Krommaster

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Krommaster
North Table Mountain & South Table Mountain (Pleistocene orendite volcanic centers in the Leucite Hills, Wyoming, USA) 2 (48933522908).jpg
An image of the Table Mountain Group where the species Krommaster spinosus and Hexuraster weitzi were discovered.
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Echinodermata
Class: Ophiuroidea
Order: Oegophiuroidea
Family: Encrinateridea
Genus: Krommaster
Type species
Krommaster spinosus

Krommaster is a genus of early ophiuroids (brittle stars [1] ) that lived nearlt 410 million years ago in the early Devonian period, South Africa, Baviaanskloof formation, upper unit, Cape super group, Table Mountain group, Eastern cape. [2] [3] This genus has one species which is Krommaster spinous. This species was discovered alongside Hexuraster weitzi , another species of brittle star living in the same area. [4] [5]

Description

This genus is characterized by their moderately large encrinasterid with a disk covered in a mosaic of small, thin scales and extending form the fifth and sixth arm segments. They also have conical pointed spines with similar but smaller spines on the dorsal disk and along the dorsal mid line of the arms. [6]

Reference

  1. "The Ophiuroidea". ucmp.berkeley.edu. Retrieved 2023-11-02.
  2. Reddy, Caitlin; Thuy, Ben; Reid, Mhairi; Gess, Robert (2023-10-25). "Earliest known ophiuroids from high palaeolatitude, southern Gondwana, recovered from the Pragian to earliest Emsian Baviaanskloof Formation (Table Mountain Group, Cape Supergroup) South Africa". PLOS ONE. 18 (10): e0292636. doi: 10.1371/journal.pone.0292636 . ISSN   1932-6203. PMC   10599496 . PMID   37878550.
  3. "Krommaster from the Baviaanskloof Formation, Upper Unit, Cape Supergroup, Table Mountain Group, Eastern Cape South Africa". figshare. 2023-10-25. doi: 10.1371/journal.pone.0292636.g005 . Retrieved 2023-11-02.
  4. Reddy, Caitlin; Thuy, Ben; Reid, Mhairi; Gess, Robert (2023). "Earliest known ophiuroids from high palaeolatitude, southern Gondwana, recovered from the Pragian to earliest Emsian Baviaanskloof Formation (Table Mountain Group, Cape Supergroup) South Africa". PLOS ONE. 18 (10): e0292636. doi: 10.1371/journal.pone.0292636 . ISSN   1932-6203. PMC   10599496 . PMID   37878550.
  5. Anderson, Natali (2023-11-01). "410-Million-Year-Old Brittle Star Fossils Uncovered in South Africa | Sci.News". Sci.News: Breaking Science News. Retrieved 2023-11-02.
  6. Reddy, Caitlin; Thuy, Ben; Reid, Mhairi; Gess, Robert (2023-10-25). "Earliest known ophiuroids from high palaeolatitude, southern Gondwana, recovered from the Pragian to earliest Emsian Baviaanskloof Formation (Table Mountain Group, Cape Supergroup) South Africa". PLOS ONE. 18 (10): e0292636. doi: 10.1371/journal.pone.0292636 . ISSN   1932-6203. PMC   10599496 . PMID   37878550.

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