The shell has a typical trochoid shape with a spire angle of approximately 72 degrees and nearly smooth sided until the body whorls which are slightly inflated at the shoulder with a rounded periphery. The base is moderately convex to flat, and the shell has a large nacreous (pearly) columellar callus which covers about one third of the base and can be keeled at its outer margin. The aperture is oval, the slit is positioned mid whorl and is long, about 16 to 20 percent of the circumference. The shell is heavily textured with about 20 spiral cords crossed by numerous fine crescent shaped axial growth lines above the selenizone (the area where the shell growth filled in the slit) and about 10 spiral cords below.
The shell is creamy yellow overlaid with many crimson axial flammules above and below the selenizone which has yellowish orange crescent shaped growth marks, the base is a pale creamy yellow with occasional light crimson flammules, and the interior of the aperture is nacreous. The shell is occasionally found with part of its dark brown periostracum near the margin opposite the aperture. The operculum is small, dark brown, multispiral, and chitinous. Size range: 45 to 129 mm diameter.[2][3]
^ abAnseeuw, P. & Goto, Y., The Living Pleurotomariidae (1996), Elle Scientific Publications, Osaka Japan, pp. 202, at pp. 98-99.
^Original description: Henry A. Pilsbry, in Proceedings of the Academy of Natural Sciences of Philadelphia, USA (1903) Vol. 55, "Pleurotomaria hirisei, n. sp."
External linksedit
Wikimedia Commons has media related to Mikadotrochus hirasei.
"Mikadotrochus hirasei hirasei". Gastropods.com. Retrieved 16 January 2019.
This Pleurotomariidae-related article is a stub. You can help Wikipedia by expanding it.
mikadotrochus, hirasei, common, name, emperor, slit, shell, species, large, deepwater, snail, marine, gastropod, mollusk, family, pleurotomariidae, slit, snails, five, views, shell, scientific, classificationkingdom, animaliaphylum, molluscaclass, gastropoda, . Mikadotrochus hirasei common name the emperor s slit shell is a species of large deepwater sea snail a marine gastropod mollusk in the family Pleurotomariidae the slit snails 1 Mikadotrochus hiraseiFive views of a shell of Mikadotrochus hiraseiScientific classificationKingdom AnimaliaPhylum MolluscaClass Gastropoda unranked clade VetigastropodaSuperfamily PleurotomarioideaFamily PleurotomariidaeGenus MikadotrochusSpecies M hiraseiBinomial nameMikadotrochus hirasei Pilsbry 1903 SynonymsMikadotrochus hirasei yamamotoi Yamamoto 1993 Perotrochus hirasei Pilsbry 1903 Pleurotomaria hirasei Pilsbry 1903Shell of Mikadotrochus hirasei Pilsbry 1903 measuring 55 7 mm height by 68 6 mm width trawled at 300 ft in Japan Contents 1 Description 2 Distribution 3 References 4 External linksDescription editThe shell has a typical trochoid shape with a spire angle of approximately 72 degrees and nearly smooth sided until the body whorls which are slightly inflated at the shoulder with a rounded periphery The base is moderately convex to flat and the shell has a large nacreous pearly columellar callus which covers about one third of the base and can be keeled at its outer margin The aperture is oval the slit is positioned mid whorl and is long about 16 to 20 percent of the circumference The shell is heavily textured with about 20 spiral cords crossed by numerous fine crescent shaped axial growth lines above the selenizone the area where the shell growth filled in the slit and about 10 spiral cords below The shell is creamy yellow overlaid with many crimson axial flammules above and below the selenizone which has yellowish orange crescent shaped growth marks the base is a pale creamy yellow with occasional light crimson flammules and the interior of the aperture is nacreous The shell is occasionally found with part of its dark brown periostracum near the margin opposite the aperture The operculum is small dark brown multispiral and chitinous Size range 45 to 129 mm diameter 2 3 Distribution editThis species is found in deep water between 150 and 300 meters on mud and sand off the coast of the Shima Peninsula in Japan westwards to the Pacific coast of Shikoku Island in the East China Sea west of Kyushu to Taiwan and has also been found in the central Philippines 2 References edit Mikadotrochus hirasei Pilsbry 1903 Retrieved through World Register of Marine Species on 6 November 2011 a b Anseeuw P amp Goto Y The Living Pleurotomariidae 1996 Elle Scientific Publications Osaka Japan pp 202 at pp 98 99 Original description Henry A Pilsbry in Proceedings of the Academy of Natural Sciences of Philadelphia USA 1903 Vol 55 Pleurotomaria hirisei n sp External links edit nbsp Wikimedia Commons has media related to Mikadotrochus hirasei Mikadotrochus hirasei hirasei Gastropods com Retrieved 16 January 2019 This Pleurotomariidae related article is a stub You can help Wikipedia by expanding it vte Retrieved from https en wikipedia org w index php title Mikadotrochus hirasei amp oldid 1192150151, wikipedia, wiki, book, books, library,
