Allopeas gracile (Hutton, 1834)
“M. Dautzenberg states that Hutton described this species without specific name in 1834; but Hutton on p. 93 of his paper gives a table of the names, expressly indicating those he had named. This species, including 0. subula which I agree with Boettger is not separable from gracile, has a wide range in the tropics of both hemispheres. In the Old World it is especially characteristic of the Oriental Region of Wallace, but passes beyond into Polynesia, and in the northeast reaches to Japan, which has an Oriental land-snail fauna. Westward it reaches Aden, probably Abyssinia, British East Africa and the Mascarene Is.” (Pilsbry, 1906)
“The series before me from Mauritius, Ceylon, India, China, the Philippines, etc., shows but little variation except in size. Specimens from Okinawa, Ryukyu, have slightly more convex whorls, the striation is a trifle weaker and they are more glossy (pl. 18, fig. 6), the one figured measuring 12.8 x 3.5 mm., with 8½ whorls. Further north 0. gracile has been found by Mr. Hirase in Kyushu, Hondo and even as far as Kayabe, Ojima, in the island of Yesso further north than any other species of the genus. A shell from this place measures 11.3 x 3 mm., with 9 whorls. It has been found by Mr. Hirase's collector on Kita-iwojima, one of the Sulphur group, near the Bonin Islands, and on Hahajima, Ogasawara (Bonin Is.); the form occurring there (pl. 22, fig. 10) being small, 8 mm. long, with 7 whorls, the suture subtly crenulate in places. It is thin and delicate, as might be expected on volcanic soil.” (Pilsbry, 1906)
“The Chinese Bul. fortunei Pfr. and "B. scalaris Desh." have been considered synomyms of 0. subula Pfr. by Gredler. The former is placed in the synomyms of Bul. decorticatus Reeve by von Martens. I have not the material for deciding this question. Bulimus cereus Reeve (pl. 18, fig. 7) was based on an Indian specimen of gracile. The following form (Opeas apex nicobarica) from the Nicobar Islands is apparently synonymous.” (Pilsbry, 1906)
“In Mauritius (pl. 23, fig. 23) the shells do not reach so large a size as in Ceylon, etc., but are otherwise practically typical. A series collected by Sir Charles Eliot at Takaungu, on the coast of British East Africa in lat. 3 42' south (pl. 23, figs. 24, 25) also fall short of the maximum size, the two figured measuring 10 x 3 and 8 x 2.6 mm., both with 7¼ whorls, the suture crenulate in the upper half of the shell's length.” (Pilsbry, 1906)
“The original description and figures of 0. souverbianum (pl 24, fig. 31) and of 0. artense (pl 24, fig. 32) are given below. These seem to me to pertain to the more obese and more slender phases respectively of one and the same species, which I am unable to distinguish from 0. gracile. E. L. Layard, of Noumea, the wellknown collector of New Caledonian shells, "maintained that there was no difference between S. souverbiei, S. artensis, S. tuckeri and the Ceylon species," the latter being 0. gracile (P. Z. S. 1888, p. 358). The specimens before me from Noumea, Art Island and He Casy, received from G. Dupuy and E. Marie, support the reference to 0. gracile. They are however a small form, not reaching the dimensions of typical 0. gracile. Shells from Noumea (pl. 24, figs. 40, 41, slender phase) measure 8.8x2.8 and 8.8x2.2 mm., with 73,4 and 8 whorls. The stride are stronger below the somewhat crenulated suture, as usual.” (Pilsbry, 1906)
“In Polynesia I have seen forms of 0. gracile from the Viti, Samoan and Society groups, and from Washington (or New York) island. It has been reported from Funafuti, the Marshall and the Caroline Islands. The shells before me are all smaller than typical gracile. In most of them the suture is finely but distinctly denticulate in places, chiefly in the upper half of the shell. I have figured a shell from Tahiti, pl. 22, fig. 4, nine mm. long with over 7 whorls and nearly smooth suture, and a more slender Samoan shell, pl. 22, fig. 11, received from Schmeltz as "upolensis Mouss." It is 8.8 mm. long, with 7 ½ whorls.” (Pilsbry, 1906)
Bulimus junceus – “This shell very closely resembles a West Indian species, and is, perhaps, the same, and may be a denizen of the cocoanut or banana, wherever found. B. bacterionides agrees in form, but this is not 'smoother than octona,' and has not nine whorls.” (Gould, 1846)
Bulimus artensis - “Cette espèce diffère du B. souverbianus, Gassies, par la forme plus élancée de sa spire, ses tours plus nombreux et plus saillants, son ouverture plus allongée et ses stries à peine visibles à la loupe.” (Gassies, 1866)
Opeas apex nicobarica - “L'Opeas apex de Java diffère du nôtre par son épiderme plus épais, sa columelle plus élargie et son ombilic moins étroit.” (Mörch, 1872); “Opeas apex of Java differs by its thicker epidermis, its wider columella pnd less narrow umbilicus.” (Pilsbry, 1902 after Morch, 1872)
“Bulimus junceus Old. was based upon the small Polynesian race of gracile.” (Pilsbry, 1906)
“Opeas gracile is a very variable species, slender and bulky, ribbed and smooth, weakly and strongly sutured shell occurring. This has given rise to a multitude of different names. Opeas curvicosta Moellendorff is an O. gracile in which the vertical ribs are distinctly developed. Moreover it has more “shouldered” whorls than in normal specimens. The type shell, a unique specimen, was collected in the Djampangs, West Java, at 2000 feet by H. Fruhstorfer in 1893 (Museum Senckenberg, no. 63910). When quite young the shell was severely damaged, as can be seen from an oblique crack reaching from was severely damaged, as can be seen from an oblique crack reaching from the 1 ½ to the second whorl. This may explain the somewhat irregular further growth. Nevertheless the shell attained a size of 7 mm height, 2 ½ mm with and an aperture of 2.25 mm height.” (Benthem-Jutting, 1952)
Gould (1846) original descriptions on Bulimus junceus – “Shell small, thin, translucid, elongated, turreted, of a pale green color, obtuse at apex, covered with delicate longitudinal strise. Whorls seven, slightly convex, presenting a broad shoulder above. Aperture long ovate: lip simple, on the left slightly reflected over a minute umbilical chink: the last whorl a-bout one-third the length of the whole shell.”
Gassies (1866) original descriptions on Bulimus artensis – “Testa imperforata, turbinata, elongatula, corneo-pallida, tenuis, diaphana, nitida, longitudinaliter tenuiter striata; anfractus 7-8 regulariter accrescentes, ultimus 1/3 longitudinis formans; sutura profunda, intrante; apertura ovato-elongata; columella arcuata, vix callosa; peristoma simplex, acutum.”
Mörch (1872) original descriptions on Opeas apex nicobarica – “T. anguste turrita, extus cerea, intus lactea; anfr. 7½ sat convexi, anfr. primi 3 laevigati, flavi, caeteri irregulares, costulato-striati; costulae obsolete sigmoideae, proesertim in anfr. ultimo; lineis spiralibus obsoletissimis sed in basi fortioribus; sutura profunda, subcrenata, proesertim distinctior in anfr. medianis; apertura subelliptica, antice admodum angustata, labio reflexo medio plica munito obsoletissima; rima punctiformi.”
Pilsbry (1906) translations on Gassies’s Bulimus souverbianus – “Shell turbinate, elongate, not umbilicate, pellucid-buff, fragile, diaphanous, longitudinally delicately increasing, the last half the total length; suture deep. Aperture ovate-elongate; columella slightly calloused, peristome simple.”
Pilsbry (1906) translations on Gassies’s Bulimus artensis – “Shell imperforate, turbinate, rather lengthened, pale corneous, thin, diaphanous, glossy, longitudinally delicately striate. Whorls 7 to 8, slightly convex, regularly increasing, the last forming onethird the total length; suture deep, apex rather obtuse. Aperture ovate-elongate, columella arcuate, slightly calloused; peristome simple, acute.”
Pilsbry (1906) translations on Morch’s Opeas apex nicobarica – “Shell narrowly turrited, waxen outside, white within, with 7½ quite convex whorls, the first two smooth, yellow, the rest irregular, costulate-striate, the riblets obsoletely sigmoid, especially on the last whorl, and with very obsolete spiral lines, stronger on the base. Suture deep, subcrenate, more distinctly so in the middle whorls. Aperture subelliptical, somewhat narrow anteriorly, inner lip reflexed, with a very obsolete fold in the middle; rimation punctiform.”
Pilsbry (1906) descriptions on Opeas gracile from Ahmednuggur – “It is perforate, slender, and regularly, straightly tapering to the small, obtuse apex, pale-yellowish corneous, without much gloss. The moderately and regularly convex whorls are very distinctly, arcuately striate. The suture is usually a trifle irregular, and often quite distinctly crenulate, and the surface below it is more or less distinctly puckered. The aperture is long, rhombic-ovate, and the columellar margin is widely reflexed.”
Benthem-Jutting (1952) description on Opeas gracile – “Shell high-turreted, with numerous whorls. Pale yellowish-white or straw colour. Fragile, hyaline, with a soft silky lustre. Vertical striation distinct, sometimes even delicately ribbed; spiral striae very weak. Whorls 7 to 8, regularly increasing in size. Well rounded, although less so than in Opeas clavulinum. Suture distinct, indictinctly margined. In coarsely striated shells the suture is finely crenulated. Last whorl less than one-third of the entire shell-length. Top pointed, base round. Umbilicus hair-like in immature shells, closed in adult ones. Aperture vertical, or a little oblique. More or less oval, longer than broad, pointed above and rounded below. Peristome not continuous. Exterior margin not thickened or reflected. Columellar margin slightly reflected.”
Bulimus junceus – “Length of axis three-tenths of an inch; breadth one-tenth of an inch.” (Gould, 1846); Bulimus artensis – “Long. 9 mill., diam. 2 mill.” (Gassies, 1866); Opeas apex nicobarica – “Long. 9 mill.; lat. 2½ mill.; aperturae long. 2½ mill.” (Mörch, 1872); Bulimus souverbianus – “Length 7, diam. 2.5 mm.” (Pilsbry, 1906 after Gassies, 1859); Bulimus artensis – “Length 9, diam. 2 mm.” (Pilsbry, 1906 after Gassies, 1866); Opeas apex nicobarica – “Length 9, diam. 2.5, aperture 2.5 mm. long” (Pilsbry, 1906 after Morch, 1872); Opeas gracile from Ahmednuggur – “Length 12-13, diam. 3.1-3.5, aperture 3.7-3.8 mm., whorls 8½-9. These shells (pl. 18, figs. 3-5) illustrate the slender and stouter phases of the species, usually to be found in any large lot from one place.” (Pilsbry, 1906); Opeas gracile – “Dimensions: Height 9 to 10 mm, width 3 and 3½ mm, height of aperture 3 mm” (Benthem-Jutting, 1952)
Type locality - Bulimus junceus “Tahiti and Eimeo” (Gould, 1846); Bulimus souverbianus “insula Art, Novoe Caledoniae” leg. M. Montrouzier (Gassies, 1859); Bulimus artensis “insula Art, Novoe Caledoniae” leg. M. Montrouzier (Gassies, 1866); Opeas apex nicobarica “Nancouri” leg. Kjellerup (Mörch, 1872)
Other localities – “Salanga” (Martens, 1883); “P. Pinang” (Morgan, 1885); “Mittel-Sumatra: Hohle von Pauh bei Fort de Kock” (Rensch, 1934); “Bali: Trockental bei Kintamai (1300 m)” (Rensch, 1934); “Thailand; Chieng Dao” (Solem, 1966)
Distributions – “India, Ceylon and the East Indies, China, Formosa and Japan, etc.; Mascarene Islands; Polynesia.” (Pilsbry, 1906); “Hindoustan, Seychelles, Sumatra, Java, Siam, Birmanie, Pegou” (Morgan, 1885); “In viele Tropenlander verschleppt, Auf dem Sundabogen von Sumatra bis Timorlaut” (Rensch, 1934)
“Living on the ground, in the woods of the hills and mountains, between 700 and 2958 m.” (Benthem-Jutting, 1952)