Taxonomy

Phylum: Porifera Grant,1836

Class:  Hexactinellida Schmidt, 1870

Order：uncertain

Family: uncertain

Genus：Sanshapentella Mehl and Erdtmann, 1994

Specie: Sanshapentella tentoriformis sp. nov. 2022

The complete body of the sponge can be subdivided into two parts: a stout trunk and a crown composed of four tent-like high peaks (named as conical branches). The total height of the holotype is 70 mm, in which the trunk is 42.5 mm high. The trunk is 28 mm in width while the crown is 50 mm wide at the widest region. The four conical branches (heights of the cones are 9, 12.5, 20 and 22 mm, respectively) of the crown can be grouped into two pairs (left pair and right pair), and these two pairs are approximately bilaterally symmetrical to each other. 

Two morphological series of spicules are recognized, including dermal pentactines that partly protrude out from the body and abundant substrate spicules that form the dense skeletal mesh. The dermal pentactines are quadripod-shaped, composed of a short ray pointing outwards and four long paratangential rays that bend towards the body. The substrate spicules, including diactines, stauractines, hexactines and hexactine-derived pentactines, are densely distributed and interlaced in both the trunk and the conical branches.
The spicules can be classified into three ranks by size. The first rank, ranging from 5 to 19 mm except in two small (juvenile) specimens, are the particularly large dermal pentactines; each of them serves as an overall framework of a conical branch. Paratangential rays of the large pentactines in the holotype, 8–13.5 mm in length and 0.1 mm in diameter, are arranged along the surface of each branch, reminiscent of the frame of a pagoda tent. The outward- pointing short rays are degenerated and no more than 0.5 mm long, forming the apex of the branch. The second rank, mostly 2.5–7.5 mm in size, is represented by a series of smaller dermal pentactines and substrate stauractines (and maybe some hexactines) that are scattered on the body surface. The paratangential rays of the small dermal pentactines  are 2.5–3.5 mm in length; and the tangential rays of the stauractines are 3–5.5 mm in length. The third rank, 1–3 mm in size, includes most substrate triaxons, stauractines and diactines in the skeletal mesh that generally have a small size. The arrangement of the substrate spicules is relatively irregular, though the second-rank stauractines seem to have rays usually obliquely crossing the main axis of the sponge body. Additionally, the conical branches framed by large dermal pentactines, as well as small triaxons, are not only observed on the bedding surface of sediments but also revealed inside the rock samples and some of the spicules are preserved three-dimensionally.

Age & Localities

Age: Cambrian Series2, Stage3