Afrodonta mystica Herbert 2020, sp. nov.
Creators: name: Herbert, David G.
Publisher: name: Zenodo
Year: 2020
Subjects: Biodiversity
Taxonomy
Animalia
Mollusca
Gastropoda
Stylommatophora
Charopidae
Afrodonta
Afrodonta mystica

description: Afrodonta mystica sp. nov.
urn:lsid:zoobank.org:act: 95482B02-41BA-4129-A4B1-32DD8DF1D095
Figs 4 G–J, 6, 17M–N
Diagnosis
Shell very small, spire slightly raised; protoconch microscopically shagreened or malleate; teleoconch surface silky; sculpture of simple, close-set, microscopic axial riblets; aperture with a well-developed, crescentic, in-running parietal lamella and a strong baso-columellar denticle; palatal region with a strong, deeply recessed, ridge-like denticle just above mid-whorl, plus a broad, thickened pad below mid-whorl, opposite and below parietal lamella; umbilicus relatively narrow. Shell corneous-brown to yellowish-brown when fresh; diameter up to 1.2 mm.
Etymology
From the Greek mystikos (μυστΙΚός): a mystery, mysterious; with reference to the environs of Nkandla – long considered a region of mystery in Zulu folklore and to this day a place of secrecy, subterfuge and skulduggery.
Material examined
Holotype SOUTH AFRICA • KwaZulu-Natal, Nkandla Forest; 28.733° S, 31.133° E; 900 m a.s.l.; 10 Aug. 1997; D.G. Herbert leg.; mistbelt Podocarpus forest, in leaf-litter; diameter 1.16 mm, height 0.61 mm; NMSA V4993/T4237.
Paratypes SOUTH AFRICA • 3 specimens; same collection data as for holotype; NMSA P1009/T4238.
Description
Shell very small, diameter up to 1.2 mm, H/D ratio ±0.53; spire slightly raised; suture indented and apical portion of whorls strongly convex, whorls thus weakly shouldered; periphery more or less at mid-whorl, evenly rounded; last adult whorl slightly descendant. Protoconch comprising apical cap plus approx. 0.75 whorl; diameter ±310 μm; microscopically shagreened or malleate. Teleoconch of up to 2.75 whorls; surface texture silky; sculpture of simple, close-set, microscopic axial riblets; riblets alternating in strength and with even finer spiral threads in their intervals. Umbilicus relatively narrow. Aperture obliquely lunate; parietal region with a well-developed, crescentic, in-running lamella situated well below mid-whorl, extending just beyond edge of aperture, its interior end with a distinct downward deflection; baso-columellar region with a strong denticle (shape somewhat variable); palatal region with a strong, deeply recessed, ridge-like denticle just above mid-whorl, its crest thickened, plus a broad, thickened pad below mid-whorl, opposite and below parietal lamella. Shell corneous-brown to yellowish-brown when fresh.
Distribution and conservation
A narrow-range endemic (Fig. 6), known only from Nkandla Forest, KwaZulu-Natal, at approx. 900 m a.s.l.; living in leaf-litter of transitional mistbelt/scarp forest. This forest is formally protected and under the care of the provincial conservation authority, Ezemvelo KwaZulu-Natal Wildlife.
Remarks
The only other species with a single parietal lamella, Afrodonta bilamellaris and Af. unilamellaris, lack palatal dentition.
description: Published as part of Herbert, David G., 2020, Revision of the aperturally dentate Charopidae (Gastropoda: Stylommatophora) of southern Africa - genus Afrodonta s. lat., with description of five new genera, twelve new species and one new subspecies, pp. 1-55 in European Journal of Taxonomy 629 on pages 15-16, DOI: 10.5852/ejt.2020.629, http://zenodo.org/record/3762280