The dark phosphatic shell of conulariids and the skeleton of P. wrangeli stand out in the greenish-pale limestone, and if P. wrangeli were abundant, it would have been easy for the experienced and dedicated fossil hunters to find more material. The quarry exposed the Lyckholmsche Schicht (corresponding to the Nabala and Vormsi Regional stages) and, according to Schmidt (1874), was very rich in conulariids. It took him two years and hours of focused searching to find another good specimen in a small quarry, where Wrangell guided him and his younger Swedish colleague Jonas. In his original description of the fossil, Schmidt (1874) reported the difficulties in finding more material. Schmidt (1832–1908) to solve its mystery. Baron von Wrangell (1831–1894) (son of the famous seaman Ferdinand von Wrangel), who found this fossil not far from his manor house when he was a young man only to urge twenty years later the Geologist Friedrich K. P. wrangeli has a peculiar tetraradiate symmetry with four, strange horn-like spines or pillars at each corner, and it consists of a shiny, dark-brown calcium phosphate, which cannot be overlooked on a freshly broken Ordovician limestone. The fossil Palaenigma wrangeli ( Schmidt, 1874) is small, less than a small finger in diameter and no more than a couple of centimeters long. is proposed as the monotypic taxon for P. Here the new conulariinid family Palaenigmaidae fam. wrangeli can be best interpreted as a poorly mineralized conulariinid from an original soft bottom habitat. P. wrangeli often co-occurs with conulariids in fossil-rich limestone with mudstone–wackestone lithologies. wrangeli but is only rarely and fragmentary preserved. A non-mineralized or poorly mineralized external periderm existed originally in P. Marginally, the diaphragms and pillar lamellae are not connected to each other and thus do not form a closed periderm structure.
The lamellae form four semicircular marginal pillars, which are connected by irregularly spaced transverse diaphragms. wrangeli consists of an alternation of distinct calcium phosphate (apatite) lamellae and originally organic-rich inter-layers. The resulting 2D-, and 3D-scans reveal that P. Additionally, the elemental composition of the skeletal elements has been checked using energy dispersive X-ray spectroscopy. wrangeli have been reexamined using scanning electron microscopy and x-ray computed tomography (microCT). The systematic affinities and palaeoecology of P. Palaenigma wrangeli (Schmidt) is a finger-sized fossil with a tetraradiate conical skeleton it occurs as a rare component in fossiliferous Upper Ordovician strata of the eastern Baltic Basin and is known exclusively from north Estonia.
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