Benthastelena haliarchus is a species

Species

In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 of sea snail

Sea snail

Sea snail is a common name for those snails that normally live in saltwater, marine gastropod molluscs....

, a marine gastropod mollusk in the family

Family (biology)

In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...

 Calliostomatidae

Calliostomatidae

Calliostomatidae is a family of sea snails within the superfamily Trochoidea and the clade Vetigastropoda.- Description :The Calliostomatidae are unusually diverse. They are characterized by a stepped spire and a pointy aperture. They may possess or lack an umbilicus. The columella is sometimes...

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Description

This species has a fine, top-shaped shell, which is almost triangular in side view, with a sharp basal angle. The tall, flat-sided spire

Spire (mollusc)

A spire is a descriptive term for part of the coiled shell of mollusks. The word is a convenient aid in describing shells, but it does not refer to a very precise part of shell anatomy: the spire consists of all of the whorls except for the body whorl...

 has 9-10 whorls. The shell surface appears smooth, but is encircled by many fine granulated spiral striae. The base is a little inflated. The umbilicus is absent. Color is light brown with darker brown spots or white patterns present on the spiral striae.

Distribution

This species occurs in Southern Hokkaido

Hokkaido

, formerly known as Ezo, Yezo, Yeso, or Yesso, is Japan's second largest island; it is also the largest and northernmost of Japan's 47 prefectural-level subdivisions. The Tsugaru Strait separates Hokkaido from Honshu, although the two islands are connected by the underwater railway Seikan Tunnel...

, Japan

Japan

Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...

 and southwards, at 50 to 200 m depth on fine sand. It is also found off the Oga Peninsula

Oga Peninsula

The Oga Peninsula is a rugged peninsula which projects west into the Sea of Japan from the coast of Akita in northern Honshū, the main island of Japan...

, Japan Sea, and Cheju Island, Korea

Korea

Korea ) is an East Asian geographic region that is currently divided into two separate sovereign states — North Korea and South Korea. Located on the Korean Peninsula, Korea is bordered by the People's Republic of China to the northwest, Russia to the northeast, and is separated from Japan to the...

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