Carybdea branchi, Gershwin, Lisa-Ann & Gibbons, Mark J., 2009

Gershwin, Lisa-Ann & Gibbons, Mark J., 2009, Carybdea branchi, sp. nov., a new box jellyfish (Cnidaria: Cubozoa) from South Africa, Zootaxa 2088, pp. 41-50 : 42-49

Carybdea branchi , sp. nov.

Plates 1–3

Carybdea alata . – Uchida 1970: 291 –293, text fig. 2; off Cape Town. – Branch et al., 1994: 32, pl. 13.1; SW Africa. Tamoya haplonema . – Pagès et al., 1992: 57 –58, fig. 67.

Carybdea n. sp. (Cape Town) Gershwin, 2005: throughout.

Carybdea n. sp. B Gershwin, 2006: 9.

Holotype: SAMCT H4863, 18 January 2001, SE corner of Alfred Basin, in front of the Two Oceans Aquarium, V&A Waterfront, Cape Town [33˚54.527’S, 018˚25.074’E], coll. by L. Gershwin & L. Hoensen, hand-dipped from surface; 68.03 mm BH, 95.05 mm DBW, 48.22 mm IRW, 6.93 mm TBW.

Paratypes: SAMA H923 (=RVS A262), Soldhana Bay, South Africa, 28 April 1958; 32.04 mm BH, 44.27 mm DBW, 21.72 mm IRW, tentacle width 2.64 x 1.87 mm. SAMA H924 (=RVS A389F), South Africa, April 1959?; 41.70 mm BH, 50.19 mm DBW, 24.89 mm IRW, pedalium 22.03 mm TL, tentacle width 3.51 mm. SAMA H925 (=RVS A389A), same coll. data as H924; 39.86 mm BH, 43.66 mm DBW, 21.51 mm IRW. SAMA H926 (=RVS A389 H, I), same coll. data as H924; 2 specimens: A) 31.00 mm BH, 40.37 mm DBW, 20.76 mm IRW, 3.16 mm ATBW; B) 38.46 mm BH, 50.15 mm DBW, 24.06 mm IRW, 3.21 mm ATBW. SAMA H927 (=RVS A298), South Africa, Langebaan, coll. by University of Cape Town (Ecol. Survey LB.514), 28 April 1958; 41.98 mm BH, 51.25 mm DBW, 25.85 mm IRW. SAMA H928 (=RVS A389J), same coll. data as H924; 25.73 mm BH, 29.95 mm DBW, 11.91 mm IRW. SAMA H929, same data as H925; 48.00 mm BH, 51.86 mm DBW, 26.16 mm IRW, largest tentacle 6.32 x 3.65 mm diameter. SAMA H930 (=RVS A389M), South Africa, coll. by?University of Cape Town, April 1959?, immature, 17.61 mm BH, 22.25 mm DBW, 9.94 mm IRW. SAMA H931 (=RVS A389L), same coll. data as H930, immature, 22.70 mm BH, 25.92 mm DBW, 11.76 mm IRW. SAMA H932 (=RVS A389K), same coll. data as H930; immature, 20.45 mm BH, 26.00 mm DBW, 12.86 mm IRW. SAMA H933 (=RVS A390), University of Cape Town, SB 112, South Africa, 14 July 1946; immature, 16.29 mm BH, 20.33 mm DBW, 11.23 mm IRW. SAMA H934 (=RVS A376), University of Cape Town, South Africa, probably Langebaan, 20 August 1946; 3 specimens: A) 49.02 mm BH, 62.75 mm DBW, 27.57 mm IRW, 3.08 mm ATBW; B) 43.91 mm BH, 53.54 mm DBW, 24.95 mm IRW; C) 44.91 mm BH, 54.14 mm DBW, 24.04 mm IRW. SAMA H1064, same coll. data as H924; 37.36 mm BH, 46.88 mm DBW, 21.64 mm IRW. NNM 5228, Port Elisabeth, 26 May 1936; 4 specimens, 62.17 – 65.90 mm BH. NHM 2000.1800–1803, Simon’s Town Docks, False Bay, South Africa, coll. 17 November 1938 by the Discovery Expedition; 4 specimens, BH (mm): 44.50, 46.22, 47.44, 53.34. SAMCT H4860, no loc. data, coll. by G. Branch; 57.60 mm BH, 75.33 mm DBW, 36.58 mm IRW. SAMCT 4861, off Langebaan Jetty, 29 September 1959, coll. by University of Cape Town Research, by hand at surface; 37.92 mm BH, 49.82 mm DBW, 24.58 mm IRW, 3.94 mm TBW. SAMCT H4862, no loc. data, 14 April 1963, coll. by University of Cape Town Ecological Survey #CP 696A; male, 58.31 mm BH, 84.20 mm DBW, 39.49 mm IRW, 5.81 mm TBW. SAMCT H4864, same data as holotype; 2 specimens: A) 51.20 mm BH, 66.52 mm DBW, 33.17 mm IRW; B) 47.45 mm BH, 64.56 mm DBW, 32.68 mm IRW. SAMCT H4865, same data as holotype; 4 specimens: A) 37.99 mm BH, 45.65 mm DBW, 23.35 mm IRW; B) 36.99 mm BH, 47.89 mm DBW, 23.85 mm IRW; C) 41.78 mm BH, 55.62 mm DBW, 27.54 mm IRW; D) 44.57 mm BH, 55.11 mm DBW, 29.24 mm IRW. SAMCT H4866, same loc. as holotype but collected 17 January 2001, by L. Gershwin & G. Branch; 6 specimens: A) 52.83 mm BH, 70.90 mm DBW, 32.51 mm IRW; B) 47.75 mm BH, 59.46 mm DBW, 30.93 mm IRW; C) 42.64 mm BH, 54.41 mm DBW, 26.67 mm IRW; D) 44.79 mm BH, 55.09 mm DBW, 28.86 mm IRW; E) 42.24 mm BH, 53.47 mm DBW, 30.02 mm IRW; F) 33.26 mm BH, 40.43 mm DBW, 18.49 mm IRW, 27.90 mm rhopalium to apex, 2.89 mm TBW, 17.85 mm outer pedalial length. ZMUC unnumb., False Bay, coll. Papenfuss, “Africana”; 48.56mm BH.

Type locality. Albert Basin, Victoria & Albert Waterfront, Cape Town, South Africa.

Diagnosis. Carybdea with a large, robust, well sculptured body; nematocyst warts densely scattered over whole body and abaxial keels of pedalia, lacking on adaxial keels; adaxial pedalial keels broadly rounded; bend of pedalial canal with a bulge or lateral thorn; velarial canals 2 per octant, dendritic, highly diverticulated; manubrium long; phacellae greatly bushy; mesenteries well developed; brownish pigmented areas conspicuous over proximal and distal regions of pedalia, as well as over phacellae.

Description. Bell to about 68 mm in height (after several days in formalin), about 80 mm live (Plate 1A), with thick, rigid mesoglea, especially apically; with numerous oblong to amorphous small unraised or slightly raised nematocyst warts scattered densely over entire exumbrella (Plate 1B). Coronal indentation shallow just below apex (Plate 1A). Interradius thickened throughout bell height, with deep median furrow reaching all the way to pedalium. Adradial furrows strongly pronounced, deeper in lower half of bell (Plate 2A). Perradius smooth, raised, with rhopaliar niche surrounded by deep horseshoe-shaped furrow (Plate 2A).

Sensory niches 4, perradial, heart-shaped (Plate 2B), with 1 shallow covering scale above and 2 nearly imperceptible scales below; located approximately 1/6 BH from velarial turnover; lacking “rhopalial horns”. Subumbrellar rhopalial windows shallowly convex, with a small concavity marking junction with rhopalial stalk. Eyes 6 per rhopalium, 2 median lensed eyes plus 4 lateral pigmented eye spots. Rhopalial warts lacking. Statolith shape unknown.

Pedalia about 1/2 bell height (Plate 1A, B); outer keel densely covered with low nematocyst warts (Plate 2C), flared from body at junction, such that outer edge of pedalial canal is even with outer body wall, with pedalial keel projecting several mm beyond; inner keel greatly rounded, nearly hemispherical; without tentacular overhang. Pedalial canal strongly quadratic in cross section throughout length, flared slightly at tentacle insertion; outer portion of bend with broadly rounded bulge or lateral-pointing thorn.

PLATE 1. Carybdea branchi , sp. nov., holotype, live, lateral view. A. In situ. B. In laboratory. Bell height approximately 80 mm live, 68 mm preserved in 5–10% formalin.

PLATE 2. Carybdea branchi , sp. nov. A. Perradius, note heavy furrows (Paratype SAMA H926). B. Rhopaliar niche ostium, note strongly exaggerated heart-shape (Holotype SAMCT H4863). C. Pedalium, note dense scattering of nematocyst clusters on abaxial keel, absent on adaxial keel (Holotype SAMCT H4863). D. Velarium, note lateral diverticulations on canals in upper right (Paratype SAMA H923). E. Lips, note long, narrow shape (Paratype SAMA 923). Whitish crystals in images D & E are artifacts of preservative due to age.

Tentacles 4, with 1 per pedalium; base to about 6 mm thick, round or flattened somewhat in cross section, gradually tapering distally (Plate 1A); with nematocyst rings all of equal size.

Velarium narrow, lacking nematocyst warts or freckles. Velarial canals 2 per octant, dendritic (Plate 2D), with edges of branches bearing lateral lobations, non-anastomosing. Perradial lappets absent. Frenulum narrowly developed, comprising a single solid gelatinous cord-like strip of tissue, extending only about 3/4 distance to velarial margin.

PLATE 3 A. Carybdea branchi , sp. nov., phacella lifted up from stomach (Paratype SAMA A376); note a primary stalk visible at midline, and another behind it. B. Carybdea branchi , sp. nov., phacella dissected out from stomach (Paratype NNM 5228); note numerous primary stalks attached to body as a single bundle. C–F. Carybdeid phacellae forms, indicated with arrows, as viewed without dissection: epaulette-form (C, C. marsupialis ); linear horizontal (D, C. rastonii , image by I. Bennett); crescentic horizontal (E, Alatina rainensis ); linear vertical (F, Tamoya haplonema , image by A. Migotto). G. Crescentic phacella in situ with bell wall peeled away, Alatina mordens .

Stomach flat. Manubrium long, with large, narrowly rounded lips (Plate 2E) reaching to at least halfway down bell cavity in life. Mesenteries flap-like halfway to rhopalium, with cord-like extension to rhopalium. Phacellae (Plate 3A, B) greatly bushy, arising from up to about 20 closely pressed stalks in a single tight bundle; each stalk dendritically branched numerous times to endings of single or paired short, solid cirri. Gonads attached along entire length of interradial septa; narrowly leaf-shaped, typically not overlapping along the interradius in present collection, pleated or simple. Interradial septa lacking perforations.

Colour in life: slightly translucent whitish with conspicuous pigmentation comprising a single dark red blotch on abaxial corner of pedalium at base of each of the 4 tentacles (Plates 1A, B, 2C), a single small red blotch on apical portion of exumbrella above each of the four phacellae (Plate 1A), and a single faint brownish blotch at “shoulder” of each of the four pedalia (Plates 1A, 2C). Tentacles whitish to faintly pinkish (Plates 1A, 2C).

Nematocysts. As detailed in Gershwin (2005a; 2006: 9, Tab. 1), the tentacular nematocysts are of two types, namely small oval isorhizas (13.39–17.62 μm x 6.06–8.20 μm, n=15), and heterotrichous microbasic euryteles (19.33–31.12 μm x 11.98–16.39 μm, n=33). There are also two types of bell nematocysts, namely, spherical isorhizas (15.53–20.64 μm, n=40), and oval?amastigophores (15.42–16.30 μm x 9.54–11.05 μm, n=28). The nematocysts of the phacellae and manubrium were not examined.

Etymology. This species is named to honour Professor Emeritus George Branch (University of Cape Town), preeminent zoologist specialising in South African ecosystems.

Distribution. Presently known only from South Africa, from Port Elisabeth along the south coast, to Laangebaan, Soldhana Bay, on the west coast.

S tinging ability. George Branch recounted a sting event that he believed was from this species. The sting occurred around the chest, with a solid band width ca 2.5 mm. The effects were: (1) acute fire-like pain (lasting about 10 minutes), becoming progressively more tolerable as time went on; (2) cessation of heart-beat (for about 15 seconds), followed by abnormally rapid heart beats (guessing about three times the normal rate), followed by cessation of heartbeat once again, and again rapid heartbeats; after three bouts, the heart stabilized.

Whilst sting inhibitors or remedies have not been formally tested on C. branchi , prudence would suggest that this species should be treated similarly to other cubozoans until demonstrated otherwise. As such, the following first aid procedure is recommended:

Call for help if patient is in distress (ring ambulance)

Treat the patient: CPR if necessary

Treat the sting: Douse with vinegar to inhibit further envenomation, then apply ice as needed for pain

Monitor patient and seek medical attention as necessary

Phylogeny. Gershwin (2005a: figures 3.3, 3.4) found that C. branchi (as Carybdea n.sp. Cape Town) clustered with C. rastonii and C. mora as the sister group to the Australian form of C. xaymacana in both morphological and partial 18S phylogenies of many species of Cubozoa. This arrangement is surprising, given the closer general resemblance between C. xaymacana and C. branchi , compared to C. rastonii and C. branchi (see Table 1). Carybdea mora has long been considered identical to C. rastonii by most authors, but was demonstrated by Gershwin (2006) to have a distinctive cnidome. Carybdea branchi , C. mora , C. marsupialis and C. xaymacana have epaulette-like phacellae, whereas the linear horizontal phacellae in C. rastonii readily separate it from the others. Therefore, discordance exists between the historical morphological interpretation and the molecular and morphological phylogenies in the genus Carybdea . Without doubt, a more thorough phylogenetic analysis of more species and more specimens in the genus will help clarify these questions.

Systematic remarks. Carybdea branchi is distinguished from all other species of Carybdea in having a much larger and more robust body, and lateral digitations on the velarial canals. Of the species currently or recently recognised in the genus, Carybdea branchi is most similar to C. marsupialis , C. mora , C. murrayana , and C. xaymacana based on the shared characters of heart-shaped rhopaliar niches and tightly-clustered, epaulette-like phacellae in each corner of the stomach. However, all five species are easily separated from one another on the number and form of their velarial canals, which are only two per octant and highly dendritic in C. branchi and C. mora (the former bearing diverticulations), simpler and numbering 3–4 per octant in C. marsupialis , six per octant in C. murrayana , and only two per octant, but of two types in C. xaymacana . Furthermore, in both C. mora and C. branchi the bell is evenly scattered with conspicuous nematocyst warts, rather than having them concentrated on the interradii as in other species; however, in C. mora the warts are in very small clusters compared to those of C. branchi . Carybdea murrayana appears to lack exumbrellar nematocysts. A comparison of primary diagnostic characters is presented in Table 1.

TABLE 1. Comparison of primary diagnostic characters in the genus Carybdea . Data from original descriptions, examination of type material or new material from type locality where possible, and Gershwin (2005a; 2006b). Carybdea alata euryteles, isorhizas tall, narrow, flimsy body, very wide pedalial wings; lacking perradial

Reynaud, 1830 mesenteries

= Alatina spp.

Carybdea sivickisi football-shaped & round adhesive pads on exumbrella apex; single row of nematocyst bars on

Stiasny, 1926 euryteles, large and small ovoid outer pedalial keel; narrow pedalia isorhizas

Carybdea rastonii football-shaped euryteles and single row of nematocyst freckles on outer pedalial

Haacke, 1886 small ovoid isorhizas wing; pedalia scalpel-shaped

Carybdea mora oval microbasic euryteles and very warty exumbrella with tiny clusters; tentacles “segmented”

Kishinouye, 1910 egg-shaped isorhizas

Carybdea marsupialis microbasic euryteles, and two single row of nematocyst freckles on outer pedalial wing; pedalia

( Linnaeus, 1758) types of isorhizas scalpel-shaped

Carybdea xaymacana large club-shaped euryteles, small single row of nematocyst freckles on outer pedalial wing; pedalia

Conant, 1897 ovoid isorhizas scalpel-shaped

Carybdea murrayana not reported broadly triangular lappets

Haeckel, 1880

Carybdea branchi , sp. large oval euryteles and small very warty exumbrella and outer pedalial wings; mesenteries flap-like

nov. oval isorhizas halfway to rhopalium; brownish colouration at “shoulders” of pedalia

and over phacellae

Whilst Uchida (1970) apparently confused C. branchi for Alatina alata (as Carybdea ), the former is quite distinctive from the latter. For example, the rhopaliar niche ostia of Alatina are strongly T-shaped (with well developed lateral covering scales), whereas they are typically heart-shaped in C. branchi (Plate 2A; with modestly developed lateral covering scales); even in a case such as that in Plate 2B, in which the niches of C. branchi are somewhat T-shaped, the species would still be immediately distinguished on the basis of the gastric cirri. In Alatina , the cirri are very long and nestled in a parallel fashion in a crescentic row across each interradius (Plate 3G), rather than the many-rooted dendritic tuft in C. branchi . From Uchida’s (1970: 291–293) description, it seems quite likely that the specimen in question is referable to C. branchi rather than to A. alata .

As mentioned above, C. murrayana from West Africa could be superficially confused with C. branchi , because both are relatively large carybdeids from Africa, but the velarial canals quickly separate them: in C. branchi the sidewalls of the canals bear many lateral digitations, whereas these are lacking in C. murrayana . Moreover, C. murrayana has many more canals at the velarial turnover (6 per octant, versus 2) but fewer branches after (about 10 tips reaching velarial margin in C. murrayana ; but less than 10 reaching margin in C. branchi ). Mayer (1910), Bigelow (1938), and Kramp (1961) considered C. murrayana to be conspecific with C. marsupialis .

Ranson (1945) and Kramp (1955) reported C. marsupialis off North Africa and Tamoya haplonema off West Africa, respectively; it is currently unclear if these reports may be referable to C. murrayana , or even possibly to C. branchi . Although the range limits of these two species are not yet known, it seems plausible that the northern hemisphere/tropical reports of C. marsupialis and T. haplonema are not referable to the subtropical/cold temperate southern hemisphere C. branchi .

Pagès et al. (1992: 57–58) curiously reported a specimen from South Africa identified as Tamoya haplonema . We were unable to examine their figured specimen, but based on the description and illustrations, it seems apparent that they observed C. branchi . The colouration alone is quite distinctive, but perhaps this was overlooked in preservation, which bleaches the colour markings. However, they described the phacellae as being vertical, but they probably failed to appreciate how vertical the phacellae are in the true T. haplonema . In T. haplonema , the phacellae root-regions are spread out over a long, vertical region along the sides of the bag-like stomach, in a field maybe five times as high as wide, such that the cirri are not plainly visible through the top of the body (Plate 3F), but must be observed through the side wall or by dissection. In contrast, in C. branchi the phacellae root-regions are tightly clustered in small clumps in each corner of the stomach, plainly visible through the top of the bell without dissection. Carybdeid phacellae take numerous forms ( Gershwin, 2005a: 43, and references therein), as illustrated in Plate 3: linear horizontal (e.g., C. rastonii ), linear vertical (e.g., Tamoya haplonema ), crescentic horizontal (e.g., Alatina spp.), epaulette (e.g., C. branchi , C. marsupialis , C. mora , C. xaymacana ), and lacking ( Carukia spp., Malo spp., Morbakka , Gerongia ). Carybdea branchi also differs from Tamoya in numerous other structural characters, for example, the latter has frown-shaped rhopalial niche ostia, whereas in the former they are heart-shaped.