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- Uncovering the shell game with barcodes: diversity of meiofaunal Caecidae snails (Truncatelloidea, Caenogastropoda) from Central AmericaPublication . Egger, Christina; Neusser, Timea P.; Norenburg, Jon; Leasi, Francesca; Buge, Barbara; Vannozzi, Angelo; Cunha, Regina L.; Cox, Cymon J.; Jörger, Katharina M.Caecidae is a species-rich family of microsnails with a worldwide distribution. Typical for many groups of gastropods, caecid taxonomy is largely based on overt shell characters. However, identification of species using shell characteristics is problematic due to their rather uniform, tubular shells, the presence of different growth stages, and a high degree of intraspecific variability. In the present study, a first integrative approach to caecid taxonomy is provided using light-microscopic investigation with microsculptural analyses and multi-marker barcoding, in conjunction with molecular species delineation analyses (ABGD, haplotype networks, GMYC, and bPTP). In total 132 specimens of Caecum and Meioceras collected during several sampling trips to Central America were analyzed and delineated into a minimum of 19 species to discuss putative synonyms, and supplement the original descriptions. Molecular phylogenetic analyses suggest Meioceras nitidum and M. cubitatum should be reclassified as Caecum, and the genus Meioceras might present a junior synonym of Caecum. Meiofaunal caecids morphologically resembling C. glabrum from the Northeast Atlantic are a complex of cryptic species with independent evolutionary origins, likely associated with multiple habitat shifts to the mesopsammic environment. Caecum invisibile Egger & Jörger, sp. nov. is formally described based on molecular diagnostic characters. This first integrative approach towards the taxonomy of Caecidae increases the known diversity, reveals the need for a reclassification of the genus Caecum and serves as a starting point for a barcoding library of the family, thereby enabling further reliable identifications of these taxonomically challenging microsnails in future studies.
- Reproductive phenology and sexual propagation of the pink sea fan Eunicella verrucosa (Pallas, 1766): implications for coral restorationPublication . Egger, Christina; Melo, Catarina; Marquardt, Bailey; Engelen, Aschwin; Melzer, Roland R.; Santos, Elsa; Fernandes, Margarida; Baylina, Núria; Serrao, Ester A.; Coelho, Márcio A. G.The widespread decline of coral-dominated ecosystems has highlighted the urgent need for active habitat restoration. Coral restoration using sexually produced individuals instead of clonal fragments is essential to reduce impacts on donor populations and promote genetic diversity, which is vital for adaptability to environmental changes. However, for most coral species critical knowledge of reproduction and larval ecology for ex situ sexual propagation is lacking. To address this gap, this study presents the first report of spawning of the octocoral Eunicella verrucosa in the North-East Atlantic and describes larval development and settlement. The annual reproductive timing in SouthWest Portugal was determined from samples collected as fisheries bycatch from the same habitat and monitored for comparison across distinct durations and conditions. The species exhibited split spawning (three major events approximately every two weeks) over about one month (mid-September–mid-October). Spawning patterns can suggest lunar periodicity but shifted between colonies kept in distinct conditions. Oocytes were positively buoyant and developed into swimming larvae after three days. Settlement trials using substrates such as natural rock, crustose coralline algae (CCA), and gorgonian skeleton, showed larvae started testing the substrates about two weeks after spawning, with settlement activity continuing over up to three months. Fully developed recruits were observed after one month, with sclerite production starting before tentacle development. The observation of new larval settlement up to three months indicates a prolonged competency period. This study provides crucial data for coral restoration efforts using ex-situ sexual propagation of a vulnerable species.