An annotated and illustrated identification guide to common mesophotic reef sponges (Porifera, Demospongiae, Hexactinellida, and Homoscleromorpha) inhabiting Flower Garden Banks National Marine Sanctuary and vicinities Author Diaz, Maria Cristina https://orcid.org/0000-0001-9485-0011 Harbor Branch Oceanographic Institute, Florida Atlantic University, Fort Pierce, FL, USA taxochica@gmail.com Author Nuttall, Marissa https://orcid.org/0000-0003-1384-8978 Flower Garden Banks National Marine Sanctuary, Galveston, TX, USA & CPC Inc, Galveston, TX, USA Author Pomponi, Shirley A. https://orcid.org/0000-0003-4982-1515 Harbor Branch Oceanographic Institute, Florida Atlantic University, Fort Pierce, FL, USA Author Ruetzler, Klaus National Museum of Natural History, Smithsonian Institution, Washington D. C., USA Author Klontz, Sarah Genetic Disease Research Branch, NHGRI, NIH, Bethesda, MD, USA Author Adams, Christi https://orcid.org/0000-0002-8411-4595 Flower Garden Banks National Marine Sanctuary, Galveston, TX, USA Author Hickerson, Emma L. https://orcid.org/0000-0002-2595-8878 Flower Garden Banks National Marine Sanctuary, Galveston, TX, USA Author Schmahl, G. P. https://orcid.org/0000-0002-5657-5204 Flower Garden Banks National Marine Sanctuary, Galveston, TX, USA text ZooKeys 2023 2023-05-11 1161 1 68 http://dx.doi.org/10.3897/zookeys.1161.93754 journal article http://dx.doi.org/10.3897/zookeys.1161.93754 1313-2970-1161-1 4CE0D6C5C3044F748387FCC71F8F8AC0 97BBCF0865EA537F8147171EA5BBA1B5 Batzella cf. rubra (Alcolado, 1984) Fig. 31 Diagnostic features. Thinly encrusting sponge (1-10 mm thick) growing over dead coral. Orange to red color in life, black to purple in alcohol. The surface is smooth to bumpy with whitish branching dermal canals, and roundish papillae with two or three clumps of ostia. The cf. is due to the rounded papillae only described for Batzella mollis , a species found at the "Juan Fernandez and Desventuradas islands" off the Chilean Pacific coast. Figure 31. Batzella cf. rubra , 70 m deep. Sample DFH9-6F. Similar species. Esteves et al. (2018) describe three tropical western Atlantic Batzella spp: Batzella rubra (deep orange-red, smooth), Batzella ficus (dark brown), and Batzella cataniresis (yellow). Monanchora arbuscula in its orange morphotype can be confused with Batzella cf. rubra . Distribution and abundance. This is the first record from mesophotic reefs. At FGBNMS the species has been recorded with rare to low abundance (1-10) in three localities. Ecology. Coralline algae reefs, algal nodules, lower mesophotic reefs. Identification. KR, SK, CA, MCD. References. Alcolado 1984 ; Esteves et al. 2018 .