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Advances in the Knowledge of the Reproductive Processes of the Critically Endangered Pinna nobilis Linnaeus, 1758
by
, , , and
Emilio Cortés Melendreras
1
,
Pilar Martínez-Martínez
2,3,*,
Juan Vera Inglés
1,
Miguel Ángel Sánchez
1,
Antonio Crespo Montalt
1,
Yolanda Fernández-Torquemada
2,3
,
Ezequiel Martínez Ortega
1
and
Francisca Giménez Casalduero
2,3 1
Aquarium of the University of Murcia, University of Murcia, 30002 Murcia, Spain
2
Department of Marine Sciences and Applied Biology, University of Alicante, 03690 San Vicente del Raspeig, Spain
3
Marine Research Centre of Santa Pola, University of Alicante, 03130 Santa Pola, Spain
*
Author to whom correspondence should be addressed.
Biology 2026, 15(11), 847; https://doi.org/10.3390/biology15110847 (registering DOI)
Submission received: 29 April 2026
/
Revised: 22 May 2026
/
Accepted: 27 May 2026
/
Published: 28 May 2026
Simple Summary
The fan mussel (Pinna nobilis) is a critically endangered bivalve species found in the Mediterranean Sea. Urgent action is needed to ensure its survival. This study focused on the remaining population in Spain’s Mar Menor lagoon. First, the species’ natural reproductive period in the lagoon was identified. Then, this information was used to carry out breeding experiments in a laboratory setting that replicated these conditions. Several successful spawning events were achieved. The study revealed that individuals mature gametes simultaneously but release male and female gametes at different times, which may help avoid self-fertilization. Very high fertilization rates were observed, suggesting that fertilization occurs internally, which improves our understanding of how this species reproduces. These results provide valuable insights for future conservation and breeding programs aimed at safeguarding the species.
Abstract
As part of conservation efforts for Pinna nobilis, a critically endangered bivalve endemic to the Mediterranean Sea, laboratory programs have been developed to maintain and breed specimens. However, progress in the ex situ conservation of the species remains limited and challenging. This study aims to advance the knowledge required to establish effective reproductive protocols for P. nobilis, specifically focusing on the population in the Mar Menor lagoon, one of the last two surviving populations along the Spanish coast. The first phase of this study involved characterizing the reproductive events in the lagoon. Subsequently, two ex situ reproduction experiments were conducted under conditions designed to replicate the lagoon’s natural environment. Three reproductive events were detected in the lagoon between 2019 and 2022, and five successful spawning events occurred across the two ex situ experiments. The conditions for maintenance, maturation, and induction of the individuals are described. In all cases, the percentage of fertilized oocytes released was remarkably high, suggesting internal fertilization, but not self-fertilization, within the pallial cavity. Additionally, ex situ individuals exhibited simultaneous hermaphroditism, with synchronous maturation and alternating release of gametes, effectively preventing self-fertilization. These findings represent a significant step forward in understanding the reproductive biology of P. nobilis and contribute to efforts aimed at ensuring the species’ long-term survival.
