Deuterostomia

Specimen of Vetulicola cuneata (scale bar 5 mm), with close-up of lateral groove structure (scale bar 1 mm), from Donoghue & Purnell (2009).

Belongs within: Bilateria.
Contains: Hemichordata, Echinodermata, Chordata.

The Deuterostomia are a group of animals characterised by features of embryonic development including radial cleavage, and development of the blastopore into the anus. Possible synapomorphies of this group (albeit lost or modified in many subgroups) also include the presence of gill slits and the endostyle (Shu et al. 2001).

<==Deuterostomia [Cristozoa, Dexiothetica]
    |--Vetulicolia SCM04
    |    |  i. s.: Yuyuanozoon BL05
    |    |--Heteromorphida EL11
    |    |    |--Heteromorphus EL11
    |    |    `--Banffia Walcott 1911 EL11, H62
    |    |         |--*B. constricta Walcott 1911 H62
    |    |         `--B. confusa Chen & Zhou 1997 BL05
    |    |--Yunnanozoa [Yunnanozoida, Yunnanozoonidae] SCM03
    |    |    |--*Yunnanozoon lividum Hou et al. 1991 SCM03, D95
    |    |    `--Haikouella Chen, Huang & Li 1999 SCM03
    |    |         |--*H. lanceolata SCM03
    |    |         `--H. jianshanensis Shu, Conway Morris et al. 2003 SCM03
    |    `--Vetulicolida BL05
    |         |--Pomatrum ventralis SCM01
    |         |--Xidazoon Shu, Conway Morris & Zhang in Shu, Conway Morris et al. 1999 SCM01, SCM99
    |         |    `--*X. stephanus Shu, Conway Morris & Zhang in Shu, Conway Morris et al. 1999 SCM99
    |         |--Didazoon Shu & Han in Shu, Conway Morris et al. 2001 SCM01
    |         |    `--*D. haoae Shu & Han in Shu, Conway Morris et al. 2001 SCM01
    |         |--Skeemella Briggs, Lieberman et al. 2005 BL05
    |         |    `--*S. clavula Briggs, Lieberman et al. 2005 BL05
    |         `--Vetulicola BL05
    |              |--V. cuneata Hou 1987 [=V. cuneatus] BL05
    |              `--V. rectangulata SCM01
    |--+--Eldonia ludwigi EL11, CM98
    |  `--Herpetogaster EL11
    `--+--Ambulacraria [Coelomopora] SCM04
       |    |--Hemichordata SCM04
       |    `--+--Echinodermata SCM04
       |       `--Vetulocystidae [Vetulocystida] SCM04
       |            |--Vetulocystis Shu, Conway Morris et al. 2004 SCM04
       |            |    `--*V. catenata Shu, Conway Morris et al. 2004 SCM04
       |            `--Dianchicystis Shu, Conway Morris et al. 2004 SCM04
       |                 `--*D. jianshanensis Shu, Conway Morris et al. 2004 SCM04
       `--Chordata SCM04

*Type species of generic name indicated

REFERENCES

[BL05] Briggs, D. E. G., B. S. Lieberman, S. L. Halgedahl & R. D. Jarrard. 2005. A new metazoan from the Middle Cambrian of Utah and the nature of the Vetulicolia. Palaeontology 48 (4): 681–686.

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

[D95] Dzik, J. 1995. Yunnanozoon and the ancestry of chordates. Acta Palaeontologica Polonica 40: 341–360.

[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.

[H62] Howell, B. F. 1962. Worms. In: Moore, R. C. (ed.) Treatise on Invertebrate Paleontology pt W. Miscellanea: Conodonts, Conoidal Shells of Uncertain Affinities, Worms, Trace Fossils and Problematica pp. W144–W177. Geological Society of America, and University of Kansas Press.

[SCM99] Shu, D., S. Conway Morris, X.-L. Zhang, L. Chen, Y. Li & J. Han. 1999. A pipiscid-like fossil from the Lower Cambrian of south China. Nature 400: 746–749.

[SCM01] Shu, D.-G., S. Conway Morris, J. Han, L. Chen, X.-L. Zhang, Z.-F. Zhang, H.-Q. Liu, Y. Li & J.-N. Liu. 2001. Primitive deuterostomes from the Chengjiang Lagerstätte (Lower Cambrian, China). Nature 414: 419–424.

[SCM04] Shu, D.-G., S. Conway Morris, J. Han, Z.-F. Zhang & J.-N. Liu. 2004. Ancestral echinoderms from the Chengjiang deposits of China. Nature 430: 422–428.

[SCM03] Shu, D., S. Conway Morris, Z. F. Zhang, J. N. Liu, J. Han, L. Chen, X. L. Zhang, K. Yasui & Y. Li. 2003. A new species of yunnanozoan with implications for deuterostome evolution. Science 299: 1380–1384.