Spartobranchus tenuis

Spartobranchus tenuis is an extinct species of acorn worms (Enteropneusta). It existed in the Middle Cambrian (505 million years ago). Petrified mark animals were found in British Columbia, Canada in the formation Burgess Shale. It is similar to the modern representatives of the family Harrimaniidae, distinguished by branching fiber tubes. It is a believed predecessor of Pterobranchia, but this species is intermediate between these two classes. Studies show that these tubes were lost in the line leading to modern acorn worm, but remained in the extinct graptolites and saving still perystozyabernyh.

Description[]

Detailed analysis shows that Spartobranchus tenuis had flexible body consisting of short proboscis, collar and narrow elongated stem that ends bulbous structure that may have served as an anchor. The most complete specimens reached 10 centimeters long proboscis of about half a centimeter in length. Most of these worms has been retained in the pipes, some of which have branched assumed that the tubes were used as housing.

References[]

• Jean-Bernard Caron, Simon Conway Morris & Christopher B. Cameron. Tubicolous enteropneusts from the Cambrian period. Nature 495, 503–506 (28 March 2013) doi:10.1038/nature12017

External links[]

• Phallus-shaped fossils identified as new species, 13 March 2013, Michelle Warwicker, BBC