Gyliotrachela depressispira van Benthem Jutting, 1949
“The species is close to Gyliotrachela hungerfordiana (Mollendorff), but it differs in following characters: (1) The spire is lower; 1.6 mm. on max. diam of 3.3 mm. in despressispira against 2.5 mm. on max. diam. of 3.0 mm. in hungerfordiana. (2) The free part of the last whorl ascends vertically (not obliquely as in hungefordiana), the aperture lying in a horizontal plane. (3) The aperture bears more teeth in depressispira.” (Benthem-Jutting, 1949)
Benthem-Jutting (1949) original descriptions on Gyliotrachela depressispira – “Shell very low, conical, almost flat, the 1-1 ½ first whorl projecting only very little from the rest of the spire. Last whorl produced into a trumpet-shaped aperture, free from the spire, first running foreward, afterwards ascending and facing upwards in an almost horizontal plane, sowewhat like Hypselostoma tubiferum (Benson). Dark brown, thin, little transparent, somewhat glossy. Surface minutely granular. Striate according to lines of growth. Sometimes the striae are placed so regularly that they can be mistaken for a pattern of radiate sculpture lines. Whorls 3-4, convex, separated by a much impressed suture. On the last whorl there is a shallow spiral groove about midway between the suture there is a shallow spiral groove about midway between the suture and the periphery, making the keel standing out more prominently. The peripheral keel is continued on the free part of the last whorl and becomes more cord-like towards the aperture. At the base of the shell there runs another well defined keel along the widely open umbilicus. This keel is also continued on the free part of the ultimate whorl like a little raised cord. Together with the peripheral keel these sharp edges render the trumpet more or less quadrangular in aspect. Top a little projecting, mamillar. Aperture indistinctly tetragonal, provided with 17 teeth within, of which four large ones form a cross. All teeth are minutely puckered. Angular and parietal teeth free along their whole extent, although implanted on the same socket. Peristome continuous, very fragile.”
Dimensions: Max. diam. (including peristome) – 3.3-3.9 mm; Min. diam. – 2.1-2.6 mm; Height of shell – 1.5-1.6 mm; Height of shell (incl. aperture) – 1.7-2.2 mm; Height of aperture – 1.4-1.7 mm, (Benthem-Jutting, 1949)
Type locality – “Bukit Chintamani, Pahang” (Benthem-Jutting, 1949)
Other localities – “Gua Bama, near Padang Tengku” leg. Benthem-Jutting/Sep. 1941; “Bukit Panching, near Kuantan” leg. Benthem-Jutting/1947 (Benthem-Jutting, 1949); “Bukit Chintamani” (Berry, 1961); “Kelantan; Batu Pulau Raba, (5°04’15”N, 101°55’35”E)” (Davison & Kiew, 1990); “Kelantan; Gua Panjang, (4°48’00”N, 102°00’00”E)” (Davison & Kiew, 1990)
NCB.naturalis collection RMNH 5541 at Bukit Chintamanis, Pahang, Malaysia.
“Gyliotrachela on the other hand is an air breathing pulmonate, and thus less likely to be affected by dryness and fluctuations in the humidity of the air. During long periods of dryness individuals seal the rim of the aperture to the dry rock surface with mucus and remain immobile. In the laboratory this inactive period has lasted up to 34 days in the case of G. depressispira, when activity commenced on moistening.” (Berry, 1961)
“Regions which were shaded and free of lichen and moss… G. depressispira was found only on bare rock, and never on moss” (Berry, 1961)
“The stomachs of Gyliotrachela usually contained algal cells, often large amounts of lichen, but never fragments of moss.” (Berry, 1961)