Videna castra (Benson, 1852)
“This shell, approaching in form to H. cyathus, Pfr., figured in the 'Conchologia Iconica' at no. 139, bears much resemblance to the Javanese species H. zollingeri of the same author, represented in ‘Conchologia Iconica’ at no. 605, but differs in sculpture, marginate suture, less obtuse spire, and colour.” (Benson, 1852)
“The shell is subject to a very considerable amount of variation as regards the elevation of the spire. Young specimens are sometimes almost planorbular, and in some adults the total height of the shell is scarcely more than one-third of the larger diameter, while in others it somewhat exceeds one half of the same dimension. The width of the umbilicus varies from 0.2 to 0.3 of the diameter of the shell. The base is always distinctly spirally striated, but on the upper side the oblique transverse striae of growth prevail. The usual colour is pale horny, sometimes brown with a pale band below the suture.” (Stoliczka, 1873)
Benson (1852) original descriptions on Helix castra – “Testa mediocriter umbilicata, depressissimo-conica, tenui, exiliter oblique acuto-striatula, cornea; spira ad apicem obtusa, suturis marginatis. Aufractibus 5½ planulatis, ultimo ad periphaeriam acutissime carinato, subtus planiusculo; apertura oblique subquadrata, margine acuto.”
“The animal from dark leaden to blackish grey, being always paler at the sides of the foot, generally tinged with brownish below the pedal row; tentacles and pedicles mostly somewhat darker than the body; neck distinctly warty; sole dark grey, entire, without any distinct furrows; tail gland represented by a fine slit about one mill. long. The total length of the foot generally equals one and a half diameters of the shell, the caudal portion being always shorter than the anterior one. The mantle is blackish and in its extent above the large pulmonary cavity variegated with pale spots.” (Stoliczka, 1873)
“The jaw is smooth, very thin, almost semicircular, with broad oblique ends and a small, in younger specimens sometimes almost obsolete, projection in the centre of the concave edge; its width is about one half millimetre. The radula is narrow, about two mill. long, or slightly longer, composed of about 85 transverse straight rows, there being about 101 teeth in each of them. All have very sharp, long and pointed cusps, the central with a small denticle on either side near tip; on the outer ones, as they turn laterally and gradually decrease in size, the inner denticle disappears, while the outer increases, until on the last 15 or 20 teeth, preceding the 3 or 4 terminal ones, it equals the principal cusp. The last few teeth are short, broad, and their outer cusp becomes almost entirely obsolete, the teeth presenting merely an oblique sharp edge.” (Stoliczka, 1873)
“The female portion of the genital organs has a globular swelling near its origin at the hermaphrodite opening, and the receptaculum seminis branches off above this gland, it is fully one inch long, somewhat thickened in the middle. The penis is attached by a short muscle, about 4 mm long and moderately thickened.” (Stoliczka, 1873)
“There are no important differences from material of S. castra taken at Cherrapoonjee, Assam (FMNH 43601) and identified by Gude. The single adult is 11.5 mm. in diameter, 5.7 mm. high, D/U ratio 4.00, with 6 1/8 whorls. It is questionable if the one species ranges from Sikkim to Malaya an this Thailand shell may belong to a trochomorphid genus. No Sikkimese examples were available and I have accepted Gude’s identification.” (Solem, 1966)
Helix castra – “Diam. major 12, minor 10½, axis 4 mill.” (Benson, 1852); Trochomorpha castra – “larger diam. 13, smaller diam. 12, height of shell 7, same of apert: 3, width of same 5.4 mm.” (Stoliczka, 1873)
Type locality – “Darjiling” leg. R. Trotter (Benson, 1852)
Other localities – “Penang Hill” (Stolizcka, 1873); “Salanga” (Martens, 1883); “G. Tchöra, près Ipoh (Kinta)” (Morgan, 1885); “Kwala Aring, State of kelantan” (Collinge, 1902); “Thailand; Chieng Dao at 1,800 meters” (Solem, 1966)