Inquicus fellatus is an extinct, bowling pin-shaped gnathiferan[1] worm from the Chengjiang Biota, in what was once a marine environment from the Early Cambrian Yunnan province. Its fossils are found attached to fossils of the worms Cricocosmia and Mafangscolex in either a parasitic or commensalistic relationship.[2]

Inquicus
Temporal range: Early Cambrian
Restoration of individuals on host, Cricocosmia sp.
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Clade: Gnathifera
Genus: Inquicus
Cong, et al 2017
Species:
I. fellatus
Binomial name
Inquicus fellatus
Cong, et al 2017

Description edit

Inquicus individuals were up to three centimeters long, shaped like a bowling pin with an elongated body that tapered to a slightly bulbous head. They attached their bottom ends to their hosts, with their feeding appendages facing outwards and away from their hosts' bodies.[3]

Behavior edit

Although Inquicus attached to host worms, it is unlikely that the relationship was directly parasitic. The attachment point of Inquicus did not penetrate the skin of the hosts, but rather attached through suction. The species also was stiff, with there being no evidence that it could bend its mouth backwards to feed on the host. It is more likely that they simply rode on their hosts while browsing for food, or used them as a form of locomotion.[3]

References edit

  1. ^ Vinther, Jakob; Parry, Luke A. (2019). "Bilateral jaw elements in Amiskwia sagittiformis bridge the morphological gap between gnathiferans and chaetognaths". Current Biology. 29 (5): 881–888.e1. Bibcode:2019CBio...29E.881V. doi:10.1016/j.cub.2019.01.052. hdl:1983/51b1b6c1-0220-4469-977f-480e847a9101. PMID 30799238.
  2. ^ Cong, Peiyun; Ma, Xiaoya; Williams, Mark; Siveter, David J.; Siveter, Derek J.; Gabbott, Sarah E.; Zhai, Dayou; Goral, Tomasz; Edgecombe, Gregory D.; Hou, Xianguang (2017-08-28). "Host-specific infestation in early Cambrian worms". Nature Ecology & Evolution. 1 (10): 1465–1469. Bibcode:2017NatEE...1.1465C. doi:10.1038/s41559-017-0278-4. ISSN 2397-334X. PMID 29185506.
  3. ^ a b "Infested fossil worms show ancient example of symbiosis". www.nhm.ac.uk. Retrieved 2022-10-19.