Octocoral Distribution Patterns at the Equatorial Front (Tropical Eastern Pacific): Muricea and Leptogorgia

Abstract

The Equatorial Front, in the southern part of the Tropical Eastern Pacific (TEP) region, has been characterized as a hotspot of functional biodiversity due to the mixing of warm and cold waters. Nevertheless, the biogeographic patterns for some organisms, such as octocorals, remain unknown in some coastal regions. Therefore, we aimed to assess the distribution of two common octocoral genera in this area, Muricea and Leptogorgia, including 14 species based on museum specimen records, along the mainland coast of Ecuador. Statistical analyses were performed on the environmental and geographical patterns (Sea Surface Temperature (SST), bathymetry, chlorophyll (CHL-a), and Photosynthetic Active Radiation (PAR)) that influence the Equatorial Front, which is subdivided into five biogeographic regions. Our results showed two hotspots of octocoral biodiversity. The SST was found to be the main environmental factor related to octocoral distribution along the Equatorial Front. Finally, the highest abundance of Muricea over Leptogorgia suggests the former species’ higher resilience to thermal fluctuations. We discuss the possible role of substrates at suitable depths, active photosynthetic radiation, and temperature in the occurrence of octocorals in the two hotspots.

Three new species of the sea fan genus Muricea (Cnidaria, Octocorallia, Plexauridae) from the northwest region of Mexico

“…The practical purposes of these Muricea species-groups (which do not necessarily have a phylogenetic relationship) and the precise morphological descriptions of these nominal species have facilitated species identification in field ecological studies, allowing the description of new species such as the most recently described species Muricea subtilis Breedy & Guzman, 2016 ( Breedy and Guzman 2016b ). Although the dominant octocoral genera in the Eastern Tropical Pacific are Leptogorgia , Muricea , and Pacifigorgia ( Breedy and Cortés 2015 ; Abad et al 2022 ), it is still difficult to infer the gamma species richness in the Northern Mexican Pacific because several new species still await formal description. Three species of Leptogorgia were recently discovered in the Gulf of California ( Hernández et al 2021 ).…”

In vivo injection of exogenous molecules into octocorals: Application to the study of calcification

“…They include over 3500 species and represent a highly diverse and ecologically important marine fauna (McFadden et al 2022). They occur worldwide, from tropical reefs, where they are greatly resilient (Lasker et al 2020 a , b ; Abad et al 2022), to the deep sea, where they exhibit great diversity (Watling et al 2011; Carugati et al 2022). In their vast majority, they form only minute calcified structures made of calcium carbonate, the sclerites, which are present throughout the organism and earned them the generic name soft corals.…”