Elasmobranchii (haaien en roggen) (sharks and rays) >
Squaliformes (Sleeper and dogfish sharks) >
Somniosidae (Sleeper sharks)
Etymology: Somniosus: Latin for sleepy, reflecting Lesueur’s surmise that these sharks are slow or sluggish because of their relatively small fins (hence the name sleeper sharks) (See ETYFish); cheni: In honor of Wen-Jong Chen, Taitung Xin Gang District Fisherman’s Association, for contributions of chondrichthyan fish samples and research assistance with Taiwan and international research for over 30 years (See ETYFish).
Eponymy: Wen-Jong Chen, of the Taitung Xin Gang District Fisherman’s Association, was honoured for his contributions of shark samples and his assistance with Taiwanese and international shark research for over 30 years. (Ref. 128868), visit book page.
Milieu: milieu / Klimaatzone / Diepte / verspreidingsgebied
Ecologie
marien bathydemersaal; diepte 500 - ? m (Ref. 123759). Subtropical
Northwest Pacific: Taiwan.
Grootte / Gewicht / Leeftijd
Maturiteit: Lm ?  range ? - ? cm
Max length : 14.7 cm TL mannelijk / geslacht onbekend; (Ref. 123759); 13.6 cm TL (female)
Korte beschrijving
Determinatiesleutels | Morfologie | Morfometrie
Wervels: 75 - 79. This species is distinguished from its congeners by the following set of characters: no anal fin; two spineless dorsal fins, first dorsal fin higher and larger than second dorsal fin; short lateral keels on the caudal peduncle, precaudal pits absent; caudal fin is asymmetrical and paddle-shaped, with a relatively short upper lobe and long lower lobe; rhomboid-shaped dermal denticles; teeth dissimilar in upper and lower jaws, upper-jaw teeth small with lanceolate, in 72 rows, lower-jaw teeth semioblique with low roots, in 28 rows; precaudal vertebrae 60-61, caudal vertebrae 15-18, total 75-78; number of turns in spiral valve 25-26 In mid-term embryo stage (12.8-15.0 cm TL); no teeth and dermal denticles; sexes identifiable; caudal keel present. Colouration: body light brown to yellow-grayish (Ref. 123759).
Cross section: oval.
This species was collected in canyons surrounded by deep-sea longliner off eastern Taiwan at a depth greater than 500 m (Ref. 123759).
Levenscyclus en paargedrag
Maturiteit | Voortplanting | Paaien | Eieren | Fecunditeit | Larven
Hsu, H.-H., C.-Y. Lin and S.-J. Joung, 2020. Somniosus (Rhinoscymnus) cheni sp. nov. A new species of sleeker shark (Squaliformes: Somniosidae) from Eastern Taiwan, with aspects of embryo biology. Zool. Stud. 59:48. (Ref. 123759)
Status op de Rode Lijst van het IUCN (Ref. 130435: Version 2025-2 (Global))
Gevaar voor de mens
Harmless
Gebruik door de mens
Visserij: van geen belang
Tools
Speciale rapporten
Download XML
Internetbronnen
Schattingen op basis van modellen
Fylogenetische diversiteitsindex (Ref. 82804) |
PD50 = 0.5156 [Uniqueness, from 0.5 = low to 2.0 = high]. |
|
Bayesian length-weight
|
a=0.00389 (0.00170 - 0.00889), b=3.12 (2.93 - 3.31), in cm total length, based on LWR estimates for this (Sub)family-body shape (Ref. 93245). |
Trofisch niveau (Ref. 69278) |
3.5 ±0.4 se; based on size and trophs of closest relatives |
Weerstandsvermogen (Ref. 120179) |
Gemiddeld, minimale populatieverdubbelingstijd 1,4-4,4 jaar (Preliminary K or Fecundity.). |
Kwetsbaarheid van de visserij (Ref. 59153) |
Moderate vulnerability (36 of 100). 🛈 |