Decumbispongia, Botting & Muir & Li & Lin, 2013

Botting, Joseph P., Muir, Lucy A., Li, Xiang-Feng & Lin, Jih-Pai, 2013, An enigmatic, possibly chemosymbiotic, hexactinellid sponge from the early Cambrian of South China, Acta Palaeontologica Polonica 58 (3), pp. 641-649 : 642

Genus Decumbispongia nov.

Etymology: From the Latin decumbo, to fall or lie down, referring to the inferred life position. Gender feminine.

Type species: Decumbispongia yuani sp. nov., by monotypy; see below.

Diagnosis.—Semi−toroid, cylindrical hexactinellid with rounded proximal and distal ends, one tapering slightly more than the other; dermal spiculation consisting of moderately regular, orthogonal and diagonal hexactines/clinopentactines of several size orders; no osculum or attachment structure.

Remarks.—The unique form of this sponge differs from all others described, either fossil or Recent. The implications of this morphology are discussed below. The dermal spiculation is similar to that of many reticulosans, and does not suggest any particular phylogenetic affiliation.