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DescriptionType material available to us has a flattened (Fig. 31A left), rounded shape, size 1×1×0.2 cm. It is a fragment of a larger holotype specimen (3.5×3×2.5 cm) that is massively rounded and may have a large central oscule (Fig. 31A right). Colour very pale green or dirty white. Skeleton: an irregular mass of large triaenes covered at the periphery by a thick layer of ataxasters / microrhabds, which are also strewn in the interior. Loose oxeas of widely different sizes present in moderate quantities, considered foreign. Spicules: calthrops, spheroxyasters, ataxasters. Calthrops (Fig. 31B) variable in size and thickness, mostly with straight cladi, often one cladus slightly shorter, occasionally curved at the ends; cladi 133–412.3–708 × 15–37.4–71 µm, cladome 233–626.8–1180 µm. Spheroxyasters (Fig. 31C), thick-centred with smooth conical rays, many of which appear underdeveloped causing an irregular aspect; extreme cases are the medusa-like forms such as pictured at lower right inFig 31C, showing a deformed aster with rays present only at one side; diameter (including rays) 15–18.1–24 µm (centre approx. 10 µm diameter). Ataxasters (Figs 31D–E), typically pyriform (pointed one-sidely), occasionally ovate or rounded, microspined all over, but spines tend to be grouped; no branching shapes were found, making the term ‘ataxaster’ inappropriate for these spicules, but their homology to the ataxasters ofPachataxa lithistinais nevertheless obvious; size 7–20.5–31 µm, measured along the longest axis.