Eostrobilops hirasei
Encyclopedia
Eostrobilops hirasei is a species
of air-breathing land snail
, terrestrial
pulmonate gastropod mollusks in the family Strobilopsidae
.
The specific name is apparently in honor of Japanese malacologist either of Yoichiro Hirase
(1859–1925) or of his son Shintaro Hirase
(1884–1939).
in 1908. Type specimens are stored in Academy of Natural Sciences
(number 95251) and in Hirase
's collection (number 1538). It was moved into newly created genus Eostrobilops
by Henry Augustus Pilsbry in 1927 and Eostrobilops hirasei is the type species
of the genus Eostrobilops.
is rather depressed, with dome-shaped spire
, the periphery mainly rounded but indistinctly subangular in front of the aperture
, the base rather strongly convex. The umbilicus is small, widened in the last half-whorl, contained about 5½ times in the diameter of shell (in some examples smaller, 6 times or 7½ times in diameter). Opaque, cinnamon-brown,
without much gloss, smoothish, with low growth-wrinkles. Whorls
are strongly convex and increase slowly. The aperture is oblique and lunate, peristome russet, expanded and well thickened. The parietal callus is moderately heavy. The parietal lamella is rather strong and emerges to the edge of the callus. The infraparietal lamella is relatively strong though much lower than the parietal, and emerges nearly to the edge of the parietal callus. Both lamellae penetrate inward about one-third of a whorl, being conspicuously nodose at the edges, and there is a very weak continuation to about half a whorl inward. At a point about one-fourth of a whorl inward there is a low, short and blunt columellar lamella and two short basal folds. All or part of these are visible in an oblique view in the aperture, but owing to the opaque texture of the shell they are not visible through the base in specimens examined.
The height of the shell is 2.1 mm. The width of the shell is 3 mm. The shell has 5⅓ whorls.
The height of the shell of the type specimen is 2.2 mm. The width of the type specimen is 3.2 mm. The type specimen has 5½ whorls.
This relatively large, solid species and it is distinguished from the Eostrobilops coreana and the Eostrobilops nipponica
by the number of internal basal plicae (two). The growth wrinkles or striae are rather fine and somewhat sharp below the suture, but are not regular in development in the peripheral and basal parts.
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 air-breathing land snail
Land snail
A land snail is any of the many species of snail that live on land, as opposed to those that live in salt water and fresh water. Land snails are terrestrial gastropod mollusks that have shells, It is not always an easy matter to say which species are terrestrial, because some are more or less...
, terrestrial
Terrestrial animal
Terrestrial animals are animals that live predominantly or entirely on land , as compared with aquatic animals, which live predominantly or entirely in the water , or amphibians, which rely on a combination of aquatic and terrestrial habitats...
pulmonate gastropod mollusks in the family Strobilopsidae
Strobilopsidae
Strobilopsidae is a family of air-breathing land snails, terrestrial pulmonate gastropod mollusks in the superfamily Pupilloidea.- Taxonomy :...
.
The specific name is apparently in honor of Japanese malacologist either of Yoichiro Hirase
Yoichirō Hirase
was a Japanese malacologist. His son, Shintarō Hirase, was also a malacologist.Majority of his valuable collection of molluscs have been destroyed during the World War II.- Bibliography :* . 貝類手引草 .- External links :* at Internet Archive...
(1859–1925) or of his son Shintaro Hirase
Shintarō Hirase
was a Japanese malacologist. His father, Yoichirō Hirase, was also a malacologist.Shintarō Hirase was a teaching zoologist at Seikei College.- Collection :...
(1884–1939).
Taxonomy
Eostrobilops hirasei was discovered and described under name Strobilops hirasei by an American malacologist Henry Augustus PilsbryHenry Augustus Pilsbry
Henry Augustus Pilsbry was an American biologist, malacologist and carcinologist, among other areas of study. He was a dominant presence in many fields of invertebrate taxonomy for the better part of a century...
in 1908. Type specimens are stored in Academy of Natural Sciences
Academy of Natural Sciences
The Academy of Natural Sciences of Drexel University, formerly Academy of Natural Sciences of Philadelphia, is the oldest natural science research institution and museum in the New World...
(number 95251) and in Hirase
Hirase
Hirase is a Japanese surname.* Mayumi Hirase , a Japanese professional golfer* Shintarō Hirase , a Japanese malacologist. His father was Yoichirō Hirase.* Tomoyuki Hirase , a Japanese former footballer...
's collection (number 1538). It was moved into newly created genus Eostrobilops
Eostrobilops
Eostrobilops is a genus of air-breathing land snails, terrestrial pulmonate gastropod mollusks in the family Strobilopsidae.- Species :The genus Eostrobilops includes the following species:* Eostrobilops coreana Pilsbry, 1927...
by Henry Augustus Pilsbry in 1927 and Eostrobilops hirasei is the type species
Type species
In biological nomenclature, a type species is both a concept and a practical system which is used in the classification and nomenclature of animals and plants. The value of a "type species" lies in the fact that it makes clear what is meant by a particular genus name. A type species is the species...
of the genus Eostrobilops.
Shell description
The shellGastropod shell
The gastropod shell is a shell which is part of the body of a gastropod or snail, one kind of mollusc. The gastropod shell is an external skeleton or exoskeleton, which serves not only for muscle attachment, but also for protection from predators and from mechanical damage...
is rather depressed, with dome-shaped 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...
, the periphery mainly rounded but indistinctly subangular in front of the aperture
Aperture (mollusc)
The aperture is an opening in certain kinds of mollusc shells: it is the main opening of the shell, where part of the body of the animal emerges for locomotion, feeding, etc....
, the base rather strongly convex. The umbilicus is small, widened in the last half-whorl, contained about 5½ times in the diameter of shell (in some examples smaller, 6 times or 7½ times in diameter). Opaque, cinnamon-brown,
without much gloss, smoothish, with low growth-wrinkles. Whorls
Whorl (mollusc)
A whorl is a single, complete 360° revolution or turn in the spiral growth of a mollusc shell. A spiral configuration of the shell is found in of numerous gastropods, but it is also found in shelled cephalopods including Nautilus, Spirula and the large extinct subclass of cephalopods known as the...
are strongly convex and increase slowly. The aperture is oblique and lunate, peristome russet, expanded and well thickened. The parietal callus is moderately heavy. The parietal lamella is rather strong and emerges to the edge of the callus. The infraparietal lamella is relatively strong though much lower than the parietal, and emerges nearly to the edge of the parietal callus. Both lamellae penetrate inward about one-third of a whorl, being conspicuously nodose at the edges, and there is a very weak continuation to about half a whorl inward. At a point about one-fourth of a whorl inward there is a low, short and blunt columellar lamella and two short basal folds. All or part of these are visible in an oblique view in the aperture, but owing to the opaque texture of the shell they are not visible through the base in specimens examined.
The height of the shell is 2.1 mm. The width of the shell is 3 mm. The shell has 5⅓ whorls.
The height of the shell of the type specimen is 2.2 mm. The width of the type specimen is 3.2 mm. The type specimen has 5½ whorls.
This relatively large, solid species and it is distinguished from the Eostrobilops coreana and the Eostrobilops nipponica
Eostrobilops nipponica
Eostrobilops nipponica is a species of air-breathing land snail, terrestrial pulmonate gastropod mollusks in the family Strobilopsidae.- Subspecies :* Eostrobilops nipponica nipponica Pilsbry, 1927 - It is vulnerable subspecies....
by the number of internal basal plicae (two). The growth wrinkles or striae are rather fine and somewhat sharp below the suture, but are not regular in development in the peripheral and basal parts.