Marco Anglano

Mesozooplankton were studied monthly (September 2023–August 2024, 12 months) at two coastal stations, at 35 and 90 m water depth, off Punta Blanca, SW Tenerife, Canary archipelago. Sample collection involved 250 and 500 μm bongo nets. This research focused on improving the description of plankton biodiversity and dynamics of the Canary archipelago (Macaronesia area), including its role in the transport of particulate carbon. A total of 156 taxa were identified. Copepoda dominated with 85 taxa, including 72 Calanoida species. They were numerically followed by Appendicularia, Chaetognatha, and Hydrozoa. Mesh sizes varied in collection efficiency, but with a similar pattern during the annual cycle: abundance peaks in early autumn (October–November) and late winter–spring (February–April). The 35 m depth station showed 57 to 3809 ind. m⁻³ (250 μm mesh size) and 10 to 1577 ind. m⁻³ (500 μm). The 90 m depth station showed 22 to 402 ind. m⁻³ (250 μm) and 11 to 170 ind. m⁻³ (500 μm). The present study enhances our understanding of Macaronesia’s mesozooplankton dynamics related to environmental variability, which is crucial for energy transfer assessments in pelagic food webs. It reports new species for the study area, Labidocera acutifrons (Dana, 1849–1852) and Undinula vulgaris (Dana, 1849–1852), highlighting the need for consistent zooplankton monitoring to properly inform conservation and sustainable management actions in the region.

Marine Animal Forests (MAFs) in mesophotic ecosystems in some areas are mainly defined by Antipatharia (black corals). Among them, whip black corals (or unbranched corals) have a single-stem corallum and thrive in deeper habitats with strong currents. It has been suggested that the MAFs are biodiversity hotspots and may be seen as refugia and/or feeding areas for many species. The bearded fireworm, Hermodice carunculata , an omnivorous and opportunistic feeder that exhibits scavenging behavior, has been found in association with black coral forests; however, its co-occurrence with unbranched whip corals has not been previously documented and quantified. This study reveals the presence of H. carunculata alongside Stichopathes spp. in deep-water MAFs off Punta Blanca in Southwest Tenerife (Canary Islands), with a 40% co-occurrence rate in the video ROV transects. Highest values of both species were recorded at depths between 80 and 120 m. Correlations between H. carunculata and S. gracilis (r = 0.895) and S. setacea (r = 0.715) indicate positive relationships between the ecosystem engineer and the vagile species. These findings underscore the importance of MAFs in promoting biodiversity, highlight their vulnerability in a climate change world, and call for a deeper understanding of these ecosystems to inform conservation efforts.

The Levantine Basin is the first region of the Mediterranean Sea to be impacted by climate warming and the arrival of non-indigenous species (NIS) via the Suez Canal. Although Levantine zooplankton has been studied previously, recent datasets capable of detecting the occurrence of new taxa, or shifts in community composition, especially in the easternmost part of the basin, are lacking. The present study provides updated information on zooplankton composition from Tyre (South Lebanon). In this study, the occurrence of two copepod families (Canuellidae, Longipediidae) and the first regional record of Facetotecta (Y-nauplii) are reported for the first time in the Levantine Basin. Additionally, although six Calanoida species were recorded as new to the Lebanese fauna, none can be attributed to Lessepsian NIS.