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Vertebrate reproductive science and technology
RESEARCH ARTICLE

The highly divergent spermatozoon of the Palawan spiny rat, Maxomys panglima has an extremely long tail

W. G. Breed https://orcid.org/0000-0003-1739-6593 A * , C. M. Leigh B and E. J. Peirce C
+ Author Affiliations
- Author Affiliations

A School of Biological Sciences, University of Adelaide, Adelaide, SA 5005, Australia.

B Adelaide Microscopy, University of Adelaide, Adelaide, SA 5005, Australia.

C School of Biomedicine, University of Adelaide, Adelaide, SA 5005, Australia.

* Correspondence to: bill.breed@adelaide.edu.au

Handling Editor: James Cummins

Reproduction, Fertility and Development 34(6) 526-530 https://doi.org/10.1071/RD21255
Published online: 25 February 2022

© 2022 The Author(s) (or their employer(s)). Published by CSIRO Publishing

Abstract

Context: Sperm morphology varies greatly across mammalian species and this variability is especially evident in murid rodents with both sperm head shape and tail length being sexually selected traits. The Palawan spiny rat, Maxomys panglima has a longer sperm tail than that currently recorded for any other mammalian species.

Aims: The aim of the current study was to determine the sperm morphology of an individual Palawan spiny rat, M. panglima.

Methods: Light and transmission electron microscopy were carried out.

Key results: We found that the sperm tail of M. panglima has an average length of 380 μm with the midpiece being approximately 185 μm in length with comparatively small mitochondria but very large coarse fibres. Furthermore, the sperm head has a less acutely flexed apical hook than that of most other murid rodents including those of several other Maxomys species.

Conclusions: The Palawan spiny rat has a highly divergent sperm morphology with an extremely long tail. It may turn out to be an important species for testing various hypotheses of sperm form and function in mammals.

Implications: These findings suggest markedly different selective pressures may have resulted in this unique sperm morphology, the functional significance of which remains to be determined.

Keywords: eutherian mammals, mammalian species, Maxomys, midpiece structure, murid rodents, Palawan Spiny rat, sperm morphology, sperm tail length.


References

Achmadi, AS, Esselstyn, JA, Rowe, KC, Maryanto, I, and Abdullah, MT (2013). Phylogeny, diversity, and biogeography of Southeast Asian spiny rats (Maxomys). Journal of Mammalogy 94, 1412–1423.
Phylogeny, diversity, and biogeography of Southeast Asian spiny rats (Maxomys).Crossref | GoogleScholarGoogle Scholar |

Breed, WG (2004). The spermatozoon of Eurasian murine rodents: its morphological diversity and evolution. Journal of Morphology 261, 52–69.
The spermatozoon of Eurasian murine rodents: its morphological diversity and evolution.Crossref | GoogleScholarGoogle Scholar | 15164367PubMed |

Breed, WG, and Musser, GG (1991). Sulawesi and Philippine Rodents (Muridae): a survey of spermatozoal morphology and its significance for phylogenetic inference. American Museum Novitates 3003, 1–15.

Breed, WG, and Taylor, J (2000). Body mass, testes mass and sperm size in murine rodents. Journal of Mammalogy 81, 758–768.
Body mass, testes mass and sperm size in murine rodents.Crossref | GoogleScholarGoogle Scholar |

Breed, WG, and Yong, HS (1986). Sperm morphology of murid rodents from Malaysia and its possible phylogenetic significance. American Museum Novitates 2856, 1–12.

Cummins, JM, and Woodall, PF (1985). On mammalian sperm dimensions. Journal of Reproduction & Fertility 75, 153–175.
On mammalian sperm dimensions.Crossref | GoogleScholarGoogle Scholar |

Ding, X, Leigh, CM, Goodman, SM, Bedford, JM, Carleton, MD, and Breed, WG (2010). Sperm morphology in the Malagasy rodents (Muroidea: Nesomyinae). Journal of Morphology 271, 1493–1500.
Sperm morphology in the Malagasy rodents (Muroidea: Nesomyinae).Crossref | GoogleScholarGoogle Scholar | 20927800PubMed |

Gage, MJG (1998). Mammalian sperm morphometry. Proceedings of the Royal Society of London Series B: Biological Sciences 265, 97–103.
Mammalian sperm morphometry.Crossref | GoogleScholarGoogle Scholar |

Gomendio, M, and Roldan, ERS (1991). Sperm competition influences sperm size in mammals. Proceedings of the Royal Society of London Series B: Biological Sciences 243, 181–185.
Sperm competition influences sperm size in mammals.Crossref | GoogleScholarGoogle Scholar | 1675796PubMed |

Gomendio, M, and Roldan, ERS (2008). Implications of diversity in sperm size and function for sperm competition and fertility. The International Journal of Developmental Biology 52, 439–447.
Implications of diversity in sperm size and function for sperm competition and fertility.Crossref | GoogleScholarGoogle Scholar | 18649256PubMed |

Gómez Montoto, L, Varea Sánchez, M, Tourmente, M, Martin-Coello, J, Luque-Larena, JJ, Gomendio, M, and Roldan, ERS (2011). Sperm competition differentially affects swimming velocity and size of spermatozoa from closely related muroid rodents: head first. Reproduction 142, 819–830.
Sperm competition differentially affects swimming velocity and size of spermatozoa from closely related muroid rodents: head first.Crossref | GoogleScholarGoogle Scholar | 21954130PubMed |

Heaney, LR, Balete, DS, Richart, EA, Veluz, MJ, and Jansa, SA (2009). Chapter 7. A new genus and species of small “tree–mouse” (Rodentia: Muridae) related to the giant cloud rats. Bulletin of the American Museum of Natural History 331, 205–229.
Chapter 7. A new genus and species of small “tree–mouse” (Rodentia: Muridae) related to the giant cloud rats.Crossref | GoogleScholarGoogle Scholar |

Humphries, S, Evans, JP, and Simmons, LW (2008). Sperm competition: linking form to function. BMC Evolutionary Biology 8, 319.
Sperm competition: linking form to function.Crossref | GoogleScholarGoogle Scholar | 19032741PubMed |

Immler, S, Moore, HDM, Breed, WG, and Birkhead, TR (2007). By hook or by crook? Morphometry, competition and cooperation in rodent sperm. PLoS ONE 2, e170.
By hook or by crook? Morphometry, competition and cooperation in rodent sperm.Crossref | GoogleScholarGoogle Scholar | 17245446PubMed |

Jansa, SA, Barker, FK, and Heaney, LR (2006). The pattern and timing of diversification of Philippine endemic rodents: evidence from mitochondrial and nuclear gene sequences. Systematic Biology 55, 73–88.
The pattern and timing of diversification of Philippine endemic rodents: evidence from mitochondrial and nuclear gene sequences.Crossref | GoogleScholarGoogle Scholar | 16507525PubMed |

McLennan, HJ, Lüpold, S, Smissen, P, Rowe, KC, and Breed, WG (2017). Greater sperm complexity in the Australasian old endemic rodents (Tribe: Hydromyini) is associated with increased levels of inter-male sperm competition. Reproduction, Fertility and Development 29, 921–930.
Greater sperm complexity in the Australasian old endemic rodents (Tribe: Hydromyini) is associated with increased levels of inter-male sperm competition.Crossref | GoogleScholarGoogle Scholar |

Pahl, T, McLennan, HJ, Wang, Y, Achmadi, AS, Rowe, KC, Aplin, K, and Breed, WG (2018). Sperm morphology of the Rattini – are the interspecific differences due to variation in intensity of intermale sperm competition? Reproduction, Fertility and Development 30, 1434–1442.
Sperm morphology of the Rattini – are the interspecific differences due to variation in intensity of intermale sperm competition?Crossref | GoogleScholarGoogle Scholar |

Pitnick S, Hoskin DJ, Birkhead TR (2009) Sperm morphological diversity. In ‘Sperm biology: an evolutionary perspective’. (Eds TR Birkhead, DJ Hosken, S Pitnick) pp. 69–149. (Academic Press: Amsterdam)

Pizzari T, Parker GA (2009) Sperm competition and sperm phenotype. In ‘Sperm biology: an evolutionary perspective’. (Eds TR Birkhead, DJ Hosken, S Pitnick) pp. 207–245. (Academic Press: Amsterdam)

Roldan, ERS, Gomendio, M, and Vitullo, AD (1992). The evolution of eutherian spermatozoa and underlying selective forces: female selection and sperm competition. Biological Reviews 67, 551–593.
The evolution of eutherian spermatozoa and underlying selective forces: female selection and sperm competition.Crossref | GoogleScholarGoogle Scholar |

Šandera, M, Andrlíková, P, Frolíková, M, and Stopka, P (2011). Changes in the curvature of sperm head apical hooks in murine rodents. Biologia 66, 916–921.
Changes in the curvature of sperm head apical hooks in murine rodents.Crossref | GoogleScholarGoogle Scholar |

Simmons, LW, and Fitzpatrick, JL (2012). Sperm wars and the evolution of male fertility. Reproduction 144, 519–534.
Sperm wars and the evolution of male fertility.Crossref | GoogleScholarGoogle Scholar | 22984191PubMed |

Taggart DA, Breed WG, Temple-Smith PD, Purvis A, Shimmin GA (1998) Reproduction, mating strategies and sperm competition in marsupials and monotremes. In ‘Sperm competition and sexual selection’. (Eds TR Birkhead, AP Møller) pp. 623–666. (Academic Press: San Diego)

Tourmente, M, Gomendio, M, and Roldan, ERS (2011). Sperm competition and the evolution of sperm design in mammals. BMC Evolutionary Biology 11, 12.
Sperm competition and the evolution of sperm design in mammals.Crossref | GoogleScholarGoogle Scholar | 21232104PubMed |

Tourmente, M, Zarka-Trigo, D, and Roldan, ERS (2016). Is the hook of muroid rodent’s sperm related to sperm train formation? Journal of Evolutionary Biology 29, 1168–1177.
Is the hook of muroid rodent’s sperm related to sperm train formation?Crossref | GoogleScholarGoogle Scholar | 26969911PubMed |