Craticula scientiacivica (Stauroneidaceae), sp. nov., a new diatom species found during a citizen science project

Craticula scientiacivica Moyón & S. Blanco, sp. nov., is a new diatom species discovered during the CiDIA-micro citizen science project at the University of León, Spain, which evaluates the environmental impact of biodegradable packaging on periphytic diatom communities. This initiative involved secondary school students and teachers in sampling experimental aquaria inoculated with natural benthic algae from Laguna Sentiz (León, Spain), revealing the novel taxon in a control treatment under alkaline conditions (pH 9, low nutrients).

Valves are linear-lanceolate, panduriform, with concave margins and protracted rostrate apices, measuring 32.0–35.7 μm long and 3.9–6.3 μm wide. Striae are uniseriate, 18–19 in 10 μm, and weakly radiate, with circular central areolae (37–46 in 10 μm) transitioning to elliptical forms apically. The raphe is filiform, with expanded, unilaterally deflected proximal endings and terminal hooks extending onto the mantle.

Teratological forms were found in 26 % of individuals, featuring deformed outlines, misaligned raphe, and aberrant copulae, possibly linked to culture conditions despite the absence of chemical stressors. Morphologically, C. scientiacivica aligns with Craticula (Stauroneidaceae) via its shallow mantle, apically elongated external foramina, and deflected central raphe endings, but its unique panduriform shape and dimensions distinguish it from congeners.

Molecular data are pending, but its occurrence in a single experimental tank suggests aerial propagule dispersal. This discovery underscores the role of citizen science in uncovering hidden biodiversity, bridging education and taxonomy in diatom research.