Bailiella aequalis

• Main Authors: Unger, Tanja, Hildenbrand, Anne, Stinnesbeck, Wolfgang, Austermann, Gregor
• Format: Other/Unknown Material
• Language: unknown
• Published: 2022
• Subjects: Biodiversity; Taxonomy; Animalia; Arthropoda; Trilobita; Ptychopariida; Conocoryphidae; Bailiella; Bailiella aequalis; Canada; Manuels River; Rudolph; Newfoundland
• Online Access: https://zenodo.org/record/7477288; https://doi.org/10.5281/zenodo.7477288

Bailiella aequalis (Linnarsson, 1882) (Fig. 8) Conocoryphe aequalis Linnarsson, 1882: 25, 26, pl. 4, figs 12-15. — Grönwall 1902: 92, pl. 1, fig. 22. Conocoryphe (C.) aequalis – Cobbold 1913: 32, pl. 3, figs 18a-c (?). Bailiella aequalis – Westergård 1950: 28, 29, pl. 5, fig. 13; pl. 6, figs 1-3. — Rudolph 1994: 191, pl. 23, figs 6, 7 (?). — Sdzuy 2000: 308, pl. 3, figs 11-15; pl. 7, figs 4-6 (?). Bailiella aff. aequalis – Šnajdr 1958: 166, pl. 35, figs 1-5. LECTOTYPE. — Specimen originally figured by Linnarsson (1882: pl. 14, fig. 12) and designated as lectotype by Westergård (1950). From the Ptychagnostus puntuosus Zone, lower portion, Andrarum, Scania, Sweden. DIAGNOSIS. — Cranidium width/length ratio of c. 2/1; anterior margin narrow; occipital ring without node; packed coarse granulose ornamentation, grains with flattened to impressed top (based on Linnarsson 1882, with modifications). MATERIAL EXAMINED. — One cranidium of Bailiella aequalis (NFM F-3811). Collected at 5.90 m (Fig. 2) of the Manuels River Formation, type locality, Conception Bay South, Newfoundland, Canada. OCCURRENCE. — Bailiella aequalis is a rare middle Cambrian species (Westergård 1950), which is here documented from southeastern Canada, eastern Newfoundland, in the Paradoxides hicksi Zone (Fig. 2). It is also reported from United Kingdom, England (Cobbold 1913), Sweden (Ptychagnostus punctuosus Zone; Westergård 1950), Denmark in Bornholm (Ptychagnostus punctuosus Zone; Rudolph 1994) and Germany (Sdzuy 2000). DESCRIPTION The cranidium is 40.0 mm wide and 21.0 mm long. The glabella is 11.0 mm wide and 12.0 mm long. It is very wellpreserved as an internal cast, with an anterior margin that appears to be folded backwards. REMARKS Bailiella aequalis is closely related to Bailiella tenuicincta (Linnarsson, 1879), but differs by a shorter preglabellar area and packed granulose ornamentation. The ornamentation of B.tenuicincta is fine granulose with scattered grains (Linnarsson 1882). According to Linnarsson (1882) B. aequalis lacks a node on ...