Heteractinida

Heteractinida
Scientific classification
Kingdom:	Animalia
Phylum:	Porifera
Stem group:	Hexactinellida
Informal group:	†"Heteractinida"; Hinde, 1887
Included groups
	See text
Synonyms
	Octactinellidae Hinde, 1887; Heteractinellidae Hinde, 1887; Wewokellida Croneis & Toomey, 1965;

The Heteractinids are a grade of sponges that are paraphyletic with respect to Hexactinellida.^[1] Their distinctive trait is their six-pronged (snowflake-like) spicules, whose symmetry historically suggested a relationship with the triradial Calcarean sponges.^[1] Nevertheless, they actually represent a polyphyletic grade, from which the hexactinellids arose.^[1]

Families[]

The following families are placed in Heteractinida:^[2]

† Miller, 1889
†Eiffeliidae Rigby, 1986
† Pickett, 2002
† King, 1943

References[]

^ ^a ^b ^c Botting, J. P.; Butterfield, N. J.; Valentine, J. W. (2005). "Reconstructing early sponge relationships by using the Burgess Shale fossil Eiffelia globosa, Walcott". Proceedings of the National Academy of Sciences of the United States of America. 102 (5): 1554–1559. doi:10.1073/pnas.0405867102. JSTOR 3374469. PMC 547825. PMID 15665105.
^ Pickett, J. (2002). "†Order Heteractinida Hinde, 1887". In Hooper, J.N.A.; Van Soest, R.W.M.; Willenz, P. (eds.). Systema Porifera: A Guide to the Classification of Sponges. Boston, MA: Springer. pp. 1121–1140. doi:10.1007/978-1-4615-0747-5_117. ISBN 978-0-306-47260-2.

This poriferan- (or sponge-) related article is a stub. You can help Wikipedia by .

[ref_-1] Botting, J. P.; Butterfield, N. J.; Valentine, J. W. (2005). "Reconstructing early sponge relationships by using the Burgess Shale fossil Eiffelia globosa, Walcott". Proceedings of the National Academy of Sciences of the United States of America. 102 (5): 1554–1559. doi:10.1073/pnas.0405867102. JSTOR 3374469. PMC 547825. PMID 15665105.

[2] Pickett, J. (2002). "†Order Heteractinida Hinde, 1887". In Hooper, J.N.A.; Van Soest, R.W.M.; Willenz, P. (eds.). Systema Porifera: A Guide to the Classification of Sponges. Boston, MA: Springer. pp. 1121–1140. doi:10.1007/978-1-4615-0747-5_117. ISBN 978-0-306-47260-2.

[1]

[2]