Common names
Musola gris, Emissole côtière, Émissole, Japanese gray smooth hound, Spotless smooth hound, Spotless smooth-hound

Short Description
Diagnosis after Compagno, 1984 [517]: Body fairly slender. Head short, prepectoral length 17 to 21% of total length; snout moderately long and bluntly angular in lateral view, preoral snout 5.7 to 7.1% of total length, preorbital snout 6.2 to 7.7% of total length; internarial space broad, 2.4 to 3.2% of total length; eyes fairly small, eye length 2.3 to 3.1 times in preorbital snout and 2.1 to 3.5% of total length; interorbital space narrow, 3.6 to 4.5% of total length; mouth fairly long, somewhat greater than eye length and 2.5 to 3.7% of total length; upper labial furrows equal or slightly shorter than lowers and 0.8 to 1.4% of total length; teeth molariform and asymmetric, with cusp reduced to a low point, cusplets absent except in very young sharks; buccopharyngeal denticles covering anterior half of palate and mouth floor. Interdorsal space 18 to 22% of total length; trailing edges of dorsal fins denticulate, without bare ceratotrichia; first dorsal somewhat falcate, with posterior margin abruptly vertical from apex, its midbase about equidistant between pectoral and pelvic bases; pectoral fins moderate-sized, length of anterior margins 12 to 14% of total length, width of posterior margin 8.3 to 11% of total length; pelvic fins moderately large, anterior margin length 6.8 to 8.4% of total length; anal height 2.7 to 3.4% of total length; anal caudal space greater than second dorsal height, 6.1 to 8.1% of total length; ventral caudal lobe more or less falcate in adults. Crowns of lateral trunk denticles lanceolate or weakly tricuspidate, with longitudinal ridges extending their entire length. Skeleton not hypercalcified in adults, except for slight expansion of scapulocoracoid tips; palatine processes of palatoquadrates subdivides at symphysis, with a short separate medial segment on each side; monospondylous precaudal centra 29 to 35, diplospondylous precaudal centra 40 to 48, precaudal centra 73 to 80. Colour uniform grey or grey-brown, above, light below, no white or dark spots or dark bars. Development viviparous. Size moderate, adults 65 to 101 cm.

Distribution
Northwest Pacific: Japan, Korea, China, Taiwan, and Viet Nam [517]. Possibly occurring in the Philippines [544]. Source: www.gbif.org

Human uses
fisheries: commercial

Biology
Viviparous with a yolk-sac placenta. Produces 5 to 16 young per litter, with larger adults having larger litters of young. Gestation period is 10 months, birth occurring in April and May. Size at birth about 28 cm [517]. An inshore bottom-dwelling shark found down to at least 51 m. Probably feeds on benthic invertebrates, especially crustaceans [517][17641] A carnivore [17641].

Size / Weight / Age
87.0 cm TL (male/unsexed; [517]); 101 cm TL (female); max. reported age: 9 years (Ref. 6983)

Habitat
demersal; marine; depth range ? - 300 m [20042]

Remarks
shark-references Species-ID=3794;

Parasites (arranged by Jürgen Pollerspöck)
Cestoda

• Calliobothrium shirozame Kurashima, Shimizu, Mano, Ogawa & Fujita, 2014 [20940]
• Erudituncus xiamenensis (Wang & Yang, 2001) [16436] [7384]

Trematoda

• Stephanostomum ditrematis (Yamaguti, 1939) Manter, 1947 [32542]

Nematoda

• Acanthocheilus rotundatus (Rudolphi, 1819) [19877]
• Mooleptus rabuka (Machida, Ogawa & Okiyama, 1982) [19877]

Copepoda

• Eudactylina musteli Izawa, 2011 [14349]
• Kroyeria elongata Pillai, 1967 [14329] [14328]
• Kroyeria lineata Van Beneden, 1853 [14329]
• Pseudopandarus gracilis Kirtisinghe, 1950 [14327]