Solmaris corona (Keferstein & Ehlers)

Nagata, Renato Mitsuo, Júnior, Miodeli Nogueira & Haddad, Maria Angélica, 2014, Faunistic survey of Hydromedusae (Cnidaria, Medusozoa) from the coast of Paraná State, Southern Brazil, Zootaxa 3768 (3), pp. 291-326 : 313-315

Solmaris corona (Keferstein & Ehlers)

( Fig. 33 )

References consulted. Mayer 1910: 437, fig. 288. Russell 1953: 477–480, fig. 314. Kramp 1959: 197. Kramp 1961: 278. Correia 1983: 164, fig. 62. Bouillon 1999: 434–435, fig. 3.159. Bouillon et al. 2004: 236, fig. 147.

Material. Municipality of Pontal do Paraná, Balneário de Praia de Leste (25º44’15”S – 48º21’60”W): 01/12/ 1997 — 4 specimens; (25º48’10”S – 48º04’90”W): 01/12/1997 — 1 specimen; (25º48’10”S – 48º04’90”W): 22/12/ 1997 — 1 specimen; (25º42’65”S – 48º27’85”W): 23/01/1998 — 1 specimen; (25º42’65”S – 48º27’85”W): 20/02/ 1998 — 1 specimen; (25º44’15”S – 48º21’60”W): 31/03/1998 — 1 specimen; (25º48’10”S – 48º04’90”W): 31/03/ 1998 — 1 specimen; (25º42’65”S – 48º27’85”W): 22/04/1998 — 9 specimens; (25º46’32”S – 48º12’15”W): 27/05/ 1998 — 4 specimens; (25º48’10”S – 48º04’90”W): 27/05/1998 — 5 specimens; (25º42’65”S – 48º27’85”W): 16/07/ 1998 — 5 specimens; (25º44’15”S – 48º21’60”W): 16/07/1998 — 39 specimens; (25º48’10”S – 48º04’90”W): 16/07/ 1998 — 3 specimens; (25º42’65”S – 48º27’85”W): 20/08/1998 — 63 specimens; (25º44’15”S – 48º21’60”W): 20/08/ 1998 — 98 specimens; (25º46’32”S – 48º12’15”W): 20/08/1998 — 1 specimen; (25º48’10”S – 48º04’90”W): 02/10/ 1998 — 6 specimens; (25º50’25”S – 47º55’80”W): 02/10/1998 — 14 specimens; (25º44’15”S – 48º21’60”W): 28/10/ 1998 — 2 specimens; (25º46’32”S – 48º12’15”W): 28/10/1998 — 18 specimens; (25º48’10”S – 48º04’90”W): 28/10/ 1998 — 5 specimens; (25º50’25”S – 47º55’80”W): 28/10/1998 — 6 specimens; (25º42’65”S – 48º27’85”W): 22/01/ 1999 — 1 specimen; (25º48’10”S – 48º04’90”W): 24/03/1999 — 1 specimen.

Reference specimens deposited. MZUSP 1525, 11 specimens. Dzoo-Cn 249, 9 specimens.

World distribution. In tropical and subtropical regions of the three great oceans and the Mediterranean Sea ( Russell 1953; Bouillon 1999; Bouillon et al. 2004). On both sides of the Atlantic, from Norway to the Cape of Good Hope, South Africa ( Mayer 1910; Kramp 1959a), and with multiple records from the British Islands ( Mayer 1910; Russell 1953; Ballard & Myers 2000). In the western Atlantic, Belize ( Larson 1982).

Distribution in Brazil. From the state of Paraná to Rio Grande do Sul (Navas-Pereira 1981; Correia 1983; this study).

Description. Umbrella flattened, lens-shaped, up to 15 mm in diameter ( Bouillon 1999), reaching ~ 35 mm in living specimens ( Nogueira 2011). Diameter ranging from 0.125 mm to 2.5 mm in the specimens examined; about 90% of the individuals smaller than 1 mm in diameter. Mesoglea thicker at the top, thin at the umbrellar margin, with up to 35 marginal lappets. Each lappet up to twice as long as wide. Without otoporpae. Velum well developed, usually destroyed in fixed animals, especially the smaller ones. Stomach circular, without manubrial pouches, and covering the subumbrellar surface. Mouth simple, circular. Without peripheral canal system. Bouillon et al. (2004) described gonads forming a broad ring on the outer part of the subumbrellar manubrial wall, however we did not observe this because our specimens were juveniles. Up to 35 marginal tentacles (or more?), with solid endodermal core connected to the exumbrella just above the peronia, between marginal lobes, with a length of 1.5 to 2 times the umbrellar diameter. Most specimens examined with 8–12 marginal tentacles. 1–3, rarely 4, marginal statocysts per lobe, mounted on large cushion, with long bristles.

Systematic remarks. Seven species are currently considered valid in the genus ( Bouillon & Boero 2000; Schuchert 2013). The general aspect of Solmaris corona , S. flavescens (Kölliker) and S. leucostyla (Will) is very similar. The observation of diagnostic characters, such as gonads, statocysts and the shape of the marginal lobes, is difficult in medusae collected with plankton nets, because of the damage inherent to the collection method. Solmaris leucostyla is smaller (3–7 mm) with 1–3 statocysts and is endemic in the Mediterranean (Bouillon et al. 2004). Solmaris flavescens has 12–17 tentacles, reaching 23 mm in diameter, and marginal lappets quadrate; while young S. corona measuring only a few millimeters have 8–12 tentacles, and large specimens measuring 12–15 mm have 30–36 tentacles and the marginal lappets rectangular ( Mayer 1910; Bouillon 1999; Bouillon et al. 2004). Smaller specimens were identified by comparison with larger specimens (> 2 mm from the same sample, in which important structures such as statocysts and the insertion of the tentacles were observed). This material was also compared with large medusae (> 15 mm) from the middle and outer shelf of Santa Catarina ( Nogueira 2011). In Brazil, S. flavescens has been found in Rio Grande do Norte ( Thiel 1936 apud Vannucci 1951b). Vannucci (1957: 84) considered S. flavescens a synonym of S. leucostyla and mentioned the latter, and also S. corona in her specimens from the South Brazilian Bight. Vannucci (1963: 170) mentioned S. leucostyla as abundant in the shallow waters off São Paulo, but no reference material from these campaigns is available. The genus needs a revision.

Biological data. Large aggregations of S. corona caused losses estimated at more than 5 million British pounds for the industrial production of salmonids in the British Isles in 1997 and 2001–2002 ( Purcell et al. 2007). The medusae accumulate in the gills of fish, causing gill disorders such as bleeding and necrosis ( Purcell et al. 2007; Baxter et al. 2011). Large aggregations (max. 83 org.m -3) have been found in association with the cold waters of the South Atlantic Central Water off the states of Santa Catarina and Rio Grande do Sul (Navas-Pereira 1981; Nogueira 2011).

Figures

FIGURE 33 – 37. Solmaris corona (Keferstein & Ehlers): young medusae (33); Liriope tetraphylla (Chamisso & Eysenhardt): adult (34), and young medusae (35) a courtesy of Luis Eduardo de Mattos Pukanski; Aglaura hemistoma Péron & Lesueur: adult medusae (36) gonads attached on peduncle (37).