Unveiling genital specializations in Megascolex travancorensis (Oligochaeta: Megascolecidae) through scanning electron microscopy

Authors

  • Jaya Manazhy Department of Zoology, Sree Kerala Varma College, Thrissur, University of Calicut, Kerala 680011, India. https://orcid.org/0000-0002-0974-7712
  • Sona Sajeev Department of Zoology, Sree Kerala Varma College, Thrissur, University of Calicut, Kerala 680011, India. https://orcid.org/0009-0005-7823-7168
  • Aja Manazhy Department of Zoology, Sree Krishna College, Guruvayur, University of Calicut, Kerala 680602, India. https://orcid.org/0009-0006-9887-4903
  • John Warren Reynolds Oligochaetology Laboratory, 9-1250 Weber Street East, Kitchener, ON N2A 4E1, Canada & New Brunswick Museum, 277 Douglas Street, Saint John, NB E2K lE5, Canada.
  • Santhosh Punnakattu Parambil Department of Zoology, Sree Krishna College, Guruvayur, University of Calicut, Kerala 680602, India.

DOI:

https://doi.org/10.11609/jott.9997.18.4.28696-28702

Keywords:

Clitellum, earthworms, genital papilla, penial setae, Prostatic ducts, reproduction, Seminal groove, taxonomy, Tubercula Pubertatis

Abstract

When an earthworm reaches reproductive age, its clitellum, also referred to as the genital collar, observably enlarges and becomes more glandular. Genital features in Megascolecidae, including male and female pores, papillae, grooves, and glandular thickenings, show species-specific patterns linked to reproduction, thereby serving as important characters in taxonomy and systematics. This work uses comprehensive scanning electron microscopy (SEM) images to investigate the male reproductive anatomy of Megascolex travancorensis Michaelsen, 1910. A slit-shaped male pore located on a raised genital papilla, paired prostatic ducts, a seminal groove, retracted penial setae, and eye-like genital marks on segment 18 are among the distinctive morphological features highlighted in the investigation. Fine-scale structural adaptations have been shown by SEM, which has also helped to classify accurately the genus Megascolex taxonomically and provide important information about reproductive morphology.

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Published

26-04-2026

Issue

Vol. 18 No. 4 (2026)

Section

Communications

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Copyright (c) 2026 Jaya Manazhy, Sona Sajeev, Aja Manazhy, John Warren Reynolds, Santhosh Punnakattu Parambil

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