Arthropod Structure & Development最新文献

Foregut anatomy and ultrastructure of the soil-spraying larvae of Bittacus cirratus Tjeder (Mecoptera: Bittacidae). 喷土螟螟幼虫前肠解剖及超微结构研究。

IF 1.3 3区农林科学 Q2 ENTOMOLOGY

Arthropod Structure & Development

Pub Date : 2026-03-17 DOI: 10.1016/j.asd.2026.101529

He-Hong Wang, Yue-Ling Wu, Bao-Zhen Hua

The larvae of Bittacidae in Mecoptera are remarkable for their distinctive soil-spraying behavior. To adapt the soil-spraying behavior, the larvae bear compact longitudinal muscles on the midgut, and well-developed circular muscles on the rectum. Whether the foregut evolved specific morphological adaptations associated with this behavior, however, remains unknown to date. In this study, the foregut of fourth-instar larvae of the hangingfly Bittacus cirratus Tjeder was investigated using light and transmission electron microscopy. The foregut comprises a short pharynx and a long esophagus. The esophagus is composed of a cuticular intima, a single layer of thin epithelial cells, and longitudinal and circular muscles. The cuticular intima thickens and differentiates into three layers: the endocuticle, exocuticle, and epicuticle. The epithelial cells are rich in mitochondria, microtubules, glycogen, and rough endoplasmic reticulum. The muscle cells are characterized by a particularly high density of myofibrils, along with distinct Z-lines and abundant mitochondria. The longitudinal and circular muscles are well-developed to support soil-spraying behavior, facilitating rapid soil transport through the esophagus, and the trilaminar intima protects the epithelium against abrasion by soil particles.

鞘翅目蠓科幼虫以其独特的喷土行为而引人注目。为了适应喷土行为，幼虫在中肠上有致密的纵向肌肉，在直肠上有发达的圆形肌肉。然而，前肠是否进化出了与这种行为相关的特定形态适应，至今仍不得而知。本研究采用光镜和透射电镜对垂蝇（Bittacus cirratus Tjeder） 4龄幼虫的前肠进行了研究。前肠包括短咽和长食道。食道由角质层内膜、单层薄上皮细胞、纵向和环状肌肉组成。角质层内膜增厚并分化为三层：囊内层、表皮层和表皮层。上皮细胞富含线粒体、微管、糖原和粗糙的内质网。肌细胞的特点是肌原纤维密度特别高，有明显的z线和丰富的线粒体。纵向和圆形肌肉发育良好，支持土壤喷洒行为，促进土壤通过食道的快速运输，三层内膜保护上皮免受土壤颗粒的磨损。

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引用次数: 0

The first comparison of the sperm ultrastructure of Lymexyloidea with Mordelloidea and Tenebrionoidea (Coleoptera) lymexylodae与mordellodae和tenbrionodae（鞘翅目）精子超微结构的首次比较。

IF 1.3 3区农林科学 Q2 ENTOMOLOGY

Arthropod Structure & Development

Pub Date : 2026-03-01 Epub Date: 2026-02-09 DOI: 10.1016/j.asd.2026.101507

Jan Batelka , David Mercati , Mariangela Gentile , Pietro Lupetti , Romano Dallai

The work has considered the sperm structure of Lymexyloidea to test the relationship of this group with Tenebrionoidea and the recently proposed "Mordelloid clade", consisting of the families Mordellidae and Ripiphoridae. The sperm structure of the Hylecoetidae Elateroides dermestoides partially supports the above mentioned relationship as it has a short sperm provided with a peculiar acrosome characterized by an electron-dense ring at half-length and a dot at the apex. The Mordellidae species examined, Curtimorda maculosa and Conalia baudii share the unique organization of the posterior flagellar region provided with only the 9 axonemal accessory tubules. Moreover, due to the sperm length, sperm looping is evident. The Ripiphoridae Pelecotoma fennica exhibits notably differences from Mordellidae species lacking the unusual structure of the flagellar posterior region. The sperm looping is, however, still evident.

本研究考虑了Lymexyloidea的精子结构，以检验该类群与拟甲黄总科（tenbrionoidea）以及最近提出的由拟甲黄科（Mordellidae）和拟甲黄科（Ripiphoridae）组成的“拟甲黄总支”的关系。Elateroides dermestoides的精子结构部分地支持了上述关系，因为它有一个短的精子，具有一个特殊的顶体，其特征是在半长处有一个电子密集的环，在顶端有一个点。所研究的Mordellidae种，Curtimorda maculosa和Conalia baudii具有独特的后鞭毛区组织，只有9个轴突附属小管。此外，由于精子的长度，精子环是明显的。在鞭毛后区缺乏不寻常的结构时，鞭毛瘤与鞭毛瘤有明显的区别。然而，精子的循环仍然很明显。

引用次数: 0

Comparative study of forewing surface ultrastructure in Eneopterinae crickets, with possible implication on male song frequency (Gryllidae, Eneopterinae) 蝶科蟋蟀前翅表面超微结构的比较研究及其对雄性鸣叫频率的影响

IF 1.3 3区农林科学 Q2 ENTOMOLOGY

Arthropod Structure & Development

Pub Date : 2026-03-01 Epub Date: 2026-02-12 DOI: 10.1016/j.asd.2026.101508

Louna Royer , Teddy Gaiddon , Tony Robillard

Acoustic signals play a key role in animal communication and are shaped by both sexual and natural selection. In crickets, males produce sound using specialized forewing structures, leading to a strong sexual dimorphism in forewing morphology and functioning. While the macroscopic structures of the forewings and sound-production mechanism are well understood, they have been little studied at the microscopic scale. Yet surface ultrastructure of the forewings’ membrane likely plays a role in shaping its physical properties and vibratory behavior. In the subfamily Eneopterinae, species belonging to the tribe Lebinthini show remarkable high-frequency calling songs that could be partly explained by differences in terms of surface ultrastructure. In the present study, we used scanning electron microscopy to compare male and female forewing membrane ultrastructure of 33 species of Eneopterinae crickets, including species producing low-frequency and high-frequency calling songs. We highlighted a great diversity of ultrastructure within the subfamily. Our results show remarkable differences between males and females of the non-lebinthini species concerning the hexagonal cells on the dorsal face of the forewings, and between the males of the different tribes. The presence of pronounced hexagonal cells in Lebinthini males (high-frequency singers), in contrast to the flattened harp membrane of non-Lebinthini species (low-frequency singers), added to the strong sexual dimorphism of the structures, suggests a link between the presence of these hexagonal structures and the sound-production mechanisms.

声音信号在动物交流中起着关键作用，并受到性选择和自然选择的影响。在蟋蟀中，雄性利用特殊的前翼结构发出声音，导致前翼形态和功能上强烈的两性二态性。虽然前翼的宏观结构和发声机制已经被很好地理解，但在微观尺度上的研究却很少。然而，前翼膜的表面超微结构可能在塑造其物理特性和振动行为方面起着重要作用。在蝶亚科中，属于Lebinthini部落的物种表现出显著的高频鸣声，这可以部分解释为表面超微结构的差异。本研究采用扫描电镜对33种印蝶科蟋蟀（包括发出低频鸣声和高频鸣声的蟋蟀）雌雄前翅膜的超微结构进行了比较。我们强调了亚家族内部超微结构的巨大多样性。结果表明，不同种群的雄性和雌性在前翅背面六角形细胞上存在显著差异，不同种群的雄性也存在显著差异。Lebinthini雄性（高频歌手）中明显的六角形细胞的存在，与非Lebinthini物种（低频歌手）扁平的竖琴膜形成鲜明对比，加上结构的强烈性别二态性，表明这些六角形结构的存在与声音产生机制之间存在联系。

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引用次数: 0

Comparative morphology of the labial gland in Formicidae 蚁科唇腺的比较形态学。

IF 1.3 3区农林科学 Q2 ENTOMOLOGY

Arthropod Structure & Development

Pub Date : 2026-03-01 Epub Date: 2026-02-09 DOI: 10.1016/j.asd.2026.101512

Liangliang Zhang, Xujin He, Ruoqing Ma, Hong He

The labial gland is an important exocrine gland in ants and is thought to contribute to food processing and trophallaxis. In this study, the morphology of the labial gland was examined in 12 species from 4 subfamilies—Ponerinae, Formicinae, Dolichoderinae, and Myrmicinae—using light and electron microscopy (SEM, TEM). Our results reveal that gland morphology is more similar among closely related species, suggesting a stronger correlation with phylogeny than with diet. The morphology also appears to relate to social behavior, particularly trophallaxis. Formicine species, which rely heavily on trophallaxis, possessed the largest relative reservoir size, whereas the two examined myrmicine species, which have reservoirs absent, are known to rely little or not at all on this behavior. Ultrastructural observations showed abundant rough endoplasmic reticulum in all species, indicating protein-rich secretions in the labial gland. Ponerine species displayed the acinar type, characterized by short microvilli in the apical cell region and a ramified canaliculi system that delivers secretion to the duct. Species from other subfamilies exhibited the tubular type, with long apical microvilli that increase the apical surface and appear to facilitate secretion discharge. This study provides new comparative data on labial gland morphology and reveals potential phylogenetic, behavioral, and ecological variation that will require further study to confirm and fully understand.

唇腺是蚂蚁重要的外分泌腺，被认为对食物加工和营养有贡献。本研究采用光镜和电子显微镜（SEM， TEM）对4个亚科（ponerinae, Formicinae, Dolichoderinae, myrmicinae） 12个种的唇腺形态进行了研究。我们的研究结果表明，在近亲物种中，腺体形态更相似，这表明与系统发育的关系比与饮食的关系更强。形态也似乎与社会行为有关，特别是营养性。严重依赖营养性的蚁甲物种拥有最大的相对储存库大小，而两种被研究的蚁甲物种没有储存库，已知很少依赖或根本不依赖这种行为。超微结构观察显示，所有物种均有丰富的粗面内质网，表明唇腺有富含蛋白质的分泌物。Ponerine种类表现为腺泡型，其特征是在顶端细胞区域有短的微绒毛和分支的小管系统，将分泌物输送到导管。其他亚科的种类表现为管状型，具有长长的顶端微绒毛，增加了顶端表面，似乎有利于分泌物的排出。本研究为唇腺形态学提供了新的比较数据，揭示了潜在的系统发育、行为和生态变化，这些变化需要进一步的研究来证实和充分理解。

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引用次数: 0

Ultrastructure and optical features of compound eyes in Odontothrips loti (Thysanoptera: Thripidae) 黄齿蓟马复眼的超微结构和光学特征。

IF 1.3 3区农林科学 Q2 ENTOMOLOGY

Arthropod Structure & Development

Pub Date : 2026-03-01 Epub Date: 2026-02-10 DOI: 10.1016/j.asd.2026.101510

Xu Ding , Ya-Rong Gu , Bai-Long Yang, Ying Miao

Thrips (Thysanoptera) are minute insects of ecological and economic importance, yet their visual systems remain poorly documented. Here, we present a comprehensive morphological and optical analysis of the compound eyes of Odontothrips loti, an important alfalfa pest, using scanning and transmission electron microscopy. The compound eyes of adult O. loti conform to the apposition type and contain 56–63 ommatidia per eye. Sexual dimorphism is evident, with females exhibiting larger facets than males. Each ommatidium comprises a cornea, a eucone-type crystalline cone, seven retinula cells, two primary pigment cells, and an undetermined number of secondary pigment cells. Quantitative measurements show relatively wide interommatidial (Δφ) and rhabdom acceptance angles (Δρ_rh), low F-numbers (F), and elevated eye parameter (P) values, which are optical characteristics frequently associated with strong size constraints in miniature insects. These findings reveal a compact visual system shaped by the morphological limitations imposed by miniaturization and contribute to a broader understanding of visual diversity in Thysanoptera.

蓟马（Thysanoptera）是一种微小的昆虫，具有重要的生态和经济意义，但它们的视觉系统仍然缺乏文献记载。本文利用扫描电镜和透射电镜对紫花苜蓿重要害虫牙蓟马的复眼进行了形态学和光学分析。成虫的复眼符合对偶型，每眼含有56 ~ 63条小眼。两性二态性是明显的，雌性表现出比雄性更大的面。每个小眼包括一个角膜、一个真锥型晶状体、七个视网膜细胞、两个初级色素细胞和数目不定的次级色素细胞。定量测量显示相对较宽的眼间（Δφ）和横纹肌接受角（Δρrh），较低的F值(F)和较高的眼参数(P)值，这些光学特征通常与小型昆虫的强尺寸限制有关。这些发现揭示了一个紧凑的视觉系统，该系统是由小型化造成的形态限制所形成的，有助于更广泛地了解囊翅目的视觉多样性。

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引用次数: 0

Ultrastructural diversity of compound eyes in Fulgoromorpha (Hemiptera): evidence for convergent and divergent evolutionary trends 半翅目狐形目复眼的超微结构多样性：趋同和分化进化趋势的证据

IF 1.3 3区农林科学 Q2 ENTOMOLOGY

Arthropod Structure & Development

Pub Date : 2026-03-01 Epub Date: 2026-02-12 DOI: 10.1016/j.asd.2026.101520

Wei Fang , Xiaohua He , Wenqian Wang , Yuqing Tang , Jianyu Bi , Thierry Bourgoin , Charles R. Bartlett , Daozheng Qin

The external morphology and ultrastructure of the compound eyes in adults of eight species of planthoppers were studied using scanning (SEM) and transmission (TEM) electron microscopy. The eyes are of the apposition type, and each ommatidium includes a laminated corneal lens, a crystalline cone, eight retinula cells, two primary pigment cells, 5–8 secondary pigment cells, and a basal lamina. Two distinct retinula cell patterns were observed: a "7 + 1" arrangement in studied specimens of Delphacidae and Tropiduchidae, and a "6 + 1 + 1" arrangement in those of Cixiidae, Meenoplidae, Fulgoridae, Ricaniidae, Flatidae, and Dictyopharidae. These structural differences are not consistently associated with taxonomic groupings and may reflect independent evolutionary developments. In particular, the "7 + 1" configuration in Tropiduchidae may have evolved independently from that in Delphacidae. At this stage, the ultrastructure of compound eyes exhibits unexpected and intriguing morphological variations; however, additional studies are necessary to fully capture the diversity of this ancient group before any attempt can be made to interpret these features in a phylogenetic context.

采用扫描电镜（SEM）和透射电镜（TEM）对8种飞虱成虫复眼的外部形态和超微结构进行了研究。眼为对位型，每个小眼包括一个层状角膜晶状体、一个晶状体、8个视网膜细胞、2个初级色素细胞、5-8个次级色素细胞和一个基底层。观察到两种截然不同的视网膜细胞模式：飞虱科和棘蝽科的视网膜细胞呈“7 + 1”排列，刺蝇科、刺蝇科、刺蝇科、刺蝇科、扁蝇科和刺蝇科的视网膜细胞呈“6 + 1 + 1”排列。这些结构上的差异并不总是与分类分组有关，可能反映了独立的进化发展。特别值得一提的是，Tropiduchidae的“7 + 1”结构可能是独立于Delphacidae进化而来的。在这个阶段，复眼的超微结构表现出意想不到的和有趣的形态变化；然而，在任何尝试在系统发育背景下解释这些特征之前，需要进一步的研究来充分捕捉这个古老群体的多样性。

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引用次数: 0

Structural morphology and light-induced changes in the apposition eye of Tomicus minor (Hartig) (Coleoptera: Curculionidae: Scolytinae) 小密蛾（Tomicus minor, Hartig）对位眼的结构形态及光致变化（鞘翅目：弯蝇科：弯蝇科）。

IF 1.3 3区农林科学 Q2 ENTOMOLOGY

Arthropod Structure & Development

Pub Date : 2026-03-01 Epub Date: 2026-02-09 DOI: 10.1016/j.asd.2026.101509

Hua Xie , Yuyun Wang , Xinyu Tang , Meiru Yang , Yanlin Zhang , Li Zheng , Zongbo Li

Tomicus minor, commonly known as the transverse shot hole borer, is the most destructive pest of Pinus yunnanensis in southwestern China, causing substantial tree mortality. Behavioral studies have confirmed its strictly diurnal flight patterns, suggesting a reliance on visual cues for host detection. We conducted a detailed examination of the compound eye morphology and optics of T. minor using light, scanning electron, and transmission electron microscopy. Each apposition eye contains about 230 ommatidia, showing slight sexual and lateral variations. Ommatidial facet shapes vary dorsoventrally: quadrilateral in the dorsal region, hexagonal and rounded in central-to-ventral regions, and pentagonal peripherally. Each ommatidium comprises a large corneal lens, an acone-type crystalline cone with four cells, and an open rhabdom with eight retinular cells (central R7-R8 surrounded by R1-R6). Changes in dark/light adaptation influence cone size/shape and rhabdom cross-section, thereby regulating photoreceptor light exposure. Key optical parameters, such as the F-number (1.17), interommatidial angle (2.70°), eye parameter (1.09 μm rad), and acceptance/interommatidial angle ratio (4.52), indicate high sensitivity and contrast perception in daylight, supporting the insect's diurnal behaviors. This research enhances understanding of coleopteran vision, provides a foundation for Tomicus photoreception investigations, and may guide pest management strategies that incorporate both olfactory and visual cues.

小飞蛾（Tomicus minor）是云南松（Pinus yunnanensis）在西南地区最具破坏性的害虫，造成大量树木死亡。行为学研究证实了它严格的昼夜飞行模式，表明它依赖视觉线索来检测宿主。我们使用光镜、扫描电子显微镜和透射电子显微镜对T. minor的复眼形态和光学进行了详细的检查。每个对置眼包含约230个小眼，表现出轻微的性别和侧面差异。孔面面形状在背侧各不相同：背侧区域为四边形，中央至腹侧区域为六边形和圆形，周围为五边形。每个小眼包括一个大的角膜晶状体，一个有4个细胞的圆锥型晶状体和一个有8个视网膜细胞的开放横纹肌（中央R7-R8被R1-R6包围）。暗/光适应的变化影响锥体大小/形状和横纹肌横截面，从而调节光感受器的光暴露。关键的光学参数，如f值（1.17）、眼间角（2.70°）、眼参数（1.09 μm rad）和接受/眼间角比（4.52），表明该昆虫在日光下具有高灵敏度和对比度感知，支持其昼夜行为。本研究增强了对鞘翅目目昆虫视觉的认识，为Tomicus的光接受研究提供了基础，并可指导结合嗅觉和视觉线索的害虫管理策略。

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引用次数: 0

Descriptive and comparative morphology of the head and mouthparts of the species of Minixi Giordani Soika (1978) (Hymenoptera, Vespidae, Eumeninae) 小蜂头和口器的描述和比较形态学（膜翅目，小蜂科，小蜂科）。

IF 1.3 3区农林科学 Q2 ENTOMOLOGY

Arthropod Structure & Development

Pub Date : 2026-01-01 Epub Date: 2025-12-15 DOI: 10.1016/j.asd.2025.101474

Letícia A. de Oliveira , Lucas F. Leitão , Paulo C. Reis-Venâncio , Régis F. Souza , Marcel G. Hermes

Representative morphological studies for Eumeninae wasps are scarce. Thereby, the present study aimed to describe and compare the head and mouthparts of the species of the genus Minixi, proposing potential characters for phylogenetic analyzes for the subfamily and a new clearing protocol adapted for morphologically similar groups. Descriptions of the morphology of the anterior and posterior regions of the head, mouthparts, as well as the proposition of new morphological terms, are presented as results. The morphological characteristics presented and discussed in this research have potential use in Eumeninae systematics. This study also presents a standardization of morphological terminology for the head and mouthparts structures of eumenine wasps.

有代表性的胡蜂形态学研究很少。因此，本研究旨在描述和比较Minixi属物种的头部和口器，为该亚科的系统发育分析提供潜在的特征，并为形态相似的类群提供新的清理方案。描述了头部，口器的前后区域的形态学，以及新的形态学术语的命题，作为结果呈现。本研究所提出和讨论的形态特征具有潜在的应用价值。本研究也提出了一个标准化的形态学术语的头和口器结构的黄蜂。

引用次数: 0

Coercive male genital structures expose concealed female genitalia in the water strider Chimarrhometra orientalis Distant, 1879 强制性的男性生殖器结构暴露了水黾Chimarrhometra orientalis Distant中隐藏的女性生殖器。

IF 1.3 3区农林科学 Q2 ENTOMOLOGY

Arthropod Structure & Development

Pub Date : 2026-01-01 Epub Date: 2026-01-03 DOI: 10.1016/j.asd.2025.101506

Dong Yeop Yang , Min Suk Oh , Myeongdong Jo , Byeongho Lee , Jaehyun Choi , Suraj Basnet , Indra Prasad Subedi , Seunghwan Lee , Chang S. Han

Sexual conflict over mating frequency is widespread in animals, driving the evolution of antagonistic traits in both sexes. In insects, this conflict is evident in the evolution of complex genital structures, where males evolve traits that facilitate forceful copulation and females evolve defences to resist unwanted mating. In water striders, such as Chimarrhometra orientalis, both sexes have evolved unique genital morphologies. Females possess concealed genitalia, likely to prevent superfluous copulation, while males have conspicuous antler- and hook-like genital processes. Through detailed behavioural observations and imaging, we suggest that males use these structures to forcefully expose female genitalia and achieve intromission, without any courtship behaviour. This strategy contrasts with behavioural counter-adaptations seen in other water strider species, where males use courtship signals to extract concealed female genitalia. Our findings provide direct evidence of genitalic counter-adaptations to concealed female genitalia in water striders and suggest that such sexually antagonistic evolution can only be revealed through the integration of behavioural and morphological studies. This work highlights the complexity of mating dynamics and underscores the importance of combining close behavioural observation with morphological analysis to understand the evolutionary arms race between the sexes.

交配频率上的性冲突在动物中很普遍，这推动了两性对抗特征的进化。在昆虫中，这种冲突在复杂生殖结构的进化中表现得很明显，雄性进化出促进有力交配的特征，而雌性进化出抵御不必要交配的防御能力。在水黾中，如东方嵌合体，两性都进化出了独特的生殖器形态。雌性拥有隐藏的生殖器，可能会防止多余的交配，而雄性则有明显的鹿角和钩状生殖器。通过详细的行为观察和成像，我们认为雄性利用这些结构强行暴露雌性生殖器并实现插入，而没有任何求爱行为。这种策略与其他水黾物种的行为反适应形成对比，在其他水黾物种中，雄性使用求爱信号来提取隐藏的雌性生殖器。我们的研究结果为水黾对隐藏的雌性生殖器的生殖反适应提供了直接证据，并表明这种性对抗进化只能通过行为和形态学的综合研究来揭示。这项工作强调了交配动力学的复杂性，并强调了将密切的行为观察与形态分析相结合的重要性，以了解两性之间的进化军备竞赛。

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引用次数: 0

Role of Hox genes in insect development and evolution Hox基因在昆虫发育和进化中的作用

IF 1.3 3区农林科学 Q2 ENTOMOLOGY

Arthropod Structure & Development

Pub Date : 2026-01-01 Epub Date: 2025-11-26 DOI: 10.1016/j.asd.2025.101495

Sunjie Chen , Shaohua Dong , Congnan Cen , Kai Sun , Xiaoping Yu

Hox genes encode a group of highly conserved transcription factors that play crucial roles in determine regional identity along the anterior-posterior axis in insects. Early studies identified Hox genes as spatially restricted regulators responsible for the proper development of insect body segments and appendages. Over the past two decades, investigations across a wide range of insect species have further demonstrated that Hox genes also regulate the development of distinct specialized structures and contribute to the formation of the nervous system. Substantial evidence suggests that Hox genes not only preserve the fundamental body plan but also contribute to the evolutionary diversification of morphology in insects. This review summarizes the research to date on Hox genes in insects, including their genomic organization, expression patterns, regulatory mechanisms, and functional roles, and highlights their significance in the morphological evolution of insects.

Hox基因编码了一组高度保守的转录因子，这些转录因子在决定昆虫前后轴的区域身份中起着至关重要的作用。早期的研究发现Hox基因是受空间限制的调节因子，负责昆虫身体部分和附属物的正常发育。在过去的二十年中，对各种昆虫物种的研究进一步表明，Hox基因还调节着不同的特殊结构的发育，并有助于神经系统的形成。大量证据表明，Hox基因不仅保存了昆虫的基本体型，而且对昆虫形态的进化多样化起着重要作用。本文综述了昆虫Hox基因的基因组组织、表达模式、调控机制和功能作用等方面的研究进展，并强调了Hox基因在昆虫形态进化中的重要意义。

引用次数: 0