The Punta de la Mona Rhodolith Bed: Shallow-Water Mediterranean Rhodoliths (Almuñecar, Granada, Southern Spain)

Shallow-water rhodolith beds are rare in the Mediterranean Sea and generally poorly known. The Punta de la Mona bed extends for 16,000 square meters shallow oligotrophic waters at southern coast of Spain, off Almuñecar Alborán Sea. We present a detailed analysis structure (rhodolith cover density, size shape, sediment granulometry) morphospecies composition along depth gradient. A stratified sampling was carried out six depths (9, 12, 15, 18, 21, 24 m), estimating abundance; rhodoliths were collected from one 30 by cm quadrat each transect, resulting 18 samples total 656 rhodoliths. measured coralline algal components identified morphoanatomically through stereomicroscope SEM. Sediment on seafloor mainly consisted pebbles cobbles; highest occurred between 15 m, lowest shallowest deepest transects (9 m). Mean Rhodolith similar throughout range (23–35 mm) with slight increase although largest 21 m. In monospecific rhodoliths, depended more forming species than depth. found 25 non-geniculate morphospecies, nearly all rhodolith-forming reported recent accounts. richness (18–19) proportional abundance intermediate (15–18 where is also highest. Lithophyllum incrustans dentatum dominated (9–12 whereas Lithothamnion valens dominant greater depths. Overall, latter most common bed. shallow-water probably diverse This highlights importance conservation this habitat and, general, emphasizes role as diversity center algae. example contradicts assumption geological literature that indicative oligophotic environments high nutrients levels.