TRIPEDALIIDAE Conant, 1897

Bentlage, Bastian & Lewis, Cheryl, 2012, An illustrated key and synopsis of the families and genera of carybdeid box jellyfishes (Cnidaria: Cubozoa: Carybdeida), with emphasis on the “ Irukandji family ” (Carukiidae), Journal of Natural History (J. Nat. Hist.) 46 (41 - 42), pp. 2595-2620 : 2607-2608

Family TRIPEDALIIDAE Conant, 1897

A single pedalium per bell corner................... Genus Copula ( Figures 2C , 3D )

Two or three pedalia per bell corner................ Genus Tripedalia ( Figure 3E, J )

Copula Bentlage et al., 2010 . Type species: Carybdea sivickisi Stiasny, 1926 , by original designation. Species: Copula sivickisi (Stiasny, 1926) .

Tripedalia Conant, 1897 . Type species: Tripedalia cystophora Conant, 1897 , by original designation. Species: Tripedalia binata Moore, 1988 ; T. cystophora Conant, 1897 .

Geographic distribution of the family

Global; tropical; neritic.

Remarks

Tripedaliidae previously comprised only one genus, Tripedalia , and was immediately recognizable because both species of Tripedalia possess more than one pedalium per corner of the swimming bell (two in T. binata and three in T. cystophora ). Bentlage et al. (2010), however, determined that Copula sivickisi (previously Carybdea sivickisi ) forms a monophyletic clade with Tripedalia and so changed the diagnosis of the family to accommodate C. sivickisi . The present diagnosis of the family pertains to characters that are mainly visible in mature specimens. Tripedaliidae , according to Bentlage et al. (2010), contains all those carybdeids that display sexual dimorphism of the gonads, produce spermatophores, and in which at least the males possess sub-gastric sacs/seminal vesicles (details in Hartwick 1991). These characters are important in the reproduction of tripedaliids. Species of Tripedaliidae engage in courtship behaviour, unusual among cnidarians, that involves coupling and the active transfer of a spermatophore from the male to the female ( Werner 1973; Hartwick 1991; Lewis and Long 2005; Lewis et al. 2008). Tripedaliids have wide geographic distributions ranging from the Indo-Pacific (e.g. Moore 1988; Hartwick 1991; Lewis et al. 2008) to the Atlantic, including the Gulf of Mexico and Caribbean (e.g. Marques et al. 1997; Migotto et al. 2002; Coates 2003; Orellana and Collins 2011). Because of the small size of these species (<1 cm to about 2 cm bell height) and their neritic habitat, it is likely that several cryptic species remain to be discovered in these genera.

Descriptions of non-Australian Carukiidae

Here we describe specimens of carukiid species that were collected from the Philippines and Japan. The following abbreviations were used throughout the descriptions. National Museum of Natural History, Smithsonian Institution, USA: USNM; Bell height in mm: BH (measured from velarial turn-over to the apex of the swimming bell); interradial bell width in mm: IRW; nematocyst capsule length: L; nematocyst capsule width: W.

Figures

Figure 2. Representative species of box jellyfish from each family of Carybdeida (A–E) and one from Chirodropida (F). Note that the chirodropid possesses multiple tentacles per pedalium (F) whereas the carybdeid species possess only a single tentacle per pedalium (A–E). (A) Tamoya ohboya (Tamoyidae; image courtesy of Tim Lowry), (B) Malo kingi (Carukiidae), (C) male and female of Copula sivickisi coupling during courtship (Tripedaliidae; image courtesy of Alvaro Migotto), (D) Carybdea branchi (Carybdeidae; image courtesy of Brent Viljoen), (E) Alatina sp. (Alatinidae), (F) Chiropsalmus quadrumanus (Chiropsalmidae).sb: swimming bell, pe: pedalium, te: tentacle.

Figure 3. Key characters for identification of the Carybdeida: (A) location of taxonomic characters (Carybdea brevipedalia; image courtesy of Alvaro Migotto), (B) T-shaped rhopaliar niche ostium; note the three scales covering the niche, thus leaving a T-shaped ostium, (C) heartshaped rhopaliar niche ostium; niche ostium with only one upper covering scale, (D) key-hole shaped rhopaliar niche ostium in Copula sivickisi, (E) frown-shaped rhopaliar niche ostium in Tripedalia, (F) frown-shaped rhopaliar niche ostium in Tamoya, (G) frown-shaped rhopaliar niche ostium with rhopaliar horns in Malo, (H, I) vertical gastric phacellae in the stomach of Tamoya, (J) multiple pedalia on each corner of the swimming bell in Tripedalia, (K) crescentric gastric phacellae in Alatina (apical view). cs: covering scale, ma: manubrium, ph: gastric phacellae (comprises gastric cirri) in the stomach cavity, pc: pedalial canal, pcb: pedalial canal bend, pe: pedalium, rh: rhopalium, rn: rhopaliar niche that opens on the exumbrellar side of the bell with the rhopaliar niche ostium, rno: rhopaliar niche ostium, rho: rhopaliar horn, sto: stomach, te: tentacle, ve: velarium, vec: velarial canal.