Strictocorniculum
| Strictocorniculum Temporal range: | |
|---|---|
Scientific classification  | |
| Kingdom: | Animalia |
| Clade: | Panarthropoda |
| Phylum: | †Lobopodia |
| Family: | †Hallucigeniidae |
| Genus: | †Strictocorniculum |
| Species: | †S. vanallerum |
| Binomial name | |
| †Strictocorniculum vanallerum Landing, 1995 | |
Strictocorniculum is an extinct genus of animals known from small coniform sclerites. The only known species is S. vanallerum. Fossils of this genus have been found in Early Cambrian strata of Massachusetts, New Brunswick, Nova Scotia and Newfoundland. It is currently interpreted as a lobopodian.
Discovery and naming
In 1988, Landing described small, slander shelly fossil elements that he attributed to the genus Rhombocorniculum which was thought to be a pseudoconodont. He believed that this form represented a new species of Rhombocorniculum. In 1995, he named a new species and genus for those elements: Strictocorniculum vanallerum. He also created the new family Strictocorniculidae and the superfamily Strictocorniculacea. Fossils belonging to this species have been discovered in the Brigus Formation (Nova Scotia) and the upper part of the Weymouth Formation (Massachusetts), that both correspond to the Callavia broeggeri trilobite Biozone. This Zone belongs to the regional Branchian Series (late Cambrian Stage 3 to early Cambrian Stage 4). Landing et al. also documented the presence of S. vanallerum in the BHr-II-1.6 and BHr-II-2.3 sections (Beaver Harbour, New Brunswick) of the Wade's Lane Formation which also belong to the Branchian Series. Landing also stated that S. vanallerum occurred in Newfoundland.
The genus name Strictocorniculum means "straight little horn". The specific name honors Linda Van Aller Hernick, who contributed to Cambrian-Devonian paleontology research.
Description and affinities
The sclerites of S. vanallerum reach 8 mm in length. They are nearly straight and have an almost circular cross-section. The surface of the sclerites is sculptured in a rhomboid pattern. They were first interpreted as pseudoconodont elements. Pseudoconodontida is an order that was created to designate coniform tooth-like elements of uncertain affinities. They differ from other conodont-like groups, such as protoconondonts, euconodonts and paraconodonts in their histological structure.
In 2013, Caron et al. suggested that several conodont-like taxa could actually represent hallucigenid lobopodian spines. They especially proposed a link between Rhombocorniculum, a close relative of Strictocorniculum, and Hallucigenia. In 2025, Knecht et al. published the following cladogram of lobopodians, in which both Rhombocorniculum and Strictocorniculum were recovered as Hallucigenia-like genera.
Cladrogram after Knecht et al.
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References
- ↑ Landing, Ed (1988). "Lower Cambrian of Eastern Massachusetts: Stratigraphy and Small Shelly Fossils". Journal of Paleontology. 62 (5). Paleontological Society: 661–695. ISSN 0022-3360. JSTOR 1305390.
- 1 2 3 4 Landing, Ed (1995). "Upper Placentian-Branchian Series of Mainland Nova Scotia (Middle-Upper Lower Cambrian): Faunas, Paleoenvironments, and Stratigraphic Revision". Journal of Paleontology. 69 (3). Paleontological Society: 475–495. doi:10.1017/S0022336000034879. ISSN 0022-3360. JSTOR 1306322.
- ↑ Collantes, Luis; Pereira, Sofia; Mayoral, Eduardo; Liñán, Eladio; Gozalo, Rodolfo (2021). "On Callavia (Trilobita) from the Cambrian Series 2 of Iberia with systematic status of the genus". Journal of Paleontology. 95 (6): 1226–1240. doi:10.1017/jpa.2021.46. ISSN 0022-3360.
- ↑ Herbosch, Alain; Verniers, Jacques (2011). "What is the biostratigraphic value of the ichnofossil Oldhamia for the Cambrian: a review". Geologica Belgica. 14 (3–4): 229–248. ISSN 1374-8505.
- ↑ Landing, Ed; Johnson, Susan C.; Geyer, Gerd (2008). "Faunas and Cambrian volcanism on the Avalonian marginal platform, southern New Brunswick". Journal of Paleontology. 82 (5): 884–905. doi:10.1666/07-007.1. ISSN 0022-3360.
- ↑ Caron, Jean-Bernard; Smith, Martin R.; Harvey, Thomas H. P. (2013-09-22). "Beyond the Burgess Shale: Cambrian microfossils track the rise and fall of hallucigeniid lobopodians". Proceedings of the Royal Society B: Biological Sciences. 280 (1767) 20131613. doi:10.1098/rspb.2013.1613. ISSN 0962-8452. PMC 3735267. PMID 23902914.
- 1 2 Knecht, Richard J.; McCall, Christian R. A.; Tsai, Cheng-Chia; Rabideau Childers, Richard A.; Yu, Nanfang (2025-07-23). "Palaeocampa anthrax, an armored freshwater lobopodian with chemical defenses from the Carboniferous". Communications Biology. 8 (1). Nature Publishing Group: 1080. doi:10.1038/s42003-025-08483-0. ISSN 2399-3642. PMC 12287526. PMID 40702124.