A Survey Study of the Freshwater Leech Fauna (Hirudinea) in Springs and Water Pools of the Jabal Al-Akhdar Region, Libya

Abstract

This study aimed to survey and document the diversity of freshwater leech fauna (Hirudinea) at ten water bodies (springs and pools) in the Jabal Al-Akhdar region of northeastern Libya, through monthly field visits to each site over twelve consecutive months, from November 2024 to October 2025. The species was not recorded at any of the ten sites during eight months of the study (November–April and September–October), while it was detected at all ten sites during the four months from May to August, with a 100% detection rate (not relative abundance) each month. A cumulative total of 100 specimens (10 per site) were collected during the months of occurrence; based on morphological examination alone without molecular confirmation specimens were identified as most likely belonging to a single species, the Nile leech Limnatis nilotica (Savigny, 1822). This identification relied on external morphological characters using internationally recognised taxonomic keys, as molecular analysis was not available. The results indicate limited recorded leech diversity in the region compared with Tunisia and Morocco; several possible ecological and geographical explanations are proposed and warrant further investigation, while acknowledging that reliance on morphology alone constitutes a methodological limitation in light of recent molecular studies revealing the possible presence of cryptic species within the genus in North Africa. The study recommends broadening the spatial coverage of sites, repeating the survey across multiple years, measuring associated environmental variables, and applying DNA barcoding techniques to confirm the specific identity of the specimens.