This is Mazon Monday post #105. What's your favorite Mazon Creek fossil? Tell us at email:[email protected].
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Kellibrooksia macrogaster is a species of mantis shrimp (stomatopods). It was described by Frederick Schram in 1973. Frederick Schram described many of the shrimp of Mazon Creek. It is a rarely found species. We had a nice one for sale at the ESCONI Gem, Mineral, and Fossil show in March 2022. Kellibrooksia is named in honor of Harold Kelly Brooks, who published the first well-illustrated modern account of Mazon Creek crustaceans. A pdf of the full article is available and it has some amazing illustrations!
K. macrogaster appears in the "The Mazon Creek Fossil Fauna" by Jack Wittry on Page 90.
Kellibrooksia macrogaster has thin, weak thoracic legs and a poorly developed tail fan with a long styliform telson. The body is very long, and each body segment becomes progressively longer towards the tail. This animal has compound eyes and a body plan similar in design to modern stomatopods (mantis shrimp). This suggests it may have been an opportunistic bottom-dweller that ambushed passing prey.
Frederick Schram has a nice description of the species in chapter 12 "" of the "Richardson's Guide to the Fossil Fauna of Mazon Creek".
Carapace short without hinged rostrum; com pound eyes stalked; antenna (antennule?) with robust articles, possibly subchelate; thoracic limbs very short and apparently delicate; abdomen very long with segments progressively longer distally in the sequence; telson as a long spike with tiny caudal rami flanking the base. No clear preservation of thoracic and abdominal legs has ever been seen, suggesting that these were possibly thin, leaflike structures.
The form of these strange animals is similar to that of the stomatopod hoplocaridans, and suggest these too may have been bottom dwellers that buried themselves lying in wait for prey.
Kellibrooksia is a phyllocarid named after Harold Kelly Brooks, who published the first well-illustrated modern account of Mazon Creek crustaceans.
Specimens
These photos were provided by ESCONI member David Duck.
