of the Cimbicidae

    分类: 生物学 >> 昆虫学 提交时间: 2023-02-28

    摘要: The Cimbicidae are the physically largest members of the Hymenoptera. They are herbivorous sawflies with clubbed antennae. The previous classification maintained that this family contains four subfamilies. Two of them, the Cimbicinae and Abiinae, are richly diverse and distributed across the Holarctic. The Corynidinae are confined to the Palaearctic realm and primarily diversified around the Mediterranean and southwestern Asia, while the most morphologically primitive Pachylostictinae has a restricted distribution in South America. However, the connotation of these subfamilies and phylogenetic relationships among genera is still confusing, which limits the study of their evolutionary history and hypotheses of their particular origin. Here, we used the nuclear single-copy genes and mitochondrial genomes to trace the evolutionary history of the Cimbicidae and combine an extensive molecular dataset with phylogenetically and stratigraphically constrained fossil calibrations to deduce an evolutionary timescale for the Cimbicidae. We reveal that the Cimbicidae survived the Cretaceous-Palaeogene (K-Pg) extinction. After then, the lineages differentiation and the diversification of the extant genera gradually initiated in the earlier half of the Paleogene. However, the rapid diversification of the Cimbicidae was almost completed in the later half of Paleogene and the earlier half of Neogene (4010 Myr.). This fast and almost simultaneous genus-level diversity of Cimbicidae underscores the significance of the boundary of geological historical sequence in shaping the taxonomic hierarchy of insects.

  • The phylogenetic position of Cladiucha within Tenthredinidae based on comprehensive mitochondrial phylogenomics and the evidence from comparative analyses of rRNA secondary structure

    分类: 生物学 >> 昆虫学 提交时间: 2020-04-19

    摘要: Two mitogenomes of Cladiucha were newly reported and shown typical pattern of gene arrangement. The phylogenetic position of Cladiucha was obtained from tree reconstruction using various data treatment methods and substitution models. Significant heterogeneity in the nucleotide composition and mutational biases was found in the mitochondrial protein-coding genes, and the third codon position exhibited high levels of saturation. Therefore, 14 datasets were conducted under both site-homogeneous and site-heterogeneous models. The following conclusions were drawn from the phylogenetic analyses: (i) the monophyly of Tenthredinidae was confirmed, (ii) the monophyly of Allantinae + Tenthredininae + Megabelesinae was approved, and (iii) within the family, ((((Tenthredininae + Fenusinae) + Allantinae) + Megabelesinae) + Nematinae) is probably the most acceptable cladogram for the phylogeny of Tenthredinidae, which is also supported by the morphological analysis and a comparative study on the rRNA secondary structure. Divergence time estimation analyses indicated that diversification of the major superfamilies of the suborder Symphyta occurred around 232.9 Ma, and the splits of Tenthredinidae were dated to 146 Ma, which corresponding to the origin of the earliest lineages of flowering plants and major diversifications of core angiosperms, respectively. The Cladiucha arose in the Mid-Miocene; at that time, magnoliids are rapidly undergoing genus-species differentiation. "