Phaedusa filicostata kapayanensis (de Morgan, 1885)
“Gette coquille ressemble, à première vue, à la Cl. filicostata et à la Cl. penangensis, mais elle se sépare aisément de ces deux espèces par sa forme générale Presque cylindrique, par la position de son ouverture qui est très peu déjetée, ainsi que par l'existence d'une troisième dent au sommet du bord columellaire.” (Morgan, 1885)
“The specimens from the last mentioned locality (Batu caves) are generally larger than those from Perak, still there is in my opinion no reason to distinguish between the two forms. To what extent there is question of an independent development in the same direction in two isolated areas or only of two different localities of the same subspecies, we cannot yet decide. There are too few data to form an opinion. As von Moellendorff stated, the close relationship between Ph. f. kapayanensis and the filicosta form from Perlis, Kedah and Perak (Mount Pondok) is evident. As to the distribution, the area, where subsp. kapayensis is found, lies north and south of that of Ph. filicostata tenuicosta. This is noy very likely for two related subspecies. As they are very closely related they might perhaps better be united. But since it is desirable to obtain more data on eventual differences of the subspecies, it seems best to maintain the names. Subspecies compressa is a broad short form of Ph. filicostata; subsp. kapayanensis is a very long slender form with a small aperture, instead of a strikingly large one.” (Loosjes, 1953)
Morgan (1885) original descriptions on Pseudonenia kapayanensis – “Pseudonenia testa sinistrali, fusca, apertura alba, fusiformi, cylindricea, tenui, angusta, tenuiter striata, fusca, cornea, 13 vel 14 infractibus parum rotundatis, convexiusculis , obliquisque composita, ultimo anfractu coarctato, prope aperturam oblique birugato; sutura lineata; apertura magna, subtriangulata, dentibus 3 ad labrum columellarem ornata; labro reflexo albidoque. Clausilium tenue, mediocriter apertum et inferne acutissimum.”
Morgan (1885) French descriptions on Pseudonenia kapayanensis – “Coquille - Senestre, fragile, fusiforme, cylindroïde, très aiguë au sommet, finement striée parallèlement aux lignes d'accroissement; spire composée de 13 à 14 tours légèrement arrondis, le dernier étant contracté un peu au-dessous de l'ouverture, et fortement plissé; ouverture grande, droite, subtriangulaire; péristome réfléchi, mince, garni de deux forts plis du côté du bord columellaire, et d'une petite dent très peu marquée au-dessus de ces deux plis. Clausilium mince et très fragile, très allongé, non denté, terminé à sa partie externe par un élargissement triangulaire.”
Loosjes (1953) descriptions on Phaedusa filicostata kapayanensis – “Shell of medium size to large, slender distinctly turreted, not very solid, brown to yellowish-brown, dull, scarcely transparent. Spire gradually and slowly broadening, with straight lateral outlines. Whorls 12 ½ to 14 ½. Slightly convex. In a side view the neck is strongly curved down to the base of the aperture. The height of the whorls is steadily increasing from the first top whorl down to the last, in such a way that, measured along the ventral side of the shell, the lower half of the total length enclose the aperture and almost 3 whorls above it. Aperture more or less triangular. The sinulus is only separated from the aperture by the lamella superior. The plane in which the peristome lies is curved slightly backward basally. The aperture is relatively small. From the sinulus the outer peristomal edge descends straight, the parieto-columellar edge is regularly but steeply curved downward. The lamellae show no differences compared with subsp. tenuicosta. The closing apparatus lies usually at the right side. We may not up to ten plicae between the principal plica and the lamella subcolumellaris. The plate of the clausilium has never been described before: it is broad and short, the main curve at 1/3 from the top, there it is broadest too, the sides diverge up to that point in such a way that the plate is almost triangular. The top is slightly thickened. The dimensions of the plate are: length 2.3, width 1.5 mm.”
Pseudonenia kapayanensis – “Dimensions - Longueur, 22 mm; épaisseur, 3½ mm; longueur de l'ouverture, 4 mm.” (Morgan, 1885); Phaedusa filicostata kapayanensis – “Length of the shells: 20.8 to 27.8 mm, diam. 3.5 to 4.7 mm; aperture: height 4.1 to 5.6 mm, width 2.8 to 4.1 mm.” (Loosjes, 1953)
Type locality – “G. Lano, près Campong Kapayan” (Morgan, 1885).
Other localities - “Belimbing, State of Ligeh” (Collinge, 1902); “Selangor: Batu Caves” leg. M. W. F. Tweedie/1932 (Loosjes, 1953); “Mount Besar, west of Patani (Siam)” (Loosjes, 1953); “Mount Rapat, south of Ipoh” (Loosjes, 1953)
“Cette espèce est assez abondante sur le G. Lano, près Campong Kapayan, elle vit sur les troncs d'arbres et au milieu des détritus végétaux avec les Alycaeus et les Aulopoma, le G. Lano est d'ailleurs la seule localité où je l'aie rencontrée.” (Morgan, 1885)
“The habitat of this subspecies is on tree-trunks and on the soil between decaying matter of vegetable origin, at 100 to 600 m altitude.” (Loosjes, 1953)