Molecular and morphological evidence supports recognizing Homoscleromorpha as a fourth sponge class rather than retaining it within Demospongiae; this taxonomic revision is not an origin-time claim.
claim:taxon:homoscleromorphaAtlas home / References / No longer Demospongiae: Homoscleromorpha formal nomination as a fourth class of Porifera
References / paperNo longer Demospongiae: Homoscleromorpha formal nomination as a fourth class of Porifera
Gazave, E.; Lapébie, P.; Ereskovsky, A.V.; et al.
Year2012
Source rolesystematic-review
DOI / ID10.1007/s10750-011-0842-x
Fitness and scope
taxonomy · topology · morphology
Formal class-level revision synthesizing molecular and morphological evidence; it does not date Homoscleromorpha or prove a direct ancestor.
Claim ledger
Homoscleromorpha has no supported scalar temporal range in the cited evidence: formal recognition of the living class supplies taxonomy but no fossil boundary, so the former 0–0 placeholder is withheld rather than presented as a range.
claim:taxon:homoscleromorpha:range-boundary-rc50