New record of Nausithoe werneri (Scyphozoa, Coronatae, Nausithoidae) from the Brazilian coast and a new synonymy for Nausithoe maculata

Abstract

The order Coronatae (Scyphozoa) includes six families, of which Nausithoidae Haeckel, 1880 is the most diverse with 26 species. Along the Brazilian coast, three species of the genus Nausithoe Kölliker, 1853 have been recorded: Nausithoe atlantica Broch, 1914, Nausithoe punctata Kölliker, 1853, and Nausithoe aurea Silveira & Morandini, 1997. Living polyps (n = 9) of an unidentified nausithoid were collected in September 2002 off Arraial do Cabo (Rio de Janeiro, southeastern Brazil) at a depth of 227 m, and have been kept in culture since then. We compared these specimens with three species cultured in our laboratory: Nausithoe aurea (from Ilhabela, São Paulo, Brazil), Nausithoe maculata Jarms, 1990 (from Cuba and Puerto Rico), and Nausithoe werneri Jarms, 1990 (from the Atlantic Ocean off Morocco and from the Mediterranean Sea). The criteria used for comparison were: main aspects of the morphology, life cycle, and DNA sequences (18S, 28S, and COI). The results indicate that the unidentified polyps belong to N. werneri. Furthermore, N. aurea is considered a junior synonym of N. maculata.

Keywords: Coronamedusae; jellyfish; life cycle; periderm; polyp; scyphomedusae; systematics.

Figure 1.

Nausithoe sp. from Brazil. A tissue balls originated from polyp AC02 ephyrae B emerged polyps from same tissue balls in A after 22 weeks, showing the polyp opening; note that the basal parts are fused C external view of part of polyp AC18, showing by transparency the internal whorls of cusps (wc) D oral disc of polyp AC01, showing the tentacle crown (tc) and the mouth opening (m) with the gastric longitudinal septa (gs) E polyp AC02 releasing ephyrae.

Figure 2.

Schematic view of a typical Nausithoe sp. adult medusa, illustrating the main characters. A aboral view B lateral view. dc diameter of coronal furrow dr diameter between rhopalia dt total diameter cg coronal grove gc gastric cirri m manubrium ml marginal lappets r rhopalium t tentacle e eyespot g gonad s statolith.

Figure 3.

SEM of cross-sections of the tube of the polyp of Nausithoe sp. AC02 at different heights. A more-basal series, with 16 cusps and additional cusps over 4 larger perradial cusps B and C two more-distal series (C being the highest along the tube), each with 8 cusps.

Figure 4.

Adult medusae from polyps of Nausithoe sp. AC10 (A–C) and AC20 (D–H) A beginning of gonad (g) development B two gonads with gametic cells still differentiating C general view of a medusa that we managed to maintain until the gonads emerged (note degree of irregularities in this specimen, due to the long period in cultivation) D aboral view of 3-month-old medusa, showing the radial muscle (rm), marginal lappets (ml), rhopalium (r), and tentacles (t) E detail of 6-month-old medusa, showing gastric filaments (gf), rhopalium with ocelli (e), and statocyst (s), and coronal groove (cg); note, no trace of gonad development F, G and H Oral view of medusae, showing lips (l) and projection of the manubrium, from less projected (F) to more projected (H).

Figure 5.

Photomicrographs of the two nematocyst types found in Nausithoe sp. A three heterotrichous microbasic euryteles discharged B holotrichous isorhiza capsules of two different sizes (large, grey arrow; small, black arrow) C a small discharged holotrichous isorhiza.

Figure 6.

Aboral view of Nausithoe maculata medusae from Cuba’s polyp culture. A four-month-old medusa with mature male gonads (g), long tentacles (t), and malformations in the lappets and central disc. B three-month-old medusa with mature female gonads (g), showing the rhopalium (r), coronal groove (cg), marginal lappets (ml) with pigment spot (ps), gastric cirri (gc), and tentacles (t).

Figure 7.

Nausithoe werneri male medusae from Mediterranean’s polyp culture (A–C 5 months old D 3 months old) A aboral view of an adult medusa with mature gonads (g), contracted lappets, and extended tentacles (t) B detail of gastrovascular cavity, focusing on the gastric cirri (gc) C lateral view, focusing on the lips (l) and the extension of the manubrium D beginning of gonad (g) development (aboral view).