Phialodonta introtuberculata ( Connolly, 1933 ) Herbert, 2020

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 : 42-44

publication ID	https://doi.org/ 10.5852/ejt.2020.629
publication LSID	lsid:zoobank.org:pub:ECEBD539-6E3E-45BE-A0CB-264DF3270CC0
DOI	https://doi.org/10.5281/zenodo.3804750
persistent identifier	https://treatment.plazi.org/id/03C78785-4625-FFE9-4190-443C3036F968
treatment provided by	Valdenar
scientific name	Phialodonta introtuberculata ( Connolly, 1933 )
status	gen. et comb. nov.

Treatment

Phialodonta introtuberculata ( Connolly, 1933) View in CoL gen. et comb. nov.

Figs 14 View Fig , 16 View Fig A–D, 19G–H

Afrodonta introtuberculata Connolly, 1933: 147 , text-fig. 1(9), pl. 7, figs 5–8.

Afrodonta introtuberculata – Connolly 1939: 255, text-fig. 19(9). — Solem 1970: 361. — Herbert & Kilburn 2004: 247, text-fig.

Diagnosis

Shell relatively large, narrowly planorboid, spire slightly sunken; protoconch initially smooth, becoming microscopically shagreened and finally with low axial undulations (diameter ±350 μm); teleoconch sculptured by relatively strong, close-set, compound axial riblets, intervals between riblets with 3–4 microscopic axial threads; spiral sculpture scarcely evident even in umbilicus; parietal and basocolumellar dentition lacking; palatal region with 1–3 axially aligned pairs of denticles set back ⅛ to ½ whorl behind outer lip, outermost pair usually visible through aperture, the others apparent only through translucent shell; lower denticle well below periphery, upper one slightly above periphery; number and position of denticle pairs somewhat variable and related to degree of development; umbilicus shallow and very wide. Shell translucent, honey-brown when fresh; diameter up to 2.0 mm.

Material examined

Holotype

SOUTH AFRICA • KwaZulu-Natal, Nottingham Road; prior to 1928; A.J. Taynton leg.; NHMUK 1931.6.4.1.

Paratypes

SOUTH AFRICA • 3 specimens; same collection data as for holotype; NHMUK 1937.12.30.2759 to 2761 .

Other material

SOUTH AFRICA – KwaZulu-Natal • 4 specimens; Karkloof, Mbona Private Nat. Res., Holbeck ; 29.3009° S, 30.3615° E; 1300 m a.s.l.; 22 Jun. 2002; D.G. Herbert leg.; mistbelt Podocarpus forest, in leaf-litter; NMSA W216 About NMSA GoogleMaps • 1 specimen; Karkloof, Mbona Private Nat. Res., Holbeck area ; 29.30119° S, 30.35899° E; 1400 m a.s.l.; 25 Apr. 2004; D.G. Herbert leg.; mistbelt Podocarpus forest, in leaf-litter; NMSA W1810 About NMSA GoogleMaps • 3 specimens; Karkloof, Mbona Private Nat. Res., Holbeck ; 29.30339° S, 30.36525° E; 1330 m a.s.l.; 24 Oct. 2004; D.G. Herbert leg.; mistbelt Podocarpus forest, in leaf-litter; NMSA W2438 About NMSA GoogleMaps • 1 specimen; Karkloof, Leopard’s Bush ; 29.3183° S, 30.2580° E; ca 1350 m a.s.l.; 23 Nov. 1998; D.G. Herbert, M. Seddon and P. Tattersfield leg.; mistbelt Podocarpus forest, in leaf-litter; NMSA V8417 About NMSA GoogleMaps • 3 specimens; Karkloof Nat. Res. ; 29.30° S, 30.23° E; 1 Dec. 2003; A. Moussalli and D. Stuart- Fox leg.; mistbelt Podocarpus forest, in leaf-litter; NMSA W3789 About NMSA GoogleMaps • 7 specimens; Nottingham Road ; 29.358° S, 29.995° E; ca 1500 m a.s.l.; pre-1928; A.J. Taynton leg.; NMSA A9191 About NMSA GoogleMaps • 46 specimens; same collection data as for preceding; NMSA A9192 About NMSA GoogleMaps • 3 specimens; same collection data as for preceding; NMSA A9193 About NMSA GoogleMaps • 6 specimens; same collection data as for preceding; NMSA A9221 About NMSA GoogleMaps .

Distribution and conservation

A narrow-range endemic ( Fig. 14 View Fig ), known only from the Karkloof–Nottingham Road area in the KwaZulu-Natal Midlands, at 1300–1500 m a.s.l.; in leaf-litter of southern mistbelt forest. Judging by the numbers of specimens in the original samples collected by A.J. Taynton in the Nottingham Road area (pre-1928), the species may be locally common or abundant. There are a number of provincial and private nature reserves in this area in which the species has been collected in recent years.

Remarks

Phialodonta introtuberculata gen. et comb. nov. is distinguished from other species in the genus by its much flatter shell and paired palatal dentition. Afrodonta geminodonta sp. nov. has similar sets of paired palatal denticles, but its spire is raised, the axial sculpture much finer and the umbilicus much narrower.

Specimens somewhat resembling P. introtuberculata gen. et comb. nov. have been found in the Creighton area (Hlabeni Forest, 29.975° S, 29.742° E, NMSA V5219). However, although they have similar palatal dentition, their axial sculpture is noticeably finer, the umbilicus not as wide and they are milky-white in colour.