Cambroraster

Cambroraster
Temporal range: Mid Cambrian: Chengjiang–Burgess shale
Fossil of a Cambroraster head sclerite (ROMIP 65079)
Video animation
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Arthropoda
Order: †Radiodonta
Family: †Hurdiidae
Genus: †Cambroraster
Moysiuk & Caron, 2019
Type species
Cambroraster falcatus
Moysiuk & Caron, 2019
Species
  • Cambroraster falcatus Moysiuk & Caron, 2019
Reconstruction of the head region of Cambroraster falcatus. A: Dorsal view, B: Ventral view, Ey: Eye, Fa: Frontal appendage, He:H-element, Bp: Bilobate posterior region, Lp: Posterolateral process, Oc: Oral cone, Pe: P-element, Pn: P-element neck

Cambroraster is an extinct monotypic genus of hurdiid radiodont, dating to the middle Cambrian, and represented by the single formally described species Cambroraster falcatus.[1] Hundreds of specimens were found in the Burgess Shale, and described in 2019.[2] A large animal (for its era) at up to 30 centimetres (12 in) (but not as long as Titanokorys at 50 centimetres (20 in)), it is characterized by a significantly enlarged horseshoe-shaped dorsal carapace (H-element), and presumably fed by sifting through the sediment with its well-developed tooth plates (oral cone) and short frontal appendages with hooked spines.[1] Nicknamed the "spaceship" fossil when first found, for the way its dorsal carapace resembles the fictional Millennium Falcon, the specific epithet falcatus in its scientific name is a nod to that resemblance.[1][3][4]

  • Reconstruction
    Reconstruction
  • Head sclerites
    Head sclerites
  • Frontal appendage
    Frontal appendage
  • Movement range of the frontal appendage
    Movement range of the frontal appendage

A second species of Cambroraster is known from the Chengjiang Biota of South China, making it the first uncontroversial hurdiid from the Cambrian of China. This species is known only from a juvenile dorsal carapace, so it was not given a specific name.[5]

Although originally suggested to have used its frontal appendages to sift sediment for prey, a later study by different authors suggested that it may have been a filter feeder instead.[6]

  1. ^ a b c Moysiuk, J.; Caron, J.-B. (31 July 2019). "A new hurdiid radiodont from the Burgess Shale evinces the exploitation of Cambrian infaunal food sources". Proceedings of the Royal Society B: Biological Sciences. 286 (1908): 20191079. doi:10.1098/rspb.2019.1079. PMC 6710600. PMID 31362637.
  2. ^ Wu, Katherine J. (30 July 2019). "Meet Cambroraster falcatus, the sediment-sifting 'Roomba' of the Cambrian". Nova. Retrieved 31 July 2019.
  3. ^ "A voracious Cambrian predator, Cambroraster, is a new species from the Burgess Shale". Phys.org. Royal Ontario Museum. 30 July 2019. Retrieved 4 August 2019.
  4. ^ "Scientists name new fossil species after Millennium Falcon from Star Wars". Ars Technica. 3 August 2019. Retrieved 4 August 2019.
  5. ^ Liu, Yu; Lerosey-Aubril, Rudy; Audo, Denis; Zhai, Dayou; Mai, Huijuan; Ortega-Hernández, Javier (2020). "Occurrence of the eudemersal radiodont Cambroraster in the early Cambrian Chengjiang Lagerstätte and the diversity of hurdiid ecomorphotypes". Geological Magazine. 157 (7): 1200–1206. Bibcode:2020GeoM..157.1200L. doi:10.1017/S0016756820000187. ISSN 0016-7568.
  6. ^ De Vivo, Giacinto; Lautenschlager, Stephan; Vinther, Jakob (2021-07-28). "Three-dimensional modelling, disparity and ecology of the first Cambrian apex predators". Proceedings of the Royal Society B: Biological Sciences. 288 (1955): 20211176. doi:10.1098/rspb.2021.1176. ISSN 0962-8452. PMC 8292756. PMID 34284622.