First report of Chelediscus Rushton, 1966 (Trilobita) from Western Gondwana, with description of a new species from the Cambrian Series 2 of Spain

ABSTRACT

Chelediscus is reported for the first time from the Cambrian of Western Gondwana. This eodiscide genus is known from the Cambrian Series 2 of England, Newfoundland, New York, Sweden and Russia. An emended diagnosis for the genus is provided, which is here assigned to Calodiscidae, and a new species, Chelediscus garzoni sp. nov. is described. The species comes from Cumbres de San Bartolomé municipality, northern Huelva province (Spain), in the upper part of the ‘Cumbres beds’ formation. This horizon is assigned to the regional upper Marianian Stage based on the trilobite assemblage (Serrodiscus Zone), correlating with the lowermost Cambrian Stage 4. Chelediscus carus Repina from the Botoman of Siberia and this Spanish occurrence are the earliest appearances of the genus. The new species suggests that a smooth, unlobed glabella is primitive for the genus. Chelediscus in Spain strengthens faunal links with Avalonia, Baltica, Siberia and Laurentia.

urn:lsid:zoobank.org:act:32A57670-48E7-470E-B7AD-A0ACACB2E5C6

KEYWORDS:

• Eodiscida
• Ossa-Morena Zone
• Huelva
• Cambrian Stage 4
• Marianian

Acknowledgment

We thank Lukáš Laibl and Peter Jell for their kind and useful reviews and the improvement of the English along the manuscript. We thank the Council of Environment and Territorial Planning from the Junta de Andalucía and the Directorate of Sierra de Aracena y Picos de Aroche Natural Park for facilitating fieldwork permission. We are also indebted to Scott Morrison and Prof. Igor V. Korovnikov for providing literature and advice on the Siberian occurrence of Chelediscus. We also thank Nia Schamuells for illustrating Chelediscus garzoni in Figure 3. The present work has been carried out with financial help from Junta de Andalucía to the RNM 276 Research Group and the Centro Científico-Tecnológico de Huelva, with the GIUV2017-395 research group of the University of Valencia. This work is a contribution to the project IGCP 652.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the Fundação para a Ciência e a Tecnologia [UI/DB/151298/2020, UIDB/00073/2020, UIDP/00073/2020].