The Chinese Longnose Dogfish (Squalus acutirostris) is a dogshark in the family Squalidae. It is a very poorly known benthic or deepsea shark from the South China Sea. Its taxonomic status needs to be evaluated as it is considered by some to be a junior synonym of the Shortspine Spurdog (Squalus mitsukurii). According to the original accepted description, below describes the shark.
Family: Squalidae – Dogfish Sharks
Genus: Squalus
Species: acutirostris
Phylum– Chordata
Class– Chondrichthyles
Subclass– Elasmobranchii
Common Name– Dogfish Sharks
Family– Squalidae
Common Name– Dogfish Sharks
Genus– Squalus
Species– acutirostris
Status: IUCN Red List DATA DEFICIENT
Average Size and Length: At least between 2.1 and 2.9 feet based on holotype information below.
Current Rare Mythical Sightings: see holotype information:
Holotype No. D01562: total length 651mm, collected on April 21, 1982, at the depth 394m in South China Sea, kept in South China Sea Fisheries Research Institute.
Holotype No. D01567: total length 719mm.
Holotype No. D01548: 895mm.
Holotype No. D01473: 719mm, collected on April 13 and 21, 1982, depth 492-525 m in South China Sea, kept in Shanghai Fisheries College.
Teeth and Jaw: The mouth of the Chinese Longnose dogfish is broad and only slightly arched, its width is3/5-4/5 in the preoral length. The teeth are similar in both jaws, being smooth edged with a single sharp cusp. The inner margin is curved outward to form a transverse cutting edge.
Head: The head of the Chinese Longnose dogfish is long, depressed, a little less than 1/4 of total length. Length of snout 1.3-1.5 times of eye diameter. The eyes are large, oval and do not have nictitating membranes or fold; its horizontal diameter about 2.3-2.5 times of the nostrils. The nostrils are small and slightly oblique with an anterior nasal valve in a subtriangular lobe. There is a very small lobe at its base. Its inner end IS nearer to tip of snout than to mouth.
Tail: The tail of the Chinese Longnose dogfish is slender, about equal in the length of head and trunk. The caudal fin is 1/5 in total length. Ventral entirely anterior to the 2nd dorsal fin.
Demographic, Distribution, Habitat, Environment and Range: South China Sea. It is unknown if they are in Japan; Korea, Republic of; Taiwan, Province of China; Viet Nam. Between at least 1,293 and 1,722 feet based on holotype information provided.
Aesthetic Identification: The Chinese Longnose dogfish is dark brown to a brownish-white below. The body of the Chinese Longnose dogfish is elongated. The gill openings are small, in front of the pectorals and located low down on sides. The dorsal spines are strong. The first dorsal fin is small. The second dorsal fin is smaller than 1st dorsal fin and the length of under margin 1.2-1.4 times of its height and 1.2-1.3 times of its anterior margin. The posterior tip is sharply pointed. The pectoral fins are wide, subtriangular and the length of the anterior margin; 1.8 times that of the snout.
The Chinese Longnose dogfish differs from S. brevirostris Tanaka, 8. mitsukurii Jordan et Fowler of China and Japan, and 8. fernandinus Molina of Australia in under margin of 2nd dorsal 1.2-1.4 times of its height and 1.2-1.3 times of its anterior margin (vs. shorter); Length of snout 1.3-1.5 times of eye diameter (vs. about equal in S. “brevirostris and 8. fernandinus, 2.0 times in 8. mitsukurii); length of anterior margin of pectorals 1.8 times of snout (vs. 2.6 in S. brevirostris, 2.7-2.8 in S. mitsukurii and 8. fernandinus).
Biology and Reproduction: Unknown.
Behavioral Traits, Sensing and Intelligence: Unknown.
Chinese Longnose Dogfish Future and Conservation: The only known specimens were taken April 13–21 1982 (Chu, Meng & Li, 1984). There is not enough past data, and no current data surrounding this species.
Chinese Longnose Dogfish Recorded Attacks on Humans: Not a threat to humans.
Classification and the only known specimens were taken Chu, Meng & Li, 1984. The only known literature references are:
Chu, Y.T., Meng, Q.W. and Li, S. 1984. “Description of a new species of Squalidae of China”. Oceanlogia et Limnologia Sinica 15: 283-286.
IUCN. 2012. IUCN Red List of Threatened Species (ver. 2012.1). Available at: http://www.iucnredlist.org. (Accessed: 19 June 2012).
Munoz-Chapuli, R. and Ramos, F. 1989. “Morphological comparison of Squalus blainvillei and S. megalops in the eastern Atlantic, with notes on the genus”. Japanese Journal of Ichthyology 36: 6-21.
White, W.T. and P.R. Last. (2013). “Notes on shark and ray types at the South China Sea Fisheries Research Institute (SCSFRI) in Guangzhou, China”.