Department of Entomology and Nematology, University of California, Davis, Davis, California, USA.
Department of Biology, Division of Ecology, Evolution & Diversity Conservation, Zoological Institute, University of Leuven, Leuven, Belgium.
J Morphol. 2022 Jun;283(6):693-770. doi: 10.1002/jmor.21471. Epub 2022 Apr 29.
Recent studies of insect anatomy evince a trend towards a comprehensive and integrative investigation of individual traits and their evolutionary relationships. The abdomen of ants, however, remains critically understudied. To address this shortcoming, we describe the abdominal anatomy of Amblyopone australis Erichson, using a multimodal approach combining manual dissection, histology, and microcomputed tomography. We focus on skeletomusculature, but additionally describe the metapleural and metasomal exocrine glands, and the morphology of the circulatory, digestive, reproductive, and nervous systems. We describe the muscles of the dorsal vessel and the ducts of the venom and Dufour's gland, and characterize the visceral anal musculature. Through comparison with other major ant lineages, apoid wasps, and other hymenopteran outgroups, we provide a first approximation of the complete abdominal skeletomuscular groundplan in Formicidae, with a nomenclatural schema generally applicable to the hexapod abdomen. All skeletal muscles were identifiable with their homologs, while we observe potential apomorphies in the pregenital skeleton and the sting musculature. Specifically, we propose the eighth coxocoxal muscle as an ant synapomorphy; we consider possible transformation series contributing to the distribution of states of the sternal apodemes in ants, Hymenoptera, and Hexapoda; and we address the possibly synapomorphic loss of the seventh sternal-eighth gonapophyseal muscles in the vespiform Aculeata. We homologize the ovipositor muscles across Hymenoptera, and summarize demonstrated and hypothetical muscle functions across the abdomen. We also give a new interpretation of the proximal processes of gonapophyses VIII and the ventromedial processes of gonocoxites IX, and make nomenclatural suggestions in the context of evolutionary anatomy and ontology. Finally, we discuss the utility of techniques applied and emphasize the value of primary anatomical research.
最近对昆虫解剖学的研究表明，人们越来越倾向于综合和整体地研究个体特征及其进化关系。然而，蚂蚁的腹部仍然严重研究不足。为了解决这一不足，我们采用多模态方法，结合手动解剖、组织学和微计算机断层扫描，描述了 Amblyopone australis Erichson 的腹部解剖结构。我们专注于骨骼肌肉系统，但另外还描述了侧体和体后外分泌腺，以及循环、消化、生殖和神经系统的形态。我们描述了背血管的肌肉和毒液和 Dufour 腺的导管，并描述了内脏肛门肌肉。通过与其他主要蚂蚁谱系、蚁科和其他膜翅目外群进行比较，我们提供了 Formicidae 中完整的腹部骨骼肌肉原基的初步近似，同时提供了一个通常适用于六足动物腹部的命名方案。所有骨骼肌肉都可以与其同源物相对应，而我们观察到生殖器骨骼和蜇刺肌肉中存在潜在的进化特征。具体来说，我们提出第八对coxocoxal 肌肉是蚂蚁的一个synapomorphy；我们考虑了可能导致胸骨附肢在蚂蚁、膜翅目和六足动物中分布状态的转化系列；并讨论了 vespiform Aculeata 中第七对胸骨-第八对生殖节肌肉可能的synapomorphic 缺失。我们在膜翅目中同源化了产卵器肌肉，并总结了整个腹部的证明和假设的肌肉功能。我们还对 gonapophyses VIII 的近端突起和 gonocoxites IX 的腹侧突起进行了新的解释，并在进化解剖学和本体论的背景下提出了命名建议。最后，我们讨论了所应用技术的实用性，并强调了基础解剖学研究的价值。
