Foxaspis
Foxaspis (IPA: [fɒksæspɪs]) (meaning "fox shield") is a genus of duyunolepidid galeaspid from the early Devonian (Pragian stage) Xiaoshan Formation in Guangxi, Southern China. The type and only species is F. novemura, known from two well-preserved specimens.[1]
| Foxaspis | |
|---|---|
| Photographs of the holotype and paratype | |
| Scientific classification | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Infraphylum: | Agnatha |
| Class: | Cephalaspidomorphi |
| Order: | †Polybranchiaspidiformes |
| Family: | †Duyunolepididae |
| Genus: | †Foxaspis Gai et al., 2023 |
| Type species | |
| †Foxaspis novemura Gai et al., 2023 | |
Discovery and naming
Foxaspis is known from two specimens that were described in 2023 by Gai et al. The holotype, IVPP V30958.1a-b consists of a complete headshield articulated with a body and tail. The paratype, IVPP V30958.2-3, consists of an incomplete headshield and exceptionally preserved tail.[1]
The generic name, "Foxaspis" (IPA: [fɒksæspɪs]), is derived from the English word "fox" and the Greek word "aspis", which roughly translates to "shield", meaning the generic name translates to "fox shield". The specific name, "novemura" (IPA: [no.vemˈuːrä]), derives from the Latin words "novem", which translates to "nine," and the suffix "-ura" which refers to the tail, meaning the specific name translates to "nine tails". It was named as such after the nine-tailed fox, a mythical beast mentioned in the Shanhai jing.[1]
Description
The tail of Foxaspis is notable, being asymmetrical with nine thin projections covered in scales. These spines may have been covered in a fin web. The tail of Tujiaaspis, a closely related galeaspid, lacked these structures and was generally symmetrical. Galeaspids like Foxaspis and Tujiaaspis were likely relatively fast swimmers compared to other contemporary jawless and jawed fish.[1]
References
- Gai, Zhikun; Lin, Xianghong; Shan, Xianren; Ferrón, Humberto; Donoghue, Philip (27 February 2023). "Postcranial disparity of galeaspids and the evolution of swimming speeds in stem-gnathostomes". National Science Review. 10 (2): nwad050. doi:10.1093/nsr/nwad050. hdl:10550/85976. PMC 10232041. PMID 37266551.