Bundenbach Regulaecystis pleurocystoides
4.0 cm (fossil), 11×12.5 cm (matrix)
Bundenbach; Obereschenbach pit
Very rare cystoid on unbroken plate with excellent details.
Regulaecystis pleurocystoides – The armored jewel from the Hunsrück slate
Exclusivity in pouch form: one of the rarest cystoids in the world.
If there is one fossil that epitomizes the uniqueness of the Bundenbach slate, then it is Regulaecystis pleurocystoides. This species is not only extremely rare, it is also an endemic – it is found exclusively in the famous slate quarries of the Hunsrück. A fossil for collectors who want to combine the local with the spectacular.
The distinctive features – what characterizes Regulaecystis pleurocystoides:
- The “pouch-shaped” carapace: The theca (the body) impresses with its striking pouch shape. It is composed of numerous polygonal plates that look like a precise mosaic. This structure gives the fossil a wonderful geometric texture and an almost technical aesthetic.
- The bordered anal area: a detail for the connoisseur’s eye: The anal field is enclosed by clear border strips. This “framing” provides a clear outline within the plate armor and is a real highlight on well-preserved pieces.
- The two powerful “antennae”: The two powerful arms (brachiola) are unique in appearance. They protrude from the body like antennae and give the otherwise compact fossil a fascinating directional dynamic.
- A stalk with a history: The stalk of Regulaecystis is surprisingly long. Particularly characteristic of finds from Bundenbach is an often-observed kink in the stalk – a sign of the original embedding in the mud, which gives the fossil an additional, dramatic note.
A masterpiece of primeval armor
Cystoids such as Regulaecystis are the architects among echinoderms. The way in which the polygonal plates interlock to provide protection for the body is a fascinating testimony to evolution. As these animals are only preserved in this level of detail in very few places worldwide, every piece is a scientific treasure.
