Afrodonta inhluzaniensis inhluzaniensis ( Burnup, 1912 )

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, European Journal of Taxonomy 629, pp. 1-55 : 11-13

Afrodonta inhluzaniensis inhluzaniensis ( Burnup, 1912)

Figs 4 A–C, 5, 17I–J

Endodonta [ Endodonta (Afrodonta) ] inhluzaniensis Burnup, 1912: 342 , pl. 24, figs 14–17.

Endodonta (Afrodonta) inhluzaniensis – Connolly 1912: 128. Afrodonta inhluzaniensis – Connolly 1939: 251, text-fig. 19(5). — Solem 1970: 362. — Herbert & Kilburn 2004: 248, text-fig.

Diagnosis

Shell very small, spire raised; protoconch smooth, at most microscopically shagreened (diameter 320– 350 μm); teleoconch texture silky; sculpture comprising simple, very fine and close-set axial riblets of alternating strength; spiral sculpture of indistinct threads in riblet intervals; parietal region lacking dentition; baso-columellar region typically with a strong, transversely-elongate denticle, its apex rounded or flat; palatal region with a single robust trigonal lamella just below periphery, angled upward and with a thickened crest; shape and strength of denticles somewhat variable; umbilicus relatively narrow. Shell corneous to golden-brown when fresh; diameter up to 1.5 mm.

Material examined

Holotype

SOUTH AFRICA • KwaZulu-Natal, Inhluzani Mountain [Dargle area, Nhlosane]; prior to 1912; H.C. Burnup leg.; NHMUK 1912.3.25.2 .

Paratypes

SOUTH AFRICA • 3 specimens; same collection data as for holotype; NMSA 2607/T614 .

Distribution and conservation

Endemic to eastern South Africa ( Fig. 5 ), ranging widely from the Soutpansberg and Wolkberg in Limpopo, along the Mpumalanga escarpment, and throughout much of the KwaZulu-Natal interior, at altitudes in excess of 1000 m; in leaf-litter of mistbelt and northern afrotemperate forest. Not of conservation concern.

Remarks

Specimens from the northern mistbelt forest in Mpumalanga and Limpopo closely resemble typical specimens from the KwaZulu-Natal interior. They retain a single baso-columellar denticle, but it is less robust than in the typical form and the palatal lamella is slender, strongly trigonal and its crest only slightly thickened. In addition, they rarely attain as large a size as those from KwaZulu-Natal and usually have a proportionately more elevated shell (H/D ratio closer to 0.65 compared with 0.55). Since these differences are relative and exhibit some overlap, I do not consider these northern populations worthy of recognition as a separate entity.

Figures

Fig. 4. Shells of Afrodonta species. A–C. Af. inhluzaniensis inhluzaniensis (Burnup, 1912), Balgowan, KwaZulu-Natal, diameter 1.42 mm (NMSA V7240). D–F. Af. inhluzaniensis leptolamellaris subsp. nov., holotype, diameter 1.2 mm (NMSA V7615/T4235). G–J. Af. mystica sp. nov., holotype, diameter 1.16 mm (NMSA V4993/4237). K–N. Af. novemlamellaris (Burnup, 1912), Somerset East, E. Cape, diameter 1.32 mm (NMSA W752).

Fig. 5. Distribution of Afrodonta inhluzaniensis inhluzaniensis (Burnup, 1912) (orange squares) and Af. inhluzaniensis leptolamellaris subsp. nov. (blue triangles). Contour at 1000 m.