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
Herbert, David G.
European Journal of Taxonomy
2020
2020-04-17
629
1
55
7PZ8J
Herbert, 2020
Herbert
2020
[557,848,615,642]
Gastropoda
Charopidae
Amatholedonta
Animalia
Stylommatophora
23
24
Mollusca
species
fordycei
gen. et sp. nov.
Figs 8E–H, 9, 18E–F
Diagnosis Shell relatively large, biconcave with deep, tightly coiled whorls; spire distinctly sunken; protoconch smooth, globose; teleoconch sculptured by fine, close-set axial riblets, spiral sculpture virtually obsolete; aperture narrow, crescent-shaped, lacking parietal and columellar dentition; palatal region with 1–2 axially aligned rows of denticles set back 1⁄ 6and 1⁄ 3whorl behind outer lip, visible only by transparency; each row with three denticles, situated at, below, and above periphery; umbilicus of moderate width and deep, V-shaped. Shell translucent, straw-brown; diameter up to 2.0 mm.
Etymology Named after the typelocality, Fort Fordyce, E. Cape.
Material examined Holotype SOUTH AFRICA• E. Cape, Fort Beaufort area, Fort Fordyce Nature Reserve; 32.69556° S, 26.48556° E; 1120 ma.s.l.; 30 Dec. 2008; M. and K. Coleleg.; south facing indigenous forest, under logs; diameter 1.84 mm, height 1.10 mm; NMSA W6668/T4270. Paratypes SOUTH AFRICA– E. Cape• 2 specimens; same collection data as for holotype; NMSA P1020/T4271• 8 specimens; NW of Fort Beaufort, Fort Fordyce Nature Reserve; 32.667° S, 26.483° E; ± 1100 ma.s.l.; 8 Jul. 2001; C. Symesleg.; in forest leaf-litter; NMSA V9343/T4266• 11 specimens; Fort Fordyce Nature Reserve, kloof with sheer krantz; 32.68808° S, 26.51304° E; 6 Oct. 2009; M. Coleleg.; ELM D16076/T168• 20 specimens; Fort Fordyce Nature Reserve, near Harris Hut; 32.68342° S, 26.47670°E; 5 Oct. 2009; M. Coleleg.; ELM D16087/T169.
Description Shell relatively large, diameter up to 2.0 mm, H/D ratio ±0.55, biconcave with deep, tightly coiled whorls; spire distinctly sunken; last adult whorl not descendant; suture strongly indented, and apical and basal portions of whorls strongly convex, peripheral portion evenly rounded. Protoconch comprising globose apical cap plus approx. 1.0 whorl; diameter ±325 μm; smooth. Teleoconch of up to 3.75 whorls; sculptured by fine, close-set axial riblets, with intervals 1.0–1.5 times their width at whorl periphery; spiral sculpture virtually obsolete. Umbilicus of moderate width and deep, V-shaped. Aperture narrow, crescent-shaped, but apical and basal limits rounded; parietal and columellar dentition lacking; palatal region with 1–2 axially aligned rows of denticles set back 1⁄ 6and ⅓ whorl behind outer lip, not visible through aperture and apparent only through translucent shell; each row with three denticles, situated at, below and above periphery, the upper two rounded (uppermost sometimes axially elongate), the lower one an elongate, in-running ridge. Shell translucent, straw-brown.
Distribution and conservation A narrow-range endemic ( Fig. 9), known only from the Fort Fordyce Nature Reserve, near Fort Beaufort, E. Cape, at approx. 1100 ma.s.l.; in leaf-litter of southern mistbelt forest. Fort Fordyce Nature Reserve is a formally protected area managed by Eastern CapeParks and Tourism Agency.
Remarks Amatholedonta fordycei gen. et sp. nov.resembles Am. bimunita gen. et comb. nov.from the neighbouring Hogsback region. It differs from that species in having much finer axial sculpture and a somewhat less deeply sunken spire. In addition, the palatal dentition contains only three denticles per row (instead of 5–6), of which the most basal one is markedly more elongate.
2605305620
south facing indigenous forest, under logs
2008-12-30
NMSA
M. and K. Cole
South Africa
1120
-32.69556
Fort Fordyce Nature Reserve
1
26.48556
Fort Beaufort area
23
24
W6668/T4270
1
Cape
holotype
2605305664
[189,1398,1419,1446]
2008-12-30
NMSA
M. and K. Cole
South Africa
1120
-32.69556
E. Cape
1
26.48556
Fort Beaufort area
23
24
P1020/T4271
2
E. Cape
paratype
2605305612
in forest leaf-litter
2001-07-08
NMSA
C. Symes
South Africa
1100
-32.667
Fort Fordyce Nature Reserve
72
26.483
NW of Fort Beaufort
23
24
V9343/T4266
8
Western Cape
paratype
2605305684
2009-10-06
ELM
M. Cole
South Africa
-32.68808
Fort Fordyce Nature Reserve
1
26.51304
23
24
D16076/T168
11
Western Cape
paratype
2605305737
2009-10-05
ELM
M. Cole
South Africa
-32.68342
near Harris Hut
1
26.4767
Fort Fordyce Nature Reserve
23
24
D16087/T169
20
Western Cape
paratype