Closing apparatus of Clausiliidae

The closing apparatus (clausiliar), which presents many characters of taxonomic importance, consists of the following parts:

1. Plicae of the parieto-columellar side = lamellae:

superior lamella (parietalis, sul) and spiral lamella (spiralis, spl)
inferior lamella (columellaris, il), subcolumellar lamella (subcolumellaris, scl)
clausilium, consisting of stalk (cs) and plate (cp).
The space between superior lamella and inferior lamella is named interlamellar.
Near to the suture a parallel lamella (parallelis, pll) is often present.

2. Plicae of the palatal side = plicae (in the strict sense):

principal plica (principalis, pri),
palatal plicae (lunellar): upper palatal plica (up), if lunella present, with anterior part (upa) and posterior part (upp),
middle palatal plicae resp. lunella (lun), lower palatal plica (lp), if lunella present, with anterior part (basalis, bas) and posterior part (subclaustralis, scs), lowest palatal plica (sulcalis, sulc).
If subclaustralis and sulcalis are fused or indistinguishable only the term posterior lower palatal plica should be used.
Near to the suture a sutural plica (suturalis, sut) is often present.
The callous thickening of the palatal wall behind the peristome is named palatal callus.

Genitalia of Clausiliidae

The end genitalia of Clausiliidae are of great taxonomic importance. They consist of the following parts:

ad = allospermiduct, od = oviduct, pr = prostate.

Female copulatory organs:
bb = bursa of bursa copulatrix, db = diverticulum of bursa copulatrix, fod =
free oviduct, pb = pedunculus of bursa copulatrix, = vagina.

Male copulatory organs:
ep = epiphallus, fl = flagellum, p = penis, pc = penial caecum, rp = penial retractor, vd = vas deferens.

Genital atrium:
at = atrium.

End genitalia of Clausiliidae (plesiomorphic state, schematized)