A morphological review of the jellyfish genus Nausithoe Kölliker, 1853 (Nausithoideae, Coronatae, Scyphozoa, Cnidaria) Author Molinari, Clarissa G. Departamento de Zoologia, Instituto Biociências, Universidade de São Paulo, Rua do Matão, travessa 14, n. 101, Cidade Universitária, São Paulo, SP, 05508 - 090, Brazil & School of Environment and Science, Gold Coast Campus, Griffith University, Southport, QLD 4222, Australia Author Collins, Allen G. National Systematics Laboratory, Office of Science and Technology, NOAA National Marine Fisheries Service, MRC- 153, Washington, DC 20013 - 7012, USA & Department of Invertebrate Zoology, Smithsonian National Museum of Natural History, MRC- 163, Washington, DC 20013 - 7012, USA Author Morandini, André C. Departamento de Zoologia, Instituto Biociências, Universidade de São Paulo, Rua do Matão, travessa 14, n. 101, Cidade Universitária, São Paulo, SP, 05508 - 090, Brazil & Centro de Biologia Marinha, Universidade de São Paulo, Rodovia Manuel Hypólito do Rego km 131.5, São Sebastião, SP, 11612 - 109, Brazil text Zootaxa 2023 2023-08-21 5336 1 1 32 http://dx.doi.org/10.11646/zootaxa.5336.1.1 journal article 10.11646/zootaxa.5336.1.1 1175-5326 8268440 98F89833-1EBB-41A6-B943-2091F2296D40 Nausithoe rubra Vanhöffen, 1902 ( Fig. 14 ) Nausithoe rubra Vanh ̂ffen, 1902: 30–31, pl. I. Holotype ZMB 14808. FIGURE 14. Nausithoe rubra . A —Side view of adult medusa from the coast of California (photo: George Matsumoto © 2000 MBARI). B —Adult medusa from the coast of California (© 2013 MBARI—VARS database; identity-reference 46). C–E: AMNH 2113. C —Side view of adult medusa. D —Detail of gastrovascular cavity with gastric filaments ( gf ). E —Detail of rhopalium ( rh ), note the bulb with darker pigmentation, and marginal lappets ( ml ). F —Detail of the gonads ( g ) with triangular shape (specimen NMNH 55931). Material examined: NMNH 28128 and 28129 ( two specimens from Peru , no information on depth), NMNH 55931 ( one specimen from California , USA 1975, depth: 900m ) , AMNH 2113 ( one specimen from Tower Island , Galapagos 1925, depth: 372m ) and MBARI database (identity-reference 46, coast of California 2013, 36°39’N 122°67’W, depth: 1,210m ) . Diagnosis: medusa—hyperdome red-purple bell with blue stomach. Description: Based on original description, Bigelow (1928) , Mayer (1910) , and Kramp (1961) . Adult medusa up to 15 mm in diameter; exumbrella surface of central disc covered with nematocysts; pointed marginal lappets; tentacles and bell red-purple, stomach blue; gastric septae broadly triangular; narrow perradial gastric ostia. No information about a polyp stage. Type locality: East Atlantic ( 9°31’N 9°46’E , Benguela current, 2,000m depth ) . Distribution: possibly a worldwide species in deeper waters. Remarks: Examined specimens with brownish smooth umbrella, with narrow pointed lappets (in some specimens the marginal lappets were very damaged, making it difficult to verify their morphology). Eight rhopalia with statocyst and a darker brown bulb at the base. Triangular faint orange or dark purple gonads, pointing to the margin and containing hundreds of eggs. More than 50 gastric filaments in total, close to 12 per quadrant. Some specimens had dense, white “warts” (nematocysts?) on the exumbrellar surface. The largest animal was 20 mm in diameter and had tentacles as long as 15 mm .