Lomonosov Moscow State University, Moscow, Russia.
Arthropod Struct Dev. 2010 Jan;39(1):52-69. doi: 10.1016/j.asd.2009.08.005. Epub 2009 Nov 5.
The first detailed morphological study of larvae, pupae and adults of a species of the hooded beetles (Coleoptera: Corylophidae) -Sericoderus lateralis - is presented. Histological sectioning, scanning and transmission electron microscopy, laser confocal microscopy and 3D-computer reconstruction were used. For the first time we report that according to the morphometric data of S. lateralis, at least some corylophid beetles have three larval stages. A phylogenetic position of Corylophidae within a cucujoid-cleroid clade is confirmed, and also the placement of Sericoderini within a corlyophid subgroup, which does not include Periptycinae and Foadiini. The larvae of Sericoderus are mainly characterized by plesiomorphic features compared to those of other corylophid tribes, notably Peltinodini and Rypobiini. Morphological and developmental consequences of miniaturization are discussed. Corylophid beetles display much less specific and far-reaching morphological consequences of miniaturization compared to Ptiliidae. We report the presence of unique modifications in the neural system not shared with any other insects, such as a distinctly asymmetric supraoesophageal ganglion in first instar larva, and a total displacement of the brain to the thorax in the adult stage. A highly unusual feature of the digestive tract is the sclerotised, V-shaped ventral wall of the pharynx. Developmental and size dependent changes in the relative volume of different organs are addressed. All organ systems change allometrically in the development of S. lateralis. Allometric trends in the volume of organs confirm that the factors limiting miniaturization are the size of the neural system, associated with the number and size of neurons (most critical for first instar larva), the mass of the skeleton, the egg size, and consequently the volume of the reproductive system (for free-living insects).
本文对一种兜甲科（鞘翅目：兜甲科）的幼虫、蛹和成虫进行了详细的形态学研究- Sericoderus lateralis 。使用了组织切片、扫描和透射电子显微镜、激光共聚焦显微镜和 3D 计算机重建。我们首次报道，根据 S. lateralis 的形态测量数据，至少一些兜甲科甲虫具有三个幼虫阶段。 Corylophidae 在 cucujoid-cleroid 分支中的系统发育位置得到确认，Sericoderini 也在一个不包括 Periptycinae 和 Foadiini 的兜甲科亚群中。与其他兜甲科部落相比， Sericoderus 的幼虫主要具有原始特征，特别是 Peltinodini 和 Rypobiini 。讨论了微型化的形态和发育后果。与 Ptiliidae 相比，兜甲科甲虫的微型化具有较少的特异性和深远的形态后果。我们报告了神经系统中存在独特的改变，这些改变与任何其他昆虫都不同，例如在第一龄幼虫中明显不对称的上颚神经节，以及在成虫阶段大脑完全移位到胸部。消化道的一个非常不寻常的特征是咽部硬化的 V 形腹壁。还研究了不同器官相对体积随发育和大小的变化。在 S. lateralis 的发育过程中，所有器官系统都以异速生长的方式发生变化。器官体积的异速生长趋势证实，限制微型化的因素是神经系统的大小，与神经元的数量和大小（对第一龄幼虫最为关键）、骨骼的质量、卵的大小以及生殖系统的体积（对于自由生活的昆虫）有关。
