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The Male Genital System of Goblin Spiders: Evidence for the Monophyly of Oonopidae (Arachnida: Araneae)
No full textBurger, Matthias, Michalik, Peter (2010): The Male Genital System of Goblin Spiders: Evidence for the Monophyly of Oonopidae (Arachnida: Araneae). American Museum Novitates 3675: 1-13, DOI: 10.1206/654.1, URL: http://www.bioone.org/doi/abs/10.1206/654.
Fig. 1. Male habitus, dorsal view. A. Pimoa altioculata. B. Pimoa curvata. C. Pimoa laurae. D in Ultrastructure of the Spermatozoa in the Spider Genus Pimoa: New Evidence for the Monophyly of Pimoidae plus Linyphiidae (Arachnida: Araneae)
No full textFig. 1. Male habitus, dorsal view. A. Pimoa altioculata. B. Pimoa curvata. C. Pimoa laurae. D. Pimoa edenticulata.Published as part of Michalik, Peter & Hormiga, Gustavo, 2010, Ultrastructure of the Spermatozoa in the Spider Genus Pimoa: New Evidence for the Monophyly of Pimoidae plus Linyphiidae (Arachnida: Araneae), pp. 1-17 in American Museum Novitates 3682 on page 3, DOI: 10.1206/680.1, http://zenodo.org/record/535871
Figs. 17–18. Orchestina moaba. 17 in The Male Genital System of Goblin Spiders: Evidence for the Monophyly of Oonopidae (Arachnida: Araneae)
No full textFigs. 17–18. Orchestina moaba. 17. Horizontal section of the male opisthosoma. 18. Detail of the deferent duct showing the mature spermatozoa.Published as part of Burger, Matthias & Michalik, Peter, 2010, The Male Genital System of Goblin Spiders: Evidence for the Monophyly of Oonopidae (Arachnida: Araneae), pp. 1-13 in American Museum Novitates 3675 on page 8, DOI: 10.1206/654.1, http://zenodo.org/record/535816
First investigation of the spermatozoa of a species of the superfamily Scorpionoidea (Opistophthalmus penrithorum, Scorpionidae) with a revision of the evolutionary and phylogenetic implications of sperm structures in scorpions (Chelicerata, Scorpiones)
No full textDespite their enormous diversity, spermatozoa are only scarcely studied in arachnids. In spiders, harvestmens and mites, it has been shown that spermatozoa are a potential source of characters which can support, contradict or even resolve previous phylogenetic hypotheses. In scorpions, the spermatozoa of most superfamilies (except the taxon-rich Scorpionoidea and the obscure Chaeriloidea) are known in more or less detail revealing considerable differences, especially between buthid and non-buthid scorpions. However, this apparent diversity is based on descriptions of only 12 scorpion species. In the present study, we investigated the spermatozoa of a species of the superfamily Scorpionoidea (Opistophthalmus penrithorum, Scorpionidae) for the first time by means of light and electron microscopy. The scorpionoid spermatozoa are characterized by (1) an asymmetrical, cap-like acrosomal vacuole at the tip of the anterior pole of the nucleus, (2) a short acrosomal filament, (3) a nucleus, which is tapered anteriorly, (4) a midpiece with 5-6 mitochondria and (5) an axoneme with a 9 + 0 pattern with a helical beating movement. Moreover, we provided a detailed description regarding sperm packages, that consist of approximately 250 sperm cells bent in the midpiece region, and lack a secretion sheath. Overall, the organization and general morphology of spermatozoa of the observed species is similar to what is known for non-buthids. To evaluate the evolutionary and phylogenetic implications of our results, we performed a comparative revision of sperm morphology in scorpions for the first time and proposed potential informative characters (six for spermatozoa and six for sperm packages). We concluded so far that sperm structure in scorpions could provide new characters for future comprehensive phylogenetic studies of the order, and that they could even represent synapomorphies not only for the order but for the major scorpion clades as well. © 2009 Blackwell Verlag GmbH
Fig. 2 in Ultrastructure of the Spermatozoa in the Spider Genus Pimoa: New Evidence for the Monophyly of Pimoidae plus Linyphiidae (Arachnida: Araneae)
No full textFig. 2. Pimoa altioculata. Male reproductive system, dorsal view. The highly coiled deferent ducts were partly unraveled during dissection. The testes are densely attached to each other.Published as part of Michalik, Peter & Hormiga, Gustavo, 2010, Ultrastructure of the Spermatozoa in the Spider Genus Pimoa: New Evidence for the Monophyly of Pimoidae plus Linyphiidae (Arachnida: Araneae), pp. 1-17 in American Museum Novitates 3682 on page 5, DOI: 10.1206/680.1, http://zenodo.org/record/535871
The first fossil pycnocheiridiine pseudoscorpion (Pseudoscorpiones: Cheiridiidae Procheiridium gen. nov.) from Cretaceous Burmese amber
No full textPorta, Andrés O., Michalik, Peter, Franchi, Ezequiel, Proud, Daniel N. (2020): The first fossil pycnocheiridiine pseudoscorpion (Pseudoscorpiones: Cheiridiidae Procheiridium gen. nov.) from Cretaceous Burmese amber. Zootaxa 4801 (1): 142-150, DOI: https://doi.org/10.11646/zootaxa.4801.1.
The male genital system of goblin spiders : evidence for the monophyly of Oonopidae (Arachnida, Araneae)
No full textFigs. 9–10. Opopaea recondita. 9. Horizontal section of the male opisthosoma. 10. Detail of the testis showing the different stages of spermatogenesis. Figs. 11–12. Myrmopopaea sp. 11. Horizontal section of the male opisthosoma. 12. Detail of the testis showing the different stages of spermatogenesis.Published as part of Burger, Matthias & Michalik, Peter, 2010, The Male Genital System of Goblin Spiders: Evidence for the Monophyly of Oonopidae (Arachnida: Araneae), pp. 1-13 in American Museum Novitates 3675 on page 6, DOI: 10.1206/654.1, http://zenodo.org/record/535816
Figs. 19–20. Oonops balanus. 19 in The Male Genital System of Goblin Spiders: Evidence for the Monophyly of Oonopidae (Arachnida: Araneae)
No full textFigs. 19–20. Oonops balanus. 19. Horizontal section of the male opisthosoma. 20. Detail of the testis showing the different stages of spermatogenesis. Figs. 21–22. Stenoonops reductus. 21. Horizontal section of the male opisthosoma. 22. Detail of the testis showing the different stages of spermatogenesis.Published as part of Burger, Matthias & Michalik, Peter, 2010, The Male Genital System of Goblin Spiders: Evidence for the Monophyly of Oonopidae (Arachnida: Araneae), pp. 1-13 in American Museum Novitates 3675 on page 9, DOI: 10.1206/654.1, http://zenodo.org/record/535816
Fig. 3. A in Ultrastructure of the Spermatozoa in the Spider Genus Pimoa: New Evidence for the Monophyly of Pimoidae plus Linyphiidae (Arachnida: Araneae)
No full textFig. 3. A. Pimoa laurae. Detail of testis; arrows to junctions of the somatic cells. B–C. Pimoa altioculata. B. Detail of deferent duct. C. Detail of seminal fluid. D. Pimoa laurae. Detail of seminal fluid; arrow to lateral projection of cleistospermium. E. Pimoa curvata. Detail of seminal fluid. Abbreviations: BL, basal lamina; CS, cleistospermium; LuD, lumen of deferent duct; LuT, lumen of testis; MV, microvilli; N, nucleus; Sec, secretion; V, vesicle.Published as part of Michalik, Peter & Hormiga, Gustavo, 2010, Ultrastructure of the Spermatozoa in the Spider Genus Pimoa: New Evidence for the Monophyly of Pimoidae plus Linyphiidae (Arachnida: Araneae), pp. 1-17 in American Museum Novitates 3682 on page 6, DOI: 10.1206/680.1, http://zenodo.org/record/535871
Opopaea apicalis Simon 1893
No full textOpopaea apicalis SPERM TRANSFER FORM (fig. 25): Large sperm transfer forms (.25 Mm), composed of only a chromatin thread that is embedded in an electron-dense matrix and surrounded by a thin (, 70 nm) homogeneous secretion sheath (fig. 25A, B). Spermatozoa (fig. 25): Acrosomal complex: AV absent. AF absent. Nucleus: prcN condensed chromatin thread that is tightly screwed (fig. 25C). peN absent. NC inapplicable (due to missing AF). Axoneme: absent. NOTES ON SPERMIOGENESIS (fig. 25): The chromatin is highly condensed and appears threadlike (fig. 25 C–E). Moreover, the chromatin thread is helically contorted. Some mitochondria are visible. At the end of spermiogenesis, the manchette of microtubules, which surround the developing nucleus (fig. 25E), disintegrates.Published as part of Lipke, Elisabeth & Michalik, Peter, 2015, Evolutionary Morphology Of The Primary Male Reproductive System And Spermatozoa Of Goblin Spiders (Oonopidae; Araneae), pp. 1-72 in Bulletin of the American Museum of Natural History 2015 (396) on pages 43-45, DOI: 10.1206/906.1, http://zenodo.org/record/461226
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