Ovaries and germline cysts and their evolution in Dermaptera (Insecta)
We studied the ovary structure and initial stages of oogenesis in 15 representatives of several dermapteran taxa, including the epizoic Arixeniina. In all examined species, the ovaries are meroistic–polytrophic. The ovaries of the basal taxa (‘Pygidicranidae’, ‘Diplatyidae’, and Labiduridae) are com...
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Published in | Arthropod structure & development Vol. 39; no. 5; pp. 360 - 368 |
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Main Authors | , , , |
Format | Journal Article |
Language | English |
Published |
England
Elsevier Ltd
01.09.2010
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Subjects | |
Online Access | Get full text |
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Summary: | We studied the ovary structure and initial stages of oogenesis in 15 representatives of several dermapteran taxa, including the epizoic Arixeniina. In all examined species, the ovaries are meroistic–polytrophic. The ovaries of the basal taxa (‘Pygidicranidae’, ‘Diplatyidae’, and Labiduridae) are composed of elongated ovarioles, attached to short lateral oviducts. In these groups, ovarioles contain several (more than 30) ovarian follicles in a linear arrangement. In the Eudermaptera, the ovaries are composed of 1–6 (Spongiphoridae) or 20–40 (Forficulidae, Chelisochidae) short ovarioles (containing 2 ovarian follicles only) that open to strongly elongated lateral oviducts. In all investigated dermapterans, the ovarian follicles are composed of two germline cells only: an oocyte and a polyploid nurse cell that are covered by a simple follicular epithelium. Our studies indicate that despite a rather unique morphology of the ovarian follicles in the examined species, the processes leading to the formation of the oocyte and nurse cell units are significantly different in basal
versus derived taxa.
The ovaries of
Arixenia esau are composed of 3 short ovarioles attached to a strongly dilated lateral oviduct, ‘the uterus’, containing developing embryos. Histological analysis suggests that the origin of the oocyte and nurse cell units in this species follows the pattern described in eudermapterans.
The interpretation of our results in an evolutionary context supports the monophyly of the Dermaptera and Eudermaptera, and the inclusion of the Arixeniina and Hemimerina in the latter taxon. |
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Bibliography: | http://dx.doi.org/10.1016/j.asd.2010.05.004 ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 ObjectType-Article-2 ObjectType-Feature-1 |
ISSN: | 1467-8039 1873-5495 |
DOI: | 10.1016/j.asd.2010.05.004 |