''Worthenella'' is a genus of enigmatic

arthropod Arthropods ( ) are invertebrates in the phylum Arthropoda. They possess an arthropod exoskeleton, exoskeleton with a cuticle made of chitin, often Mineralization (biology), mineralised with calcium carbonate, a body with differentiated (Metam ...

from the

Burgess Shale The Burgess Shale is a fossil-bearing deposit exposed in the Canadian Rockies of British Columbia, Canada. It is famous for the exceptional preservation of the soft parts of its fossils. At old (middle Cambrian), it is one of the earliest fos ...

. It known from a single specimen described initially as an

annelid The annelids (), also known as the segmented worms, are animals that comprise the phylum Annelida (; ). The phylum contains over 22,000 extant species, including ragworms, earthworms, and leeches. The species exist in and have adapted to vario ...

Charles Doolittle Walcott Charles Doolittle Walcott (March 31, 1850February 9, 1927) was an American paleontologist, administrator of the Smithsonian Institution from 1907 to 1927, and director of the United States Geological Survey. He is famous for his discovery in 19 ...

in 1911. The body is elongate and

myriapod Myriapods () are the members of subphylum Myriapoda, containing arthropods such as millipedes and centipedes. The group contains about 13,000 species, all of them terrestrial. Although molecular evidence and similar fossils suggests a diversifi ...

-like with a head and at least 46 body segments. The head bears poorly preserved appendages, while filamentous branched structures appear to run along the underside of the first 34 trunk segments, with the posterior 8 suggested to have had longer appendages. In 2013, David Legg placed it in the family Kootenichelidae as a sister to ''

Kootenichela ''Kootenichela deppi'' is an extinct arthropod described from the Middle Cambrian of the Kootenay National Park, Canada. It is originally considered to be a member of "great appendage arthropods", although subsequent studies questioned its affini ...

'' , based on the supposed presence of antenniform head appendages. However, this position was questioned in a later study, which argued that the supposed antenniform appendages were actually

taphonomic Taphonomy is the study of how organisms decay and become fossilized or preserved in the paleontological record. The term ''taphonomy'' (from Greek , 'burial' and , 'law') was introduced to paleontology in 1940 by Soviet scientist Ivan Efremov ...

artefacts.

References

Megacheira Prehistoric arthropod genera Burgess Shale fossils Cambrian genus extinctions {{paleo-arthropod-stub