Ctenophora

Cast of Charniodiscus arboreus, copyright Tina Negus.

Belongs within: Animalia.
Contains: Lobata, Erniettomorpha, Rangeomorpha.

The Ctenophora, comb jellies, are a group of gelatinous marine animals characterised by bands of cilia (comb rows) running longitudinally down the body. Most ctenophores have eight such bands but early fossil members of the group possessed greater numbers.

While the majority of modern comb jellies are free-living predators, some recent authors have suggested a relationship between the modern ctenophores and the sessile Ediacaran to Lower Cambrian Rangeomorpha due to a supposed similarity between the ciliated branches of the latter and ctenophore comb rows (Shu et al. 2006). The Rangeomorpha has been treated in the past as part of a broader group of sessile Ediacaran organisms known as the Petalonamae; though listed below as a single taxon for convenience, this group is almost certainly polyphyletic and many should probably be placed elsewhere in the animal family tree.

Characters (from Miller & Harley 1996, for crown group): Biradially symmetrical; diplobastic, with gelatinous mesogloea present between epidermal and gastrodermal tissue layers; gastrovascular canal system present; nervous system in form of nerve net; colloblasts (external adhesive cells) present; meridionally arranged ciliary bands (comb rows) present.

<==Ctenophora
    |  i. s.: Bathyctena chuni (Moser 1909) HMR01
    |         Coeloplana astericola BK77
    |         Mertensia ovum B26
    |         Eoandromeda octobrachiata OX15, EL11
    |         Euplokamis dunlapae PP15
    |         Dryodora glandiformis PP15
    |--+--Beroe HMR01 [Beroida OX15, Nuda]
    |  |    |--B. abyssicola Mortensen 1927 HMR01
    |  |    |--‘Medusa’ beroe Linnaeus 1758 (n. d.) DB07
    |  |    |--B. cucumis C-SC03
    |  |    `--B. ovata LGJ03
    |  `--+--+--Xanioascus OX15
    |     |  |--Fasciculus OX15
    |     |  `--+--Ctenorhabdotus capulus OX15, CM98
    |     |     `--Scleroctenophora OX15
    |     |          |--Gemmactena Ou, Xiao et al. 2015 OX15
    |     |          |    `--*G. actinala Ou, Xiao et al. 2015 OX15
    |     |          |--Thaumactena Ou, Xiao et al. 2015 OX15
    |     |          |    `--*T. ensis Ou, Xiao et al. 2015 OX15
    |     |          |--Galeactena Ou, Xiao et al. 2015 OX15
    |     |          |    `--*G. hemispherica Ou, Xiao et al. 2015 OX15
    |     |          |--Batofasciculus Hou et al. 1999 OX15
    |     |          |    `--*B. ramificans Hou et al. 1999 OX15
    |     |          |--Maotianoascus Chen & Zhou 1997 OX15
    |     |          |    `--*M. octonarius Chen & Zhou 1997 OX15
    |     |          `--Trigoides Luo & Hu 1999 OX15
    |     |               `--*T. aclis Luo & Hu 1999 OX15
    |     `--+--+--Cestus RO69 [Cestida OX15]
    |        |  |    `--C. veneris RO69
    |        |  `--+--Thalassocalycida OX15
    |        |     `--+--Ganeshida OX15
    |        |        `--Lobata OX15
    |        `--+--Platyctenida OX15
    |           `--Cypidippida OX15
    |                |  i. s.: Haeckelia rubra H04
    |                |         Callianira bialata H04
    |                |         Tinerfe cyanea H04
    |                `--Pleurobrachiidae CC93
    |                     |--Pleurobrachia PP15
    |                     |    |--P. atlantica PP15
    |                     |    |--P. bachei PP15
    |                     |    `--P. pileus LG03
    |                     |--Hormiphora foliosa H04
    |                     |--Lampetia pancerina H04
    |                     `--Minictena Carré & Carré 1993 CC93
    |                          `--*M. luteola Carré & Carré 1993 CC93
    `--Petalonamae [Petalonamidae] G79
         |  i. s.: Arumberia Glaessner & Wade 1975 G79
         |           `--*A. banksi Glaessner & Wade 1975 G79
         |         Baikalina Sokolov 1972 G79
         |           `--*B. sessilis Sokolov 1972 G79
         |         Namalia Germs 1968 G79
         |           `--*N. villiersiensis Germs 1968 G79
         |--Erniettomorpha G79
         |--Arboreomorpha EL11
         |    |--Khatyspytia grandis EL11
         |    |--Vaizitsinia sophia EL11
         |    `--Charniodiscus Ford 1958 [incl. Arborea Glaessner & Wade 1966] G79
         |         |--*C. concentricus Ford 1958 G79
         |         |--C. arboreus G79
         |         |--C. longus EL11
         |         |--C. oppositus CM98
         |         |--C. procerus EL11
         |         `--C. spinosus EL11
         `--Rangeomorpha SCM06

*Type species of generic name indicated

REFERENCES

[BK77] Barel, C. D. N., & P. G. N. Kramers. 1977. A survey of the echinoderm associates of the north-east Atlantic area. Zoologische Verhandelingen 156: 1–159.

[B26] Bigelow, H. B. 1926. Plankton of the offshore waters of the Gulf of Maine. Bulletin of the Bureau of Fisheries 40 (2): 1–509.

[CC93] Carré, C., & D. Carré. 1993. Minictena luteola, genre et espèce nouveaux de cténophore Cydippida Méditerranéen a cinq types de colloblastes. Beaufortia 43 (10): 168–175.

[C-SC03] Cavalier-Smith, T., & E. E.-Y. Chao. 2003. Phylogeny of Choanozoa, Apusozoa, and other Protozoa and early eukaryote megaevolution. Journal of Molecular Evolution 56: 540–563.

[CM98] Conway Morris, S. 1998. The Crucible of Creation. Oxford University Press: Oxford.

[DB07] Daly, M., M. R. Brugler, P. Cartwright, A. G. Collins, M. N. Dawson, D. G. Fautin, S. C. France, C. S. McFadden, D. M. Opresko, E. Rodriguez, S. L. Romano & J. L. Stake. 2007. The phylum Cnidaria: a review of phylogenetic patterns and diversity 300 years after Linnaeus. Zootaxa 1668: 127–182.

[EL11] Erwin, D. H., M. Laflamme, S. M. Tweedt, E. A. Sperling, D. Pisani & K. J. Peterson. 2011. The Cambrian conundrum: early divergence and later ecological success in the early history of animals. Science 334: 1091–1097.

[G79] Glaessner, M. F. 1979. Precambrian. In: Robison, R. A., & C. Teichert (eds) Treatise on Invertebrate Paleontology pt A. Introduction. Fossilisation (Taphonomy), Biogeography and Biostratigraphy pp. A79–A118. The Geological Society of America, Inc.: Boulder (Colorado), and The University of Kansas: Lawrence (Kansas).

[H04] Haeckel, E. 1899–1904. Kunstformen der Natur. Bibliographisches Institut: Leipzig und Wien.

[HMR01] Harbison, G. R., G. I. Matsumoto & B. H. Robison. 2001. Lampocteis cruentiventer gen. nov., sp. nov.: a new mesopelagic lobate ctenophore, representing the type of a new family (class Tentaculata, order Lobata, family Lampoctenidae, fam. nov.) Bulletin of Marine Science 68 (2): 299–311.

[LG03] Lancelot, C., & R. Groben. 2003. Meeting report: Regional conference on the ecology and impact assessment of Phaeocystis blooms in the Eastern Channel and Southern Bight of the North Sea. Protist 154 (2): 173–176.

Miller, S. A., & J. P. Harley. 1996. Zoology 3^rd ed. Wm. C. Brown Publishers: Dubuque (Iowa).

[OX15] Ou, Q., S. Xiao, J. Han, G. Sun, F. Zhang, Z. Zhang & D. Shu. 2015. A vanished history of skeletonization in Cambrian comb jellies. Science Advances 1: e1500092.

[PP15] Pisani, D., W. Pett, M. Dohrmann, R. Feuda, O. Rota-Stabelli, H. Philippe, N. Lartillot & G. Wörheide. 2015. Genomic data do not support comb jellies as the sister group to all other animals. Proceedings of the National Academy of Sciences of the USA 112 (50): 15402–15407.

[RO69] Riedl, R., & B. Ozretic. 1969. Hydrobiology of marginal caves. Part I. General problems and introduction. Internationale Revue ges. Hydrobiol. 54 (5): 661–683.

[SCM06] Shu, D.-G., S. Conway Morris, J. Han, Y. Li, X.-L. Zhang, H. Hua, Z. F. Zhang, J.-N. Liu, J.-F. Guo, Y. Yao & K. Yasui. 2006. Lower Cambrian vendobionts from China and early diploblast evolution. Science 312: 731–734.