Noriaster Blake, Tintori & Hagdorn 2000

† Noriaster Blake, Tintori & Hagdorn 2000

(not figured)

Blake et al. 2000: 141,148

Type species: Noriaster barberoi Blake et al. 2000

Diagnosis. (From Blake et al. 2000). Carinals stout, peg-ike, subpaxillate to tabular. Other abactinals barshaped to ovate, variable in size, arranged in irregular longitudinal and trasverse series. Maginals robust. Inferomarginals enlarged, peg-like transversely elongate with flattened adradial and abradial surfaces. Inferomarginals abruptly truncated abradially. Terminus swollen. Ventral ossicle surface with one or two rows of two to four disjunct robust “pustules”.

Actinals arranged in two or three rows (quality of preservation does not allow positive identification of third row). Actinal ossicles disk-like and imbricated, irregular in outline. Actinal ossicles pear “pustules” similar to those on the inferomarginals.

Taxonomic comments. Blake et al. (2000) showed Marginaster as sharing the most similar actinal and marginal plate arrangements, relative to a paraphyletic “ Porania ” within the Poraniidae. Noriaster definitely shows morphological affinities with those living poraniids having a dense, imbricate skeleton and a robust marginal series such as Porania pulvillus rather than a poraniid with a more open, reticulate skeleton, such as Poraniopsis. However, the bar-shaped abactinals in irregular/transverse series are reminiscent of the reticulate skeletons in Bathyporania and “ Porania ” antarctica. Noriaster ’s poor state of preservation makes clear comparisons, if such comparisons can be made, with living material difficult.