Reevaluating Spider Nutrition: The Essential Role of Arachidonic Acid in Captivity

Spiders are among the most ecologically diverse arachnids, yet their nutritional physiology remains poorly characterized despite their importance in both natural ecosystems and experimental settings. In captivity, whether in research facilities, zoos, or private collection feeding practices are often generalized and overlook the specific metabolic demands of spider biology. This has limited our understanding of how suboptimal nutrition influences growth, reproduction, and overall health. Recent advances in arachnid physiology and lipid metabolism highlight the need to reassess current husbandry standards. Arachidonic acid (ARA), an omega-6 fatty acid and precursor to eicosanoid signaling molecules, appears to play key roles in reproduction, molting, immune function, and neural regulation. While these pathways are well described in vertebrates, their mechanisms in spiders remain insufficiently defined, underscoring a critical gap in arachnid nutritional research. This review synthesizes current knowledge on the metabolic roles, dietary sources, and physiological significance of ARA within the broader framework of spider nutrition. Essential lipids such as ARA support reproductive success, cuticular integrity, and overall metabolic resilience, whereas deficiencies may contribute to stress, impaired development, and reduced fecundity—conditions commonly seen in captive populations. To address these challenges, the article proposes integrating lipidomic profiling into nutritional assessment and husbandry planning. Such an approach can guide the development of species-appropriate diets that better reflect natural metabolic needs. By incorporating lipid-focused analyses into captive management, this framework aims to improve spider welfare, enhance research reliability, and promote more refined, evidence-based feeding strategies for diverse arachnid species.