Rhabdopleura

Rhabdopleura is a genus of colonial sessile hemichordates belonging to the Pterobranchia class. As one of the oldest living genera with a fossil record dating back to the Middle Cambrian, it is also considered to be the only living genus of graptolites.

Rhabdopleura is the best studied pterobranch in developmental biology. Research in the 2010s by Jörg Maletz and other paleontologists and biologists have demonstrated that Rhabdopleura is an extant graptolite.

Species
List of species from Maletz (2014):

The genus Rhabdopleura contains at least five living species.
 * Living species


 * Rhabdopleura annulata Norman 1921 — Indo-Pacific region
 * Rhabdopleura compacta Hincks 1880 — Atlantic
 * Rhabdopleura normani Allmann, 1869 — Atlantic and parts of the Pacific
 * Rhabdopleura recondita Beli, Cameron and Piraino, 2018 — Mediterranean
 * Rhabdopleura striata Schepotieff 1909 — Pacific (Sri Lanka)


 * Nomina dubia (doubtful)
 * Rhabdopleura grimaldi Julien 1890 nomen dubium
 * Rhabdopleura manubialis Jullien & Calvet 1903 nomen dubium


 * Extinct species:
 * †Rhabdopleura delmari Mortelmans 1955
 * †Rhabdopleura graysoni Chapman, Durman & Rickards 1995
 * †Rhabdopleura hollandi Rickards, Chapman & Temple 1984
 * †Rhabdopleura kozlowskii Kulicki 1969
 * †Rhabdopleura obuti Durman & Sennikov 1993
 * †Rhabdopleura sinica Chapman, Durman & Rickards 1995
 * †Rhabdopleura vistulae Kozlowski 1956

Fossil record
The fossil record for Rhabdopleura dates back to the Middle Cambrian. There are also Rhabdopleura fossils from the Eocene.