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| Callistoctopus xiaohongxu Zheng, Xu & Li, 2022 |
Abstract
In this study, we described a new species of octopus and named it Callistoctopus xiaohongxu sp. nov. based on nine specimens captured in the waters of southeast China. Callistoctopus xiaohongxu sp. nov. is a small to moderate-sized octopus. The most characteristic and defining morphological features are the reddish-orange to reddish-brown skin, gills with 8 or 9 lamellae per demibranch, \∧/-shaped funnel organ, and small suckers. Fragments obtained from the mitochondrial cytochrome c oxidase subunit I (COI) gene of nine specimens were 593 bp in length, and the genetic distance among the specimens of C. xiaohongxu sp. nov. and the other 16 octopods ranged from 11.13 to 21.09%. Topologies resulting from ML and BI analyses of the COI gene showed a highly supported monophyletic clade (bootstrap value [BS] = 94%, posterior probability [PP] = 100%) containing all the specimens identified as C. xiaohongxu sp. nov.
Keywords: Callistoctopus xiaohongxu sp. nov., COI gene, new species, octopus, taxonomy
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| Callistoctopus xiaohongxu sp. nov., holotype, male, 45.5 mm ML (OUC-201808200301) A photograph of dorsal view B photograph of ventral view. Scale bars: 10 mm (A, B). |
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| Callistoctopus xiaohongxu sp. nov. A proximal portion of arms 1–3 (left side), male, 49.5 mm ML (OUC-201812050301) B funnel organ, male, 53.2 mm ML (OUC-201812050302) C oral view of basal portion of arms, male, 63.2mm ML (OUC-201812050304) D distal portion of hectocotylus, male, 63.2 mm ML (OUC-201812050304). Abbreviations: c, calamus; l, ligula. Scale bars: 10 mm (B, C, D). |
Order Octopoda Leach, 1818
Family Octopodidae d’Orbigny, 1840
Genus Callistoctopus Taki, 1964
Type species: Callistoctopus ornatus (Gould, 1852).
Callistoctopus xiaohongxu sp. nov.
Diagnosis: Small to moderate size (ML 41.7–83.3 mm). Colour of skin reddish-orange to reddish-brown, no papillae or patch. One or two lines of black chromatophores on the lateral margins of arms under the skin (Fig. 2A). Head narrow (HWI 23.0–39.1). Arms of moderate length (ALI 154.9–336.3), thin (AWI 8.7–18.0). Web deep (WDI 15.7–22.9). Suckers small (SDI 5.0–6.9) and biserial. Enlarged suckers absent. Funnel organ \ /\ /-shaped, long (FLI 51.0–68.5). Gills with 8–9 lamellae per demibranch. Ligula moderate size (LLI 7.0–11.6) with groove.
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| Callistoctopus xiaohongxu sp. nov. A live specimen B net-like structure on web. |
Etymology: The name ‘xiaohongxu’, which refers to its small body size and reddish body colour, is the phonetic translation of the local Chinese name of this species in Zhangzhou, where specimens were collected.
Distribution: According to fishermen in Zhangzhou, this species is distributed in the East China Sea and the South China Sea, mainly in Quanzhou, Fujian Province to Shanwei, Guangdong Province.
Xiaodong Zheng, Chenxi Xu and Jiahua Li. 2022. Morphological Description and mitochondrial DNA-based Phylogenetic Placement of A New Species of Callistoctopus Taki, 1964 (Cephalopoda, Octopodidae) from the southeast waters of China. ZooKeys. 1121: 1-15. DOI: 10.3897/zookeys.1121.86264
