Cornulitida

Cornulitida is an extinct order of encrusting animals from class Tentaculita, which were common around the globe in the Ordovician to Devonian oceans, and survived until the Carboniferous.^[1][2][3] Organisms that may be the oldest cornulitids have been found in Cambrian sediments of Jordan.^[4]

Cornulitida Temporal range: Mid Ordovician–Late Carboniferous[1] PreꞒ Ꞓ O S D C P T J K Pg N
Cornulitid on a brachiopod valve (Upper Ordovician, SE Indiana)
Scientific classification
Kingdom:	Animalia
Class:	†Tentaculita
Order:	†Cornulitida Boucek, 1964
Genera
Cornulites Conchicolites Cornulitella Cornulitozoon Opatozoon Reticornulites Septalites Coralloconchus

Cornulitids had shells, and were subject to predation by boring and other means from the Ordovician onwards. Many survived attacks by predators.^[1] Several cornulitids were endobiotic symbionts in the stromatoporoids and tabulates.^[5][6][7]

Their affinity is unknown; they have been placed in many phyla, and have been considered worms, corals, molluscs and more.^[1] They appear to be closely related to other taxa of uncertain affinity, including the microconchids, trypanoporids and tentaculitids.^[1]

Gallery

• 
  Cornulitids on a bryozoan; Bellevue Member, Grant Lake Formation, northern Kentucky
• 
  Conchicolites sp. overview of the rings with spines, Lilla Karlsö, Sweden
• 
  Septalites septatus from the Silurian of Gotland
• 
  Cornulites cellulosus from Wenlock of Saaremaa, Estonia