The sperm structure of Embioptera (Insecta) and phylogenetic considerations

Dallai, Romano; Machida, Ryuichiro; Jintsu, Yoshie; Frati, Francesco; Lupetti, Pietro

doi:10.1007/s00435-007-0030-8

Cited by 15 publications

(14 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…), Mastotermes (basal group of termites), Embioptera (web spinners) (Dallai et al. ), a subgroup of Zoraptera (Dallai et al. , ), and in certain Plecoptera (Baccetti et al.…”

Section: Resultsmentioning

confidence: 99%

“…An acrosome shaped to fit into a cavity of the nucleus is described for Embioptera (Dallai et al. ). An extension along the longitudinal axis of the sperm in Haplothrips (Thysanoptera), and an extension along the nucleus in Hemiptera, Psocodea and Diptera. *Extracellular cylinder adhering to the acrosome: (0) absent; (1) present.…”

Section: Resultsmentioning

confidence: 99%

“…An asymmetric position is found in Scutigerella (Dallai and Afzelius ) and Embioptera (Dallai et al. ). *Coiling of acrosome and nucleus: (0) not coiled; (1) both helically coiled and enclosed by a sheath of microtubules. A helically coiled nucleus enclosed by a sheath of microtubules occurs in Archaognatha (jumping bristletails) (Jamieson et al.…”

Section: Resultsmentioning

confidence: 99%

“…Present in Embioptera and Phasmatodea (Dallai et al. ; Gottardo et al. ). Puff‐like expansion associated to the accessory bodies: (0) absent; (1) present.…”

Section: Resultsmentioning

confidence: 99%

See 3 more Smart Citations

The evolution of insect sperm − an unusual character system in a megadiverse group

Gottardo

Dallai

Mercati

et al. 2016

J Zool Syst Evol Res

Self Cite

View full text Add to dashboard Cite

Spermatozoa provide an unusual character system, with a limited number of components organized in a single cell. Similar spermatozoa occur in groups widely separated in the phylogenetic tree of Metazoa. Nevertheless, the character system contains phylogenetic information. Hexapoda have acquired spermatophores along with the switch from aquatic to terrestrial habitats, and related to this, a multitude of different sperm types. The aim of this study is a formal evaluation of the phylogenetic information content of spermatozoa. For the first time, sperm characters are coded for formal phylogenetic analyses. Different approaches are used and compared. Mainly due to a high level of homoplasy, the evaluation of sperm characters alone is insufficient for a reconstruction of the phylogeny of the group. Yet, a reliable reconstruction of the evolution of insect sperm is possible when character transformations are assessed using a phylogeny based on extensive molecular data. Important changes took place in the early evolution of Hexapoda. Sperm characters support some major clades (e.g. Hexapoda, Dicondylia, Polyneoptera, Psocodea), but important steps in the evolution are not reflected by transformations of spermatozoa, notably the rise of Pterygota or Holometabola. Important innovations are the formation of mitochondrial derivatives and the acquisition of accessory microtubules. Some features are conservative, whereas others evolved rapidly (e.g. presence or absence of the acrosome vesicle). Some groups are conservative in their sperm features (e.g. Odonata, Heteroptera), whereas the evolution of spermatozoa was distinctly accelerated in others (e.g. Ephemeroptera). The rate of evolution can change drastically in closely related groups. Profound changes in the morphologically uniform Zoraptera underline that sperm evolution can follow a pattern very different from the general somatic morphology. The mode of character reconstruction preferred here will be useful for the evaluation of specialized morphological character systems and strengthen the concept of evolutionary morphology.

show abstract

“…), Mastotermes (basal group of termites), Embioptera (web spinners) (Dallai et al. ), a subgroup of Zoraptera (Dallai et al. , ), and in certain Plecoptera (Baccetti et al.…”

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

“…Present in Embioptera and Phasmatodea (Dallai et al. ; Gottardo et al. ). Puff‐like expansion associated to the accessory bodies: (0) absent; (1) present.…”

Section: Resultsmentioning

confidence: 99%

See 2 more Smart Citations

The evolution of insect sperm − an unusual character system in a megadiverse group

Gottardo

Dallai

Mercati

et al. 2016

J Zool Syst Evol Res

Self Cite

View full text Add to dashboard Cite

show abstract

“…However, some promising studies clearly demonstrate that ultrastructural character complexes can be used with great success for resolving phylogenetic relationships among taxa, e.g. ultrastructure of the rhabdom of Heteroptera [28] or the sperm structure of Embioptera [29]. …”

Section: Discussionmentioning

confidence: 99%

Three-dimensional reconstruction on cell level: case study elucidates the ultrastructure of the spinning apparatus of Embia sp. (Insecta: Embioptera)

2016

View full text Add to dashboard Cite

Spinning is a phenomenon not only present in spiders, but also in many other arthropods. The functional morphology and complexity of spinning organs is often poorly understood. Their elements are minute and studying them poses substantial methodological difficulties. This study presents a three-dimensional reconstruction of a silk gland of Embia sp. on cellular level, based on serial sections acquired with serial block-face scanning electron microscopy (SBFSEM) to showcase the power of this method. Previous studies achieved either high resolution to elucidate the ultrastructure or satisfying three-dimensional representations. The high-resolution achieved by SBFSEM can be easily used to reconstruct the three-dimensional ultrastructural organization of cellular structures. The herein investigated spinning apparatus of Embioptera can be taken as an example demonstrating the potential of this method. It was possible to reconstruct a multinucleated silk gland containing 63 nuclei. We focused on the applicability of this method in the field of morphological research and provide a step-by-step guide to the methodology. This will help in applying the method to other arthropod taxa and will help significantly in adapting the method to other animals, animal parts and tissues.

show abstract

Sperm ultrastructure of Panorpodes kuandianensis (Mecoptera: Panorpodidae)

Zhang

Hua

2014

Microscopy Res & Technique

View full text Add to dashboard Cite

The sperm ultrastructure of the short-faced scorpionfly Panorpodes kuandianensis Zhong et al. was investigated using transmission electron microscopy. The spermatozoon is composed of a short head containing a bilayered acrosome and an elongate nucleus, a neck transition region, and a long flagellum. The acrosome consists of an acrosomal vesicle and a central perforatorium. The nucleus has two deep, U-shaped lateral grooves and its chromatin contains a series of parallel, regularly arrayed nuclear fibers. The barrel-shaped centriolar adjunct occupies the most volume of the neck region. The flagellum is helical for its whole length and is formed by an axoneme, two mitochondrial derivatives, a pair of accessory bodies, and peculiar accessory structures. The axoneme has nine accessory microtubules at the anterior flagellum region, displaying a 9 + 9 + 2 microtubular pattern, but the accessory microtubules are short and disappear quickly. The two mitochondrial derivatives differ in length and diameter. In the more posterior region, the remaining anchor-shaped mitochondrial derivative has a circular crystalline region, differing from other mecopteran species. The filiform materials are peculiar and lie beside the nucleus and in the flagellum region. Sperm ultrastructural comparison of P. kuandianensis with other families supports a close affinity of Panorpodidae with Panorpidae. In addition, the occurrence of the nine accessory microtubules in the sperm axoneme of Panorpodes indicates that the 9 + 9 + 2 axonemal pattern might be a symplesiomorphy of the Mecoptera.

show abstract

The sperm structure of Embioptera (Insecta) and phylogenetic considerations

Cited by 15 publications

References 14 publications

The evolution of insect sperm − an unusual character system in a megadiverse group

The evolution of insect sperm − an unusual character system in a megadiverse group

Three-dimensional reconstruction on cell level: case study elucidates the ultrastructure of the spinning apparatus of Embia sp. (Insecta: Embioptera)

Sperm ultrastructure of Panorpodes kuandianensis (Mecoptera: Panorpodidae)

Contact Info

Product

Resources

About