Bythinella cf. Bythinella simoniana (Moquin-Tandon, 1856)
Synonym: guranensis (Paladilhe, 1870). Boeters & Falkner redescribed the species in Heldia Bd.5 (4/5) München 2008, p.120: « The shell is stocky to elongated conical with 4¼ to 4¾ whorls. Of these, only the first ones are moderately curved, while from the penultimate whorl towards the mouth a shoulder is formed under the solid suture, from which the wall descends almost flat and is not curved until the next suture. As a result, the slightly sloping oval mouth is a little flattened at the angle of the mouth in frontal view. In lateral view, the edge of the mouth is tilted vertically. The last whorl has several flat ribs (varicose veins), which become more pronounced towards the mouth. These ribs are not just hollow bathtub-shaped bulges, but rather thickened bulges in the shell wall, which correspond to flattened valleys in the inside of the shell due to the thickening. »
Specimen collected in sediment near the porch of Aliou cave river, at Cazavet, Ariège. 3mm. Altitude ≈ 470m.
The growth marks seem slightly more prosocline than in the other species of the area. Notice the presence of occasional longitudinal thickenings, a feature that appears on the shell of Prié & Bichain’s Bythinella navacellensis, and which is said to be noticed also on simoniana. Another feature that was also noticed in simoniana: the subsutural ramp can be almost horizontal in the adult whorls. – Same spot. 2,95-3,10-3,25mm.
An Islamia lives also in the tunnel.
Specimen, possibly belonging to the same species, collected at the emergence. 2,7mm.
The juvenile are umbilicate. The reflected columellar labrum progressively hides the navel, which remains in adult shells only visible as a narrow slit.
Possible specimen collected in sediments, immediately beneath the Moulo de Jaur, a karst spring located on the northern side of Lachein brook, at the base of Sainte Catherine hill, downstream the confluence with Lasquert brook, southern Balaguères, Ariège. 2,7mm. Altitude ≈ 530m.
In sediments, 5m above the average water level, at about 55m deep in the Gouffre de la Peyrère, southern Balaguères. 2,75-3,15mm. Altitude inside the cave ≈ 505m.
H. Brustel legit (FR).
Variations in specimens collected at Las Hountas emergence. Altitude ≈ 500m.
Some of these shells match the description of simoniana engomerica Bœters & Falkner, 2008, a group that was named after the locality of Engomer, downstream Las Hountas in the valley.