Chrysaora colorata ( Russell, 1964 )

Morandini, André C. & Marques, Antonio C., 2010, Revision of the genus Chrysaora Péron & Lesueur, 1810 (Cnidaria: Scyphozoa) 2464, Zootaxa 2464, pp. 1-97 : 16-19

Chrysaora colorata ( Russell, 1964)

( Figures 13 –18, 74, 86)

Pelagia colorata Russell 1964: 135–136 (original description) [coast of California – USA]. Russell 1970: 87 (mention). Alvariño, 1980: 153 (mention, Tab. 1). Larson 1990: 549 (mention, tab. 1), 553 (occurrence, life cycle, suggests change of genus), fig. 1C (medusa) [southern California – USA]. Cairns et al. 1991: 12 (list), 57 (index). Fautin & Lowenstein 1992: 13–14 (proteins). Sommer 1992: 363–364 (cultivation details). Sommer 1993: 250, 253 (cultivation details), 252 (feeding). Thuesen & Childress 1994: 88 (enzyme activity), 91 (tab. 2). Lange & Kaiser 1995: 62– 63 (cultivation methods). Arai 1997: 120–121 (metabolism), 139–140 (proteins), 225 (classification). Wrobel & Mills 1998: 21 (photo), 23 (photo), 54 (description) 96, 99, 103 (mention). Gershwin 1999: 995 (ephyrae variation). Raskoff, Sommer, Hamner & Cross 2003: 74 (tab. 1, cultivation details).

Pelagia panopyra: Fewkes 1889: 26–28 (description), Pl. V (medusa) [California – USA]. Larson 1990: 553 (mention, = P. colorata ) [non Pelagia panopyra Péron & Lesueur, 1810 ].

? Pelagia sp. : Galigher 1925: 96 (occurrence of ephyrae) [Monterey Bay, California – USA].

Pelagia noctiluca panopyra: Fox & Millott 1954: 392–408 (pigments) [non Pelagia noctiluca (Forskål, 1775) ].

Pelagia cyanella: Hartman & Emery 1956: 307 (mention). Larson 1990: 553 (mention, = P. colorata ) [non Pelagia cyanella Péron & Lesueur, 1810 ].

Chrysaora colorata: Collins 2002: 420 (tab. 1). Gershwin & Collins 2002: 131 (mention, presence of quadralinga), 134– 139 (redescription; comb. nov.), figs 1b–c (quadralinga), fig. 3, 7 (medusa), fig. 4 (gonad), fig. 5 (strobilation), fig. 6 (ephyra) [ San Pedro, California – USA]. Widmer 2008b: 78, tab. 4 (ephyrae characters), 81 (key). Arai 2009: 243 (podocysts). Bayha & Graham 2009: 221 (molecular identification of polyps).

Holotype specimen. NHM 1963.7 .24.1 as Pelagia colorata (~ 30 cm in diameter, 19.vii.1962, preserved in 4% formaldehyde solution, La Jolla, California – USA).

Examined material. Holotype; CASIZ 111015 (~ 40 cm in diameter, 27.iii.1997, 4% formaldehyde solution, San Pedro, California – USA), CASIZ 111018 (ephyrae, laboratory culture Monterey Bay Aquarium , 4% formaldehyde solution), CASIZ 111019 (polyps, laboratory culture Monterey Bay Aquarium , 4% formaldehyde solution), CASIZ 119475 (~ 45 cm in diameter, female, 04.iv.1997, 4% formaldehyde solution, San Pedro, California – USA); USNM 54350 (~ 30 cm in diameter, 17.vi.1973, 4% formaldehyde solution, Mission Bay , San Diego , California – USA), USNM 54561 (~ 16 cm in diameter, vi.1975, 4% formaldehyde solution, Newport Harbour , California – USA), USNM 54562 (~ 14 cm in diameter, vi.1975, 4% formaldehyde solution, Newport Harbour, California – USA), USNM 58422 (~ 28 cm in diameter, 06.vii.1977, 4% formaldehyde solution, Huntington Beach, California – USA).

Type locality. La Jolla, southern California – USA.

Distribution. Northeastern Pacific (California – USA) ( Fig. 74).

Diagnosis. Medusae large, up to 100 cm in bell diameter; marginal lappets (in adults) squared, 4 per octant, with small canals (projections of the gastrovascular system); tentacles 8, 1 per octant; quadralinga present, with 1 or 3 lobes; colouration (adults) whitish-silvery with 16 purple-brownish stripes radiating from an apical ring.

Holotype specimen description. Specimen poorly preserved, with only a large transparent piece of mesoglea remaining. Description presented here largely complemented with Russell’s (1964) data. Umbrella diameter ~ 40 cm, hemispherical. Exumbrellar surface finely granulated (papillae); magenta, brown and blue, apical ring with 16 radiating stripes. Mesoglea thick. Marginal lappets squared, with rounded corners, with shallow median notches, 2 per octant (see comments below), purple tinged with brown. Rhopalia 8. Tentacles 8. Musculature not described. Pillars evident, thick. Oral arms long, with fringed lips. Gonads 4, interradial, folds hanging down from subgenital ostia.

Description of other specimens and additional data. Medusa: medusae up to 1 m in diameter ( Fig. 13); umbrella hemispherical, flatter in younger specimens. Exumbrella finely granulated (small papillae); whitish to silvery colouration with 16 purple radial stripes arising from apical ring ( Figs 13 –14). Mesoglea rigid, thicker centrally (~ 2 cm). Marginal lappets (in adults) squared with rounded margins, 4 per octant, with canals of gastrovascular system; all lappets of similar size; margin of rhopalar lappets overlapping (“closed rhopalium” condition); rounded in younger specimens (~ 7 cm in diameter) but already with some canals. Rhopalia 8, without ocelli, in deep clefts; exumbrellar sensory pit deep. Tentacles 8 (adults) (Fig. 15), 1 per octant; thick, 2–3 times longer than umbrellar diameter; reddish, purplish or transparent. Radial and circular musculature not discernible. Brachial disc circular, grooved in larger specimens. Pillars evident. Quadralinga present, with 1 or 3 lobes (Fig. 16). Subgenital ostia rounded, 1/5–1/8 of umbrellar diameter. Oral arms up to 6 m in length, V-shaped, with frilled free edges, distal portion distinctly spirally coiled. Central stomach circular; margin limited by insertion of radial septa. Stomach pouches 16, uniform in width at basal part; tentacular pouches enlarged at 1/5 distal part. Radial septa thin; rounded at base; straight up to ¼ of margin, then making an “S” (first thinning tentacular pouch, then enlarging it); ending near tentacular base at rhopalar lappet. Gastric filaments in 4 interradial fields. Gonads encircling gastric filaments, forming a semi-circular ring, heavily folded. Planula: no available data. Scyphistoma (Fig. 17): conical to goblet-shaped, 2–5 mm in height; oral disc 1.5–2 mm wide; typically with 16 tentacles (spiraled), length 3 times polyp height; cruciform or amorphous mouth, with prominent lips elevated in relation to oral disc; gastric septa 4; whitish. Podocysts: trapezoid, 0.2–0.5 mm wide; greenish-yellow. Strobila: polydisc (up to 56 ephyrae), purple, strobilation lasts almost 15 days. Ephyra (Fig. 18): typically with 8 arms (lobes); marginal lappets 16, pointed; rhopalia 8, with white concretions; 2–3 mm in diameter after release; purple; with a nematocyst concentration on each side of the rhopalia (on the lappets). Cnidome ( Fig. 86): Specimen USNM 54561, medusa tentacles with large holotrichous O-isorhizas [n=10; 17.6–19.6 x 11.7–14.7 µm (mean = 18.23 x 14.41 µm)]; small holotrichous aisorhizas [n=10; 4.9–6.8 x 2.9–3.9 µm (mean = 6.07 x 3.13 µm)]; holotrichous A-isorhiza [n=10; 8.8–10.7 x 4.9–5.8 µm (mean = 9.80 x 5.68 µm)]; heterotrichous microbasic rhopaloids [n=10; 8.8–12.7 x 3.9–6.8 µm (mean = 10.68 x 5.48 µm)].

Systematic remarks. Chrysaora colorata is unique in having only 1 tentacle per octant (totaling 8) and possessing quadralinga ( Wrobel & Mills 1998; Gershwin & Collins 2002). The species was first referred to the genus Pelagia due to the presence of only 8 tentacles ( Russell 1964; Larson 1990). Gershwin & Collins (2002) assigned the species to the genus Chrysaora given life cycle and morphological characters, and based on a phylogenetic hypothesis. The quadralinga description is said to be trilobed, but some specimens (USNM 54562, 58422) have only one lobe. The original description ( Russell 1964) mentions only 2 lappets per octant, but in fact they must be counted as 4 with thin membranes in between.

Biological data. The species is on exhibit in some public aquaria in the USA; but no detailed data are available on its development. The first mention of the life cycle was an abstract by Sommer (1988); later Gershwin & Collins (2002) described in detail the polyp and ephyra stages.

Etymology. colorata : due to characteristic colouration, derived from the Greek coloratus (= coloured) ( Brown 1956; Russell 1964).