Gastropods (Mollusca) of the Priority Marine Region to Conserve Biodiversity No. 31 &Ldquo;Tlacoyunque”, Mexico, Associated with the Rocky Intertidal

Why It Matters

The study provides the most comprehensive baseline of intertidal gastropod biodiversity in the region, informing conservation priorities for a habitat that underpins coastal ecosystem health and fisheries productivity.

Key Takeaways

• 103 gastropod species identified across nine intertidal sites
• Inventory completeness ranged from 78% to 89%
• Five families held over half species richness
• Nine species newly recorded for Guerrero state
• H' diversity index 4.57 bits; evenness 0.684

Pulse Analysis

The rocky intertidal zone is a keystone ecosystem, offering shelter, feeding grounds and breeding sites for a multitude of marine organisms. Gastropods, as primary grazers, regulate algal growth and serve as prey for higher trophic levels, making their diversity a reliable indicator of habitat health. By cataloguing 103 species and revealing a high Shannon diversity (H′ = 4.57) alongside strong evenness (J′ = 0.684), the research underscores the ecological complexity of Mexico’s priority marine region and highlights the need for fine‑scale monitoring to detect shifts driven by climate change or human disturbance.

The findings also illuminate spatial patterns that can guide management actions. Sites with heterogeneous substrates, stable micro‑environments, and reduced wave exposure harbored the richest assemblages, suggesting that physical heterogeneity buffers against environmental stressors. Conservation planners can leverage this insight to prioritize marine protected areas (MPAs) that encompass such refugia, thereby maximizing biodiversity outcomes while supporting local fisheries that depend on healthy intertidal zones. Moreover, the discovery of nine species previously unrecorded in Guerrero expands the known biogeographic range of these mollusks, prompting revisions to regional species checklists and informing biodiversity reporting obligations under international conventions.

Looking ahead, the study sets a benchmark for longitudinal assessments of intertidal communities. Integrating molecular tools, such as DNA barcoding, could refine species identification and uncover cryptic diversity hidden within the 53 occasional species. Coupled with remote sensing of habitat heterogeneity, these approaches would enable adaptive management frameworks that respond to emerging threats like coastal development and ocean acidification. Ultimately, robust baseline data empower policymakers, scientists, and stakeholders to safeguard the intertidal biome, preserving its ecological services and cultural value for future generations.