CARYBDEIDAE Gegenbaur, 1857

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 : 2605-2606

Family CARYBDEIDAE Gegenbaur, 1857

Only one genus............................... Genus Carybdea ( Figures 2D , 3A, C )

Carybdea Péron and Lesueur, 1809 (refer to Mayer 1910; Gershwin and Gibbons 2010; Bentlage et al. 2010 for reviews of the genus). Type species: Medusa marsupialis Linnaeus, 1758 , by subsequent designation ( Haeckel 1880). Species: C. arborifera Maas, 1897 , C. aurifera Mayer, 1900 nomen dubium, C. branchi Gershwin, 2009 , C. brevipedalia Kishinouye, 1891a , C. latigenitalia Kishinouye, 1891a nomen dubium?= C. brevipedalia , C. marsupialis (Linnaeus, 1758) , C. mora Kishinouye, 1910 = C. brevipedalia , C. morandinii Straehler-Pohl and Jarms, 2011 [only the polyp and early stages in medusa development are known ( Straehler-Pohl and Jarms 2011) and it is possible that this species does not belong to Carybdea or is synonymous with another cubozoan], C. murrayana Haeckel, 1880 , C. prototypus ( Haeckel, 1880) nomen dubium, C. rastonii Haacke, 1886 , C. verrucosa Hargitt, 1903 nomen dubium, C. xaymacana Conant, 1897 .

Geographic distribution of the family

Global; tropical to temperate; neritic.

Remarks

Carybdea represents the oldest described genus within Cubozoa and many cubozoan species had been classified in this genus before the taxonomic revisions of the last decade. The family name Carybdeidae can be traced back to its establishment as Carybdeae by Lesson (1843) (cf. Calder 2009). However, Lesson (1843) established the taxon Carybdeae for a group of species that actually did not comprise any cubozoan species while Gegenbaur (1857) revised Lesson’s (1843) taxonomic framework to establish Carybdeidae more in line with how we understand the family today (cf. Haeckel 1880). For this reason, the family name Carybdeidae and order name Carybdeida are most often attributed to Gegenbaur (1857) rather than Lesson (1843).

Among the species contained in the monogeneric family Carybdeidae , most notably Carybdea alata was reclassified as Alatina alata ( Gershwin 2005a; see above) and Carybdea sivickisi was reclassified in the Tripedaliidae as Copula sivickisi ( Bentlage et al. 2010; see below). At present Carybdeidae represents a monogeneric family containing the sole genus Carybdea . All members of this family can readily be recognized by their heart-shaped rhopaliar niche ostia (details in Gershwin and Gibbons 2009; Collins et al. 2011). Gershwin and Gibbons (2009) present a comparative overview of the species of Carybdea and the morphological characters distinguishing these species. However, some species are missing from that study (e.g. C. arborifera ).

Another species contained in Gershwin and Gibbons (2009) treatment is C. mora , which was recently considered to be the junior synonym of C. brevipedalia ( Bentlage et al. 2010) . Both species were described by Kishinouye (1891a, 1910) from Honshu, Japan. Carybdea brevipedalia was described from Shima ( Kishinouye 1891a) whereas C. mora was described from Tokyo Bay ( Kishinouye 1910) only some 200–300 km north of Shima. The descriptions of both species are lacking considerable detail and provide little to distinguish between the two species. In fact, both species seem to overlap in their morphological characteristics. In particular, the gastric phacellae consist of rows of 10–12 brush-like filaments in each corner of the stomach in C. brevipedalia ( Kishinouye 1891a) and 8–12 brush-like filaments in C. mora ( Kishinouye 1910) . We investigated several specimens of Carybdea collected from different locations in Japan and all possessed similar numbers of brush-like filaments in the corners of their stomachs and did not seem to differ in any other way. Pending further evidence, molecular and morphological, it seems most prudent to consider C. mora to be the junior synonym of C. brevipedalia (cf. Bentlage et al. 2010); the species is commonly known as Andon Kurage in Japan.

In summary, original descriptions as well as those provided by Mayer (1910) should be consulted in addition to Gershwin and Gibbons (2009) for identifying species of Carybdea . It is likely that several undescribed species of Carybdea exist, a view supported by molecular genetic evidence ( Bentlage et al. 2010). At the same time some species names may be synonymous with each other. As such, the family Carybdeidae would benefit from a comprehensive taxonomic revision combining both morphological and molecular genetic data.

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.